Issue #1,130 | Inside the Business of CAD | 23 May 2022
Guest editorial by Dave Edwards
From the Editor
The era of CAD-Is-Amazing is over.
Today’s CAD/MCAD/BIM programs are based on concepts from the 1980s. Change is necessary, as today’s hardware and software capabilities allow for better approaches. CAD is, unfortunately, so integrated into our workflows that change isn’t possible.
Attempts to create new CAD paradigms typically fail, either during development (the aim is too high, the funding too low), or due to lack of interest from the market, which finds itself comfortable with the status quo.
We see snippets of modernity like drawings auto-generated from models, despite the forward-thinkers insisting 2D is dead. The dream of digital twins of horrifically complex projects like skyscrapers is perhaps unattainable.
Let us attend what Dave Edwards has to say to the new crop of BIM vendors described in upFront.eZine #1,128, The Second Wave of BrowserCADs.
For quite a while I’ve been wondering why there aren’t more BIM applications competing in the market. BIM is just 3D graphics combined with the ability to import and export data. Couldn’t any 3D graphics program have data added to its objects, and have the facility to export it out, and call it “BIM”? There may be much more to it than that, and perhaps that’s why some of the other players seem to not be making a dent.
You could add constraints or groupings to any 3D graphics program to form “architectural objects.” Walls could be created from flat planes; they could be moved as one; trimmed, deleted, and all the other functions needed to create floor plans. Door objects could be designed that cut into walls and walls that would heal when doors are moved or deleted. But is it enough?
It has been always interesting to me that Autodesk bought Revit when they already had a long-standing 3D architectural application in AutoCAD Architecture. After years of thinking about it, it occurs to me that the freeform nature of general CAD systems is not well-suited as BIM applications. There is an inherent coordination of objects that BIM applications take into account.
Is the latest crop of new BIM applications going to miss this and just stop too soon?
There are a lot of 3D applications with which you could create 3D models, cut floor plans, create sections, do renderings, and even create fantastic piles of data. Is there something that makes the Big Names different? And why are developers, who are taking old technology and trying to turn them into BIM, not succeeding? Relationships!
Relationships come in several very different fronts. These are not just 3D objects, but ones that will someday, hopefully, be built into breathing buildings. I’ve advocated this before: there must be a coordinated effort for 3D objects, and the materials they’re composed of, to have relationships to real-world parameters.
Is this wall brick? Great! What type of brick? How much does it weigh? How strong is it? What’s its thermal gain? Where to find this information — from the manufacturer? Or should there be a central organization dedicated to providing building material parameters? Just asking!
This is broken-record territory. For this to succeed, there must be open-source file formats for building data exchange. ’Nuf said!
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Why can’t we just slap data on a CAD(D) application and called it “BIM”? Here’s a better question to ask yourself: Why is Revit building a relational database? Unlike just putting lines on a layer and a sheet, building data has many relationships:
Grid lines on levels
Walls on grids lines
Rooms defined by walls
Doors and windows embedded into walls
Components attached to walls
If I move a level, everything on that level moves. If I move a wall, the doors and windows move.
These relationships can cause BIM to be overly complicated and error-prone, but is that the fault of the concept, or the application and/or UX [user experience] developer?
I Hope, I Hope, I Hope
I hope they don’t miss this. To understand most software, you have to understand it at a conceptual and not just a functional level. The young BIM guns may get the sizzle, but will they get the steak? This is really not hard once you understand some of the core designs that must be put into place. I fear if they miss this, they’ll fail. We shall see!
I hope these musings will help users understand the decisions they need to make, and that developers take a hard look before just jumping in.
[Dave Edwards has been a manager, developer, consultant, speaker, and author for almost 40 years in the CAD/BIM industry.]
I’m surprised at such little mention of Rhino in your article. We are fabricators of architectural products and for the last few years, 19 out of 20 projects have been sent to us as Rhino files, and half of the ones that weren’t were originally Rhino and imported into Revit.
Rhino seems to us to have become the default standard for 3D modeling in architecture. - B. K.
The editor replies: The article was specific to new CAD programs that run in Web browsers, introducing them to readers, especially to CAD industry executives who subscribe to upFront.eZine. As you stated, programs like Rhino, Grasshopper, SketchUp, and so on are very popular among architects.
Re: upFront.eZine’s Last Donation Drive
I am of similar vintage, only about three years ahead of you. I know how you feel. I want to thank you for your years of providing a quality newsletter. - Phillip Rutledge
The editor replies: It is interesting how it just happens one day. Same for my neighbour, who used to drive a concrete truck: He woke up one morning and said, ‘I don’t want to do this anymore.’
For those who may have missed it, I wrote in the donation-drive email:
May 1 is the 27th anniversary of upFront.eZine, and at over one thousand issues, it the longest running newsletter in the history of CAD [written by a single editor]. This fall, it comes to a close.
There is a time, I have found among people of my gray-haired age, when you realize, “I just don’t want to do this anymore.” I’ve been semi-retired for a year now, and so decided to end the newsletter on the 37th anniversary of me getting into the CAD writing biz — mid-September, 1985.
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#justdontwanttodothisanymore. Sir! I totally feel what you have just expressed. I too hit this road block many years ago with CAD and stopped draughting, but I have stayed informed and still dabble a bit using trial software and keep up in the BIM space.
Thank you for your years of credible information. - Robert D
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Even though i am no longer directly active in the cad/bim business as you know, i still read eZine with great pleasure. Compliment how you are able to stay up-to-date with new developments, that is hard work. You are very welcome to retire. - Gijs Willem Sloof
Notable Quotable
“It is not your soul which makes you human, but your ability to choose a square containing a traffic light.” - Management Speak @managerspeak
Thank You, Readers
Thank you to readers who donate towards the operation of upFront.eZine:
David Wheeler Short: “Congratulations on your upcoming retirement and a great long run! Thanks!”
Plessey Mathews: “Thank you Ralph for all issues of upFront.eZine that you created and shared, and I enjoyed for these 18 of the 27 years. May your retirement be filled with unexpected newness in all things.”
Robert Shingler: “Just read your latest email and sorry to hear you’re stopping. Good luck in your retirement, I have enjoyed your newsletters and blogs over the years and wish you well for the future.”
Stephen Warrick: “Thanks for ‘How to make Eudora 7 work with Gmail servers’.”
To support upFront.eZine through PayPal.me, then I suggest the following amounts:
Issue #1,122 | Happy Valentine’s Day! | 14 February 2022
Guest editorial by Leo Schlosberg
Glass fiber reinforced concrete (image source Al Blair Construction)
I received a call from a roofer who needed a price on some GFRC [glass fiber reinforced concrete] fascia for an addition to a school. Neither GFRC nor fascia was normally in his scope of roofing work, but he was stuck with it in his bid package. He’s been at this for 40 years and so we chatted.
We went over some of the known industry issues. He said he was glad he did not own the roofing company, because he did not see how he could his price work high enough to cover all the assorted risks. He has been around so long that he could complain about the decline of drawings as the industry moved to CAD.
I had forgotten that people could still complain about that. I had commented on this two decades ago in Ralph Grabowski’s newsletter, when he mentioned my words on the occasion of the newsletter’s 20th anniversary. My post was the most controversial editorial he had in those 20 years. (See https://www.upfrontezine.com/2015/05/857.html.)
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I follow constructech news loosely. I mostly get veiled sales pitches. Forty years ago, when I was a minor pioneer in a different industry (IT – focused on what was then called “office automation” or word processing, integrating text and data, and so on) it became clear that sales efforts focused on the benefits of new technology and glossed over, or omitted, the steep implementation costs. This is still true in tech sales.
The big issue in much of constructech, especially in the segment related to design (CAD, BIM, generative design, and so on), remains knowledge, or rather the lack of it, embedded in designs. The complaint that CAD made drawings worse is based on the observation that the knowledge embedded in the drawings has declined. This is undeniably true.
When I used to work on restoration projects, I would be struck by how the original drawings of century-old structures were so much more detailed and in better correspondence with what was actually built, than modern drawings. The challenges created by all the complex knowledge embedded in the built environment are typically underestimated by those who have not spent a lot of time and effort in the muddy swamp water of the physical realities of materials and structures.
I clearly recall, with fondness, an engineer who was a salesman of admixtures (chemicals) for concrete, sitting me down at lunch one day and patiently explaining to me that “sand” is not one thing, not a simple homogeneous material, but a source of lots of relevant complexity. Everywhere we turn in this business, we run into that sort of complexity.
Software people are not used to complexity, because “data” is an abstraction and computing is full of wonderfully controlled interfaces. By contrast, construction is a collection of physical realities that may not be nicely consistent and homogeneous; that change with changes in moisture and temperature; and are subjected to environmental forces (wind, rain, hail, lightning, earthquakes, soil settlements, and so on). In turn, these complex materials have to interface with other materials. Some of the interfaces are well understood and standardized; others are not, and so become a common point of failure. Data does not have to deal with this sort of thing.
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In conjunction with an extremely seasoned and knowledgeable fabricator, I delved into the school renovation project manual and searched for photos of the existing school to better understand the limited information in the contract documents. Turned out the documents made little sense. There was zero correspondence between the detail (called out as one kind of GFRC, but we thought it should be another type, or maybe even cast stone) with no spec for the GFRC.
Before becoming mostly retired, I dealt with this regularly. Now I am astonished and reminded that industry has made so little progress in the problems of design-bid-build as it exists in the real world.
Leo Schlosberg was the founder of Heavyware.com and is now the retired owner at Cary Concrete Products.
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Siemens released an NX With No Name, calling last week’s update to its flagship MCAD program “latest release” sans version number (although captioning during the launch video seems to label it NX 2007). New functions include
NX topology optimization
Design space exploration
NX voice command assistance
Part orientation optimization
The official launch video can be viewed on YouTube.
I’m a little biased, since I sell Solidworks, but everything “new” you described in Solid Edge has been available in Solidworks for several years. I’m not sure I understand why any company would choose Solid Edge over Solidworks. - Sam Scholes, senior account manager Go Engineer
The editor replies: The reluctance could be due to a number of reasons:
Political — they don't want to buy from Dassault
Top-down — they've been told to buy Solid Edge
Compatibility — the customers they deal with also use Solid Edge
Checkboxes — Solid Edge does things competitors do not
UX — they might prefer the way Solid Edge works
For me, UX is the #1 concern in the software I select, followed by checkboxes.
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Thanks for the article on Solid Edge. I already used (giving you credit) the comment [below] to some of my colleagues about our need to learn our interdepartmental processes better so that we can develop better programs that solve the right problems.”
“Solid Edge benefiting from their use of its CAD in its own engineering projects and how that offers insights into development of functions that are otherwise hard to program and that many of their rivals can only dream of offering someday”
Also, Jeremy has a good eye. Thanks for the Dogbert. Scott Adams is another of my favorite authors! -Ron Powell
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I used to work for one of Siemens’ divisions. The engineers weren’t very happy when word came down from the Mother Ship that they had to start using NX, instead of pre-Wildfire Pro/E and ancient seats of AutoCAD. The story everyone heard was that the NX sales force was tired of hearing the question, “So, what CAD software does Siemens use themselves?”
It’s a good example of how weirdly unscientific the sales world is. That question about the software the parent company uses is exactly the kind of question I like to ask of salesmen, just because it’s fun to back them into a corner and watch them flail. But trust me, what software companies use has absolutely zero impact on my buying decisions.
I’ve been on the receiving end of this stuff, too, and remember having to design an optional set of wide tracks for a piece of machinery, on a salesman’s insistence that the customer said the only reason he was buying Deere, instead of ours. was because their tracks were an inch wider.
The older, wiser salesman tried to explain to me that it was just an offhand comment to get the pesky salesman to go away, and that it didn’t matter what we did, the customer wasn’t buying our machines. (He had a large fleet of exclusively Deere equipment).
We did the wide-track option, tested it, and ordered parts for production. As far as I know, those sets of tracks are still on their pallets, twenty years later, slowly rusting into the ground.
Great write up on Solid Edge. It’s one of those options that doesn’t seem to get much attention. - Jess Davis
The editor replies: I worked at a consulting firm before the transition to CAD. They had a look at Intergraph, but $100,000 per seat was too much. Civil engineering is, after all, not all that complex.
Next, they had AutoCAD demo’ed, but when the salesman suggested that a 10MB hard drive would be needed for AutoCAD to work properly, the added cost was deemed prohibitive, about $2,000 at the time. (Later, I found AutoCAD v1.4 worked just fine with two floppy drives.)
They decided on Anvil CAD as their first CAD system, which, as you might guess, was not the best choice. I have no idea how that came about. Some years later, they bought into AutoCAD, but then found they were now somewhat incompatible with Microstation, which the Ministry of Highways used.
Mr Davis responds: I worked for some years at a trencher manufacturer. When I started, they were using Intergraph on Interact workstations. What a strange world that was! I remember the tech replacing a graphics board that was the size of pizza box. He mentioned it was $12,000 or something like that.
I heard about a gigantic inter-departmental war where the IT priesthood locked horns with engineering, they being natural enemies. When it was finished, engineering triumphed by going with a CAD system that ran on a DEC mainframe instead of the IT department’s beloved IBM mainframe, which is what the rest of the company ran on.
By the time I left five years later, they were on Intergraph Microstation PC [written by Bentley Systems, marketed by Intergraph], and at my next job I instituted CAD with a copy of Microstation on a PC that I got from our in-house buyer, because he didn’t like it, and wanted to go back to his green-screen terminal.
I remember harassing the poor guys demo’ing Pro/E with questions like “So, if we buy your software, can we still run in on hardware from Wal-Mart?”
As an electronics and computer tech for > 40 yrs I’ll explain a few things that people don’t get [about erratic cursor movement caused by poorly-located mouse dongles].
No, it’s not Microsoft’s (or the mouse manufacturers’) fault with driver updates. The problem isn’t software, it’s hardware. These devices are radios. Unfortunately (or not, lol) we can’t “see” radio waves. So we can’t see what’s happening, but there are so many devices transmitting in the frequency range used by mice that there can be countless combinations as every environment varies. This is totally a radio interference problem.
It’s not the receiver’s fault, nor faulty design. The need for such small receivers (nano) came from our need for small portable setups (laptops). People hated the large receivers we used to have, they often hit them and broke them. Since the nano receiver is so small, it has a tiny antenna. Larger antenna are less likely to pick up interference. People wanted small. They gave it to us.
Current Logitech Unifying receiver (top), older one (above)
USB plugs are usually grouped. They’re always placed in clumps. That means the device plugged in next to it can interfere, as it’s right beside the mouse receiver. I’ll give you a real example: my Logitech MX mouse’s nano Unifying receiver is plugged directly in the front USB port of my large tower. Worked great. But when I plugged a USB DVD player into the next port, it went nuts! As it’s not unusual to have four or six ports next to each other, your odds aren’t good.
The standard technician’s response to naughty mice has always been “change the port.” While this works, most techs don’t understand why, as they’re computer people, not electronics people. It’s radio interference.
“But it worked for years like this!!” Your environment changed. You got a new printer that’s plugged in next to it. You got a new cellphone or cordless phone, etc, etc, etc. You can’t see radio waves. Something changed, not the mouse.
The batteries are low. A strong signal can cut through the interference, but as the batteries get weaker (or in the case of built-in rechargeables, they’re aging and aren’t as strong), that lowers the power and raises the interference effect. Your mouse isn’t shouting loud enough to be heard.
It’s money! Yep, the good ole $$$. Not the receiver’s fault. The USB plugs next to or near it are not shielded. Virtually all wires nowadays are fully shielded or our electronic world would grind to a halt with interference problems between devices. Unshielded wires act as long antennas and everything would be interfering with every other thing that had a cord. However, it’s expensive and difficult to shield the plug, and the bean counters object to a pair of $0.50 plugs on a $1 wire, so the engineers are overruled and they ahve to use a $0.10 plug that’s not shielded. Guess what’s right next to your nano receiver? Yep, that unshielded plug.
So there you go. It’s spelled “i n t e r f e r e n c e!” This is the solution: moving the receiver away from the interference allows it to be heard. Awesome fix, Ralph! - RM (on WorldCAD Access)
Notable Quotable
“Let’s face it, Facebook and Twitter are charities that allow you to donate free data to needy billionaires. Say what you want about Bezos and Musk, they actually produce something other than mental illness.” - Iowa Hawk
Thank You, Readers
Thank you to readers who donate towards the operation of upFront.eZine. To support upFront.eZine through PayPal.me, then I suggest the following amounts:
Issue #1,120 | Inside the Business of CAD | 31 January 2022
Guest editorial by Ivan Rykov
Plug-in adding a toolbar and a panel to Rhino
Many projects developed by LEDAS are plug-ins for CAD software programs, ranging from powerful systems like CATIA, to lighter weight solutions like Rhino. Oftimes, we help our customers decide on the direction in which their ideas are best developed: in the form of a plug-in or as a standalone program.
Pros and Cons of Plug-ins
Plug-ins either solve specific problems, or else add functions missing from CAD systems. A good example is CAMWorks from HCL, an advanced plug-in that adds computer-aided manufacturing functions to the Solidworks MCAD system.
Comparing plug-ins with independent applications, we found that plug-ins are better suited to software used in-house by design engineers, with the aim of assisting their day-to-day work. In certain cases, the plug-in approach significantly reduces the cost of development. Ready-made CAD systems work with plug-ins through their APIs [application programming interface].
The drawback to plug-ins that you have to run them on a host application. Before the plug-in can be used, you have to pay a license fee and then install the host software. Plug-ins intended for wider distribution have their demand limited by the number of seats found of the target CAD system.
The APIs provided by CAD systems are often thought of as a way to extend and tailor functions of the CAD system itself, rather than for creating customized processes to solve particular problems. Also, it’s not always an easy task to make a focused plug-in which overrides the user interface of the host application to substitute its own workflow.
We have found that, in general, end-user plug-ins are not usually at the top of our customers’ wish lists.
Pros and Cons of Standalone Applications
More commonly, our customers want software made as standalone programs for the desktop and, more often in recent years, a client-server Web application.
When considering the development of an independent application, either for desktop or the Web, keep in mind that it will require a geometric kernel with which it constructs, represents, and tessellates 3D objects. (We talk more about kernels on our 3D Modeling page.) The annual cost of a subscription license for a kernel is usually significantly higher than a one-time payment for a single license of a lightweight or middle-class CAD system on which plug-ins can run.
Another source of cost is the effort to implement 3D scenes: visualization, camera manipulation (zoom, pan, rotate), object manipulation (selection, movements), and so on. With a plug-in, the host application provides all these features via its API. In case of standalone applications, these have to be programmed at a low level, or else with the help of licensed visualization components.
Types of Plug-in Solutions
From our experience, Rhino is an excellent example of a customizable system. It allows us to hide most of its default panels and toolbars, and then we can easily create our own panels using WPF [Windows Presentation Foundation]. This gives us almost the level of same control over the Rhino’s user interface as do independent WPF applications. (See figure at the top of this article.)
In other CAD systems, this could become problematic as they might use outdated GUI frameworks (do you recall WxWidgets?) or are limited to UI controls predefined by their APIs.
If, however, the application has an external API that can be called from another process, such as through COM or WCF, then we can build a plug-in UI as an external application that interacts with the host CAD system through the API. (Technically, this is then not strictly considered a plug-in.)
This allows us to build the UI using modern technologies exactly matching the required processes, yet still using the geometric kernel and 3D scene capabilities of the host CAD application. This approach is quite popular with our customers, although a somewhat more complicated approach.
How to Decide
So, we have trade-offs that can be resolved by knowing the number of simultaneous software users:
When the cost of copies of the host CAD system does not exceed the cost of a custom application (with licenses for geometric kernel, visualization components, and 3D scene implementation), a plug-in is the cheaper option.
It’s worth noting that the cost of licensing the host application can at times be considered to be zero when company engineers are already using the software in their daily work. In this case, a plug-in based on such a system possesses the additional benefit of fitting a familiar environment.
Thus, in our experience, plug-in solutions are quite popular for semi-automation of certain CAD-related processes performed by a small group of engineers, or else by a large group already using a suitable CAD system. Many of our digital medicine projects, for example, are in the form of plug-ins.
[Ivan Rykov is chief technology officer at LEDAS since 2004. Dr Rykov graduated from the mechanics and mathematics department of Novosibirsk State University, and in 2009 received his PhD in physics and mathematics specializing in discrete mathematics and mathematical cybernetics. More at ledas.com/en.]
Project Newplex 2.0 is the advanced SHX font designed for technical documents; compatible with every DWG-based CAD program that supports Unicode SHX files.
Features
Advanced character forms for readability & clarity
Autodesk launches Flex, its token-based pay-as-you-go system for renting software by the day. AutoCAD, for instance, costs 7 tokens (US$21) for 24 hours, which can be paused by closing the application. Netfab Ultimate, at 55 tokens daily, is the most expensive.
For the very intermittent user, like me, this would be a useful duration, but, alas, I cannot buy a day’s worth, because the minimum purchase is 500 tokens that last just one year, and costs just C$365 less than an annual subscription. Maybe that’s the point. Autodesk warns that “daily rates are subject to change,” meaning the cost/token could rise at any time. autodesk.com/benefits/flex/estimator-tool
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OpenDesign Alliance initiates development of a scan-to-BIM software development kit. Or more accurately: laser scans > polygonal surfaces > AEC objects (b-reps) > parametric parts classified in IFC, Revit, and other formats.
To join the dozen other firms working on it, you first have to become a SIG member at $20,000/year; details at https://opendesign.com/scan-to-bim.
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Here are some of the posts that appeared recently on my WorldCAD Access blog:
While experiencing the same problem with my Logitech M185 and reading through suggestions [on WorldCAD Access], I took a hint from a very old post that referenced the jumpy problem on an old mouse with a rubber ball. It suggested cleaning the ball and inside the mouse.
My newer M185 did not have a ball, but rather a movement sensor window. I took a Q-tip and cleaned the little window on the underside of the mouse, [see figure above] and the problem disappeared. - Roger Carlsen (via WorldCAD Access)
Re: Which Comes First: Models or Drawings?
The usefulness of either a model or a drawing depends, in part, on what you are using it for. If you are a developer, a rough hand sketch might do fine. If you are an estimator you may be able to get by with fewer details (and less accuracy, whatever that means) than if you are trying to build a building.
Two issues run throughout a real-life examination of models and drawings:
1. Knowledge. Does the creator have the knowledge necessary to create the desired level of detail? In construction it is ridiculously impossible for an architect to have the requisite knowledge for the final design of every component in a building. The less knowledge implicitly contained in a drawing or model, the less useful it is. Each type of use requires a different amount of knowledge to implicitly dwell within the model.
2. Responsibility. Who is legally required to get it right? In USA, architects, who most typically create a model, have a low bar for liability for the design; that is pushed contractually to general contractors and from there to subcontractors.
Subs cannot stay viable in the business without serious knowledge; the others can shrug off any liability for not getting a design quite right. - Leo Schlosberg
The editor replies: Back in the day when I designed traffic signal installations, we used symbols like the ones shown below, which contractors interpreted.
“The experts predicted the future, but nature had other ideas.” - Richard Fernandez (@wretchardthecat)
Thank You, Readers
Thank you to readers who donate towards the operation of upFront.eZine. To support upFront.eZine through PayPal.me, then I suggest the following amounts:
There is a way to determine people’s ability to structure designs. Ask them to arrange virtual furniture in a room:
When they draw rectangles and they annotate them with words like “wardrobe,” “bed,” and “table,” then place dimensions and distances, you are looking at a designer. The designer is a planner solving the “What can and should be done” problem.
When they create perspective views with details like armrests and cushions, it seems that they are “constructors” who would be better trying their hand at mechanical engineering. (See figure below.) Constructors solve the “How to make” problem using original, non-standard solutions. This is welcome in mechanical engineering, which has a pre-production testing stage, which does not exist in the design of buildings where non-standard solutions are risky.
Perspective drawing made by a constructor
“What is a model for, if you already have drawings?” This is the question I am asked during discussions on automatically generating 3D models from 2D drawings. People have no idea that it’s possible to make drawings without first constructing 3D models. For instance, this is the weighty opinion of a developer of one 3D modeling program: “The model is the only source of information for drawings. Drawings are nothing more than views of the model.”
And what do standards and textbooks say? When we consult them, we read terms like “projections,” “sections,” and “cross-sections,” such as illustrated by the figure below.
Orthogonal and other projections of a 3D model
When we read further, we learn that a floor plan is a horizontal section at the level of the window openings, or 1/3 of the story’s height. We might think that this confirms the priority of models over drawings. An example from a real project, however, casts doubt on this conclusion.
Depicted in the figure below is a shop. This is practical, clear, but how can it be called a “horizontal section” when it shows a variety of elevations? Some are at -2.500; there is a rail track at floor level; some platforms at +1.000 and +4.000; many columns and vertical bracings (above the floor, and below the crane rails); walls at level of windows; bridge cranes and a crane landing platform (just under the roof).
Production building plan at a variety of elevations
This exactly is a plan, a schematic representation of what should be built. It is an extremely simplified representation, with all plan objects refined and detailed elsewhere. By the way, sections are the same as plans, except that they describe builds from different aspects.
PROJECT NEWPLEX v2.0
Project Newplex 2.0 is the advanced SHX font designed for technical documents; compatible with every DWG-based CAD program that supports Unicode SHX files.
Features
Advanced character forms for readability & clarity
The synthesis of spatial objects from their projections is called “the inverse problem of descriptive geometry,” and is an unsolved technical problem. Nevertheless, for hundreds of years, designers and builders have been synthesizing mental versions of 3D building models from 2D drawings. Then, builders transform the mental objects into real ones — how do they do it?
It is impossible to build models using projections, but it is possible using conditional images that have parameters tied to them. When we draw a circle (even if it is not perfect), and then write just two words, such as “Sphere d1800,” we create the parametric description of a sphere as a spatial object.
A parametric description consists entirely of conventional signs, and as a result is a linguistic description. Parametric modeling is essentially linguistic modeling. As a rule, parametric descriptions include the following elements:
Object type designations, formatted as text (e.g., “sphere”)
Conditional graphical representations of objects (e.g., drawing of a circle)
Parametric designations as text (e.g., “d1800”)
Conditional auxiliary images (e.g., dimensions and extension lines)
There are cases where the object type designator is not explicitly presented. In such cases, it can be reconstructed from the drawing context. For instance, the context may be provided by the drawing’s name, such as “column layout scheme.”
Any parametric description assumes the existence of an associated execution procedure, such as a mathematical formula, a computer program, or a detailing algorithm linked to detail drawings. From a programming point of view, a parametric description is a function call with parameters passing to it. When executed, the function transforms conventional signs and images into mental or digital models.
We can come to the conclusion that the primary method for analyzing drawings is to establish parametric descriptions for each building element. In drawings, the same building elements are usually described in several different contexts, such as being present in different views, on different drawings, in different drawing sets, and so on.
As an example, let’s try to restore the parametric description of the column located at A-17 in the figure below. The type of object (column) is easily determined from the context: column sections in this drawing are rectangles. There is, however, no other information tied to the object.
Identifying parameters of column A-17 from the equivalent column A-4
So we apply this well-known rule:
If, in a group of objects that are identical in appearance and purpose, there is only one object provided with parameters (dimensions, marking, designations), then all other objects in the group inherit these parameters.
In the group of columns along the A-axis, we see column A-7 is associated with detail #4. (See figure below.) If we were to refer to detail 4, we would see a refined column section with its dimensions, and snaps of the section to the co-ordination axes on the plan.
Detail 4 describing column A-7 and referencing Section 1-1
Using the details of section 1-1, we can determine the column’s top and bottom elevations. We apply the parametric description we obtained from A-7 to all columns (except for the corner ones) of row A, including the column at A-17.
Step-by-step Detailing of Objects
So. We managed to determine the definition of a simplified architectural column. A short parametric description cannot completely define complex structures, as real columns are. Nevermind: during the early stages of planning, our knowledge of objects is very approximate and vague.
During the planning process, structural drawings appear following the architectural ones, from which the columns obtain designations (that will be marked). A separate drawing of an abstract column representative of the columns of this type will appear. The structural elements of this abstract column — the formwork, rebars, embedded items — will, in turn, be detailed.
The essence of step-by-step detailing can be described this way:
Any project detail is itself a project
Any project is itself a project detail
During step-by-step detailing, a hierarchical structure is built by which the types and parameters of the upper-level objects are the context for lower-level objects.
Knowledge and Data
Parametric descriptions and their associated execution procedures are knowledge of what and how the work should be done. As a result of the execution of the parametric description, we get an object’s 3D model, which is the object’s database. Let’s take a closer look at the process.
In the figure below, there is a drawing fragment explaining the principle of reinforcing the floor slab.
Drawing of slab reinforcement as a representation of knowledge
The recipient of the drawing extracts a parametric description from it, applies the execution procedure, and, as a result, gets a mental model of the slab reinforcement. When the recipient is a builder, he will transform his mental model into real reinforcement in the field.
The process of creating a model in a 3D modeling program is, in principle, no different from a traditional drawing. By some means or other, the reinforcement contour is defined; the diameter, steel class, spacing, and possible overlap of rebars are specified.
The end result is, however, different. The execution procedure creates a computer model of a set of rebars with attributes attached to every bar. This model is saved. The figure below represents a top view of the reinforced slab as displayed by a computer model.
Top view of the reinforced slab model as a form of data representation
As mental models are built solely on the basis of visual perception, let's compare the two figures:
Drawing — shows a single abstract bar, with information attached. The bar defines the size, location, and attributes of all other bars in the planned reinforcement slab. We do not see individual bars, but we get a very good idea of the slab reinforcement.
Model — shows lots of bars. Annotations need to be added to all bars, and many dimensions need to be placed. When the slab is large and contains a lot of rebar, we get a messy, poorly readable picture. The result is a poor-quality mental model and, accordingly, a poor understanding.
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Collaboration begins with understanding. Like it or not, we have to do what BIM calls "automatic" extraction of drawings from models.
A comparison begs. We cook borscht according to a recipe, throw away the recipe, and then, using complex algorithms, try to extract the recipe (the drawings) from the finished borscht (the models). This is the wrong way around of doing things.
The parametric drawing style is based on the assumption that recipients of the drawings have a professional set of algorithms for drawing analyses and for building mental models based on the analyses’ results.
In practice, this means that drawings should be made so that for each structural element, its parametric description can be restored. The mental object is modeled by calling the appropriate execution procedure associated with the parametric description.
Parametrics Determine Drawing Precision
In many cases, deviations from the image’s scale and accuracy contribute to the readability of drawings and the ease with which they can be adjusted. Consistent adherence to accuracy prevents this, surprisingly enough. The use of parametrics makes the meticulous precision of graphic images meaningless, and so it makes no sense to measure things on drawings. Indeed, the Russian standard prohibits such measurements.
The geometric accuracy of parametric drawings is determined by the accuracy of the values of dimensional parameters. In most cases, editing is limited to adjusting parameters, without affecting the graphic images. (It should be noted that parametric drawings are difficult to read when the proportions of objects are grossly distorted.)
As we see, this contradicts the autocad-style of drawing with its associative dimensions. The autocad style is based on drawing graphic images with tools that ensure great accuracy; the primary method for adjusting drawings is by editing the graphic images as required.
Machine Interpretation of Drawings
When professional algorithms are transferred to a computer, we get the ability to carry out automatic drawing analyses and building a computer model based on the results of the analyses.
A set of drawings can be considered a program written in a professional language — the equivalent of a high-level programming language. The program is compiled as a whole; a machine interpreter of drawings is in fact a compiler. As a result of the compilation, an overall execution procedure is formed, such as an IFC text file. In the end, a computer model is created. Note that the primary method of programming drawings is the step-by-step detailing of objects, better known as top-down design.
How is this different from the traditional way of creating models with 3D modeling software? All of them use a command interpreter as the input interface for 3D modeling. Complex objects are created by assembling pre-prepared components, whether primitives or parts. This technique implements the bottom-up principle; it simulates the construction process and so has nothing to do with planning.
It is clear that for many, assembling a building from cubes is easier and clearer than creating a linguistic description of a building with help of drawings. Unfortunately, except for the model in the computer’s memory, what’s actually needed are models in our heads. A set of drawings is an algorithm of understanding. It is impossible to replace the reading of this algorithm with something else, such as wandering across a computer model.
Crucially, the delineation of legal responsibility within the framework of this algorithm is also not a problem.
Machine Interpretation of Sketches
The parametric style of drawing allowed engineers with blunt pencils on broken-down Kuhlmann drafting machines to create absolutely accurate (not in the autocad sense) drawings. The independence instrumental to parametrics creates the principled opportunity of interpreting freehand sketches and drawings.
The figure below illustrates an example of such an interpretation. The problem is to turn a freehand line (possibly the sketch of a beam) into an accurate two-dimensional model.
Steps in interpreting the freehand line as a beam
Here are the steps involved:
Step 1. Bridge the gap, created by careless sketching. The extent of the gap is insignificant and is not numerically specified.
Step 2. Straighten the curve. The bend radii and the curve deviations from the straight line passing through the curve endpoints are insignificant and not numerically indicated. From this, we deduce that the curve is a straight line segment.
Step 3. Refine the x coordinates of the line’s endpoints. Horizontal deviations of the line’s endpoints from the A-axis and the 6000-dimension extension line are insignificant and so are not numerically specified. The x-coordinate at the line’s left endpoint is equal to xA (xA is the x-coordinate of axis "A"); the x-coordinate of the right endpoint is xA + 6000.
Step 4. Refine the z coordinates of the line’s endpoints. Vertical deviations of the line’s endpoints from the 3.000 elevation’s extension line are insignificant and not numerically specified, as is the inclination angle of the line. The z coordinates of the line’s endpoints are the same, and both are equal to 3000.
We completely restored the parametric description of the object.
Standards for Preparing Drawings
Current rulemaking in the area of preparing drawings stopped trying to combine the Gaspard Monge legacy with the drafting practice of the 1980s. [Mr Monge invented descriptive geometry, which became the basis for technical drawings.] In my opinion, construction drawings in Russia reached their peak in the eighties. From this, progress regressed, as drawings were made with 3D models and autocad styles of drawing.
Arrested development results in degradation, as shown by the figure below comparing Russian state standards from 1980 (top) and 2018 (below).
Drawing styles from 1980 (top) and 2018 (above)
The Grammar of Drawings
Due to the appearance of 3D modeling programs, a question has arisen about teaching descriptive geometry in technical colleges: Is it still relevant? The crisis in descriptive geometry is a consequence of the same misconceptions about drawings as in engineering practice.
Back in the 19th century, drawings were called “the language of technique,” and descriptive geometry was the grammar of this language. In my opinion, the reasons for misunderstanding were these:
Incomplete awareness that drawings have all the properties of the language in a direct, literal sense
The consequences of not fully thinking this through. For instance, if we speak of drawings as text, then it is not clear what accurate projections have to do with the text
Descriptive geometry can and should develop in the direction of machine analysis of drawings: from classical descriptive geometry to parametric (linguistic) descriptive geometry, a kind of analytic geometry.
[Alexander Yampolsky has designed residential, public and industrial buildings, mainly as a structural analyst. He was an early participant (1982) in BIM at the Minuralsibstroy construction ministry of the Russian government, and developed technology for machine interpretation of drawings. Mr Yampolsky is a graduate of Tula State University.]
Notable Quotable
“The CDC said we can leave the Christmas lights up til January.” - Aubrey Strobel
I keep mourning the passing of CAD as a topic interesting enough to keep producing interesting articles about it. It used to be that you didn’t have to look far to find a great technical topic, or a new way to apply CAD tools. On the Solidworks (desktop — do I really have to specify what the name implies?) side of things, for instance, development has been largely uninteresting.
Developments in design technology seem currently focused on 3D printing: improvements in materials, methods, support structures, finer structures, finishes, and machines to go bigger and smaller. The surge in robotics is related to the hardware side of 3D printing, and also is going gangbusters.
Let’s take a look at what general 3D CAD development has achieved in the last decade or so, and then look forward to what we can hope for in the next decade. The big topics CAD developers have tackled include these ones:
Universal file management
Some CAD systems added file management, but others made it less accessible
Is it possible that Solidworks killed off PDM [product data management] as certain individuals were going out the door to create a new venture with built-in data management?
Alternatives to History-based Modeling
T-splines and related technology
Direct/synchronous modeling
Convergent CAD that combines sub-division meshes + NURBS in the same model
i. Sub-d push-pull ii. 3D scan data iii. FEA meshing iv. 3D print meshes v. Generative techniques for shape optimization vi. Medical, dental meshes
Application Delivery and Data Storage Options
First, decentralizing CAD from mainframes to personal computers
Then, centralizing CAD back to cloud servers
4. CAD in a database
Much data these days is kept in a database format; it makes sense, as it provides built-in data management and turns the idea of file management on its head
5. Various 3D Print Integrations (although most 3D printing advances have been in materials and robotics)
Support structures
Moving specialized functions from specialized software into CAD
Not all of these have been ubiquitous, and not all have impacted all CAD users, but most CAD users have access to these solutions when they need them.
Mechanical CAD with 3D scan-and-print has been a great success in specialty areas like medical and dental. If recent wars have an upside, it in the development of next-generation prosthetics, some strictly mechanical, some with newly developed neural interfaces. Scanning and printing have allowed us to customize attachments to individual injuries, quickly replacing and repairing limbs, and even joints.
Big Ticket Disappointments
When it comes strictly to mechanical CAD, I think we’re in a lull period right now. With all these other interesting things to do, the base technology has been forgotten for a while.
At the same time, some of the big ticket items that CAD developers put on the table haven’t really caught on.
Cloud. I think there was an assumption that cloud computing was going to be embraced in the same way that PC CAD was embraced in the 1990s. But it hasn’t. Clearly, it works for some people, but not for everyone.
This tech will catch on eventually, but too many intransigent engineers have too much invested in overly-complex history-based systems, and so haven’t taken the time to understand the real advantages of synchronous modeling.
Where Do We Go Next?
I’ve made predictions about the future of CAD before. I thought engineer-to-order was the next big thing, as would be synchronous modeling. They weren’t. I predicted CAD-in-the-cloud was not going to be the next big thing; so far, this is my closest to a good guess.
And when is A.I. going to show up, or do we not have the piles of unsorted data required to make A.I. successful?
I really hope the idea of converging different types of data keeps developing, as well as mesh manipulation tools for mechanical CAD. There are so many sub-d tools out there that every big CAD developer should buy one just to understand the data type, the tools involved, their usage, and applications of this kind of modeling. We don’t have to re-develop all of this knowledge.
Another thing I hope gets some play are more specialized tools. We already have tools specific to designing sheet metal parts, frames, piping, and in medical fields. I think more needs to be done with plastic, assemblies, resilience, and local design.
Plastics Design. Plastic parts are so hard to design. The outsides are all minute, custom-made details; the insides, that you don’t even see, can be even more difficult to design. We need a series of functional features that can be applied to models. Maybe this requires a special file format just for plastic parts, as with the other specialized techniques.
Plastic designing and manufacturing need to come closer together. The design of the outside shape and mechanical details, and the manufacturing expertise to make individual plastic parts need to be centralized so that a single person can make the decisions about design and manufacturing. Throwing designs over the Great Wall is not going to be a viable solution going forward.
Assembly Design. And we have to do something about assembly design. Right now, it’s a custom approach every time. We need a tool that follows a process for assemblies, and can reuse information on how assemblies go together. Is it rules based? A.I.? Can it somehow learn about different types of joints, closures, and mechanisms?
We need tools that know how to work with horizontal modeling, resilience, top down, layouts, master models — all these are methods that design software should be able to replicate, and even guide you through. We’re at a point where forcing dumb tools to do smart things is just inadequate. Best Practice rules already exist to help people use tools in poorly structured workflows.
Sustainable Design. Beyond software, I’d like to see product development aim to be more durable and reusable, to get away from single-use products, especially in plastics and packaging. As engineers and designers (and, yes, even marketers), we need to have a conscience. Reject bad ideas.
Throw-away products have always been a bad idea, but someone other than the people for whom this is a religious cause needs to stand up and say so. We need to design stuff that endures, and when it doesn’t endure, it needs to be fixable, and when it can’t be fixed, it need to be recyclable. Not that long ago and certainly in my lifetime, we used to have less stuff, but the stuff we had was more valuable. It lasted longer, because it was built and designed with use in mind, rather than crass consumption.
Local Design. Maybe all of this heads back to more employee-owned companies. I don’t think driving the economy with a bunch of disinterested investors is good for anyone, and obviously centrally-managed economies have shown they don’t work. Globalism is a failure.
Certainly we need to learn to do things locally again. The bigger an organization gets (including government), the more corrupt it becomes, the more disconnected it is from the people who make it work, and should be benefiting from it. Stop sending product development and manufacturing to China. Manufacture molds locally again, make microelectronic chips locally again.
These are things I’d like to see in the next decade.
[Matt Lombard has been working with CAD and as an independent product development professional for 30 years. He is the author of eight books on Solidworks and Synchronous Technology. He blogs at dezignstuff.com/about.]
XVL from Lattice Technologies (part owned by Toyota) is an inbetween format that reads files from most 3D CAD programs, then displays them in an XVL viewer, and used for training and parts lists.
XVL can be exported to 3D PDF, Excel, iPads, and so on. As of 2021, it is native on 3Dexperience; back in 2005, Dassault based its 3DXML on Lattice’s XVL. lattice3d.com/company/xvl-technology
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ARES Commander 2022 from Graebert is now in beta, with an emphasis on the 2D processing of Revit and other BIM models, as well as new features for the Touch tablet and Kudo Web versions of the CAD software.
Desktop beta is downloadable initially for Windows and then later in January for MacOS. graebert.com
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Here is one of the posts that appeared recently on my WorldCAD Access blog:
A.I. projects that attempt to replace humans will fail. A.I. projects that attempt to augment humans have a much more likely path to success. - Randall S. Newton (@RSN_Global on Twitter)
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I recently spent a week working with my colleagues at RIB Software improving the UX and UI in our iTWO software, trying to get a commitment between functionality and usability.
I recall Xerox Parc’s Larry Tesler with his “NO MODES” license plate. I prefer one that reads “NO OPTIONS”, as every option in software is a question to which we programmers have no answer. So we transfer the problem to the user.
I have a new car, the most modern German car, chosen on purpose for being the most digitalized model in its size. It is much more similar to my PC than to my previous car.
You must learn how to use it, as it has lots of options for adapting the car to your convenience. Otherwise, don’t buy this car! Do you really need an acoustic signal when you close the doors? Will you remember that there is a setting for entering car washes? What happens when you forget?
And, of course, it has many “MODES,” which affect my driving. After a day of driving it, I asked the salesman how to stop the car from obeying speed limits, as many of them are nonsense. His solution was completely wrong: he unchecked the “Adapt to road conditions” option; he should have turned on “Ignore speed limits,” which is found in a different menu.
The “Adapt to road conditions” option adapts the car’s speed not only to road conditions, but also to your speed setting and to the car in front. (The car knows the road conditions because it has a GPS; when I tell the car my destination, it reduces speeds in curves, and so on.) Should you think this option is turned on, but it is not, you could easily drive off the road.
Thank you for your insight, your knowledge, and your information. - Fernando Valderrama RIB Spain
The editor replies: I buy old used cars to avoid the electronics shoveled into new ones, which I experienced when renting cars.
The worst was a Ford Edge, where even the heating and cooling required adjustment through a touch tablet, several menu levels deep -- followed by precise 0.5-degree temperature changes that required repeated taps while keeping an eye on the road.
Subsequently, Ford admitted they had gone too far in the digitalization of the car’s UI.
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Thanks for your excellent updates, professional dialogues, and information. Even for us non-mechanical guys, it’s valuable. - Michael David Rubin
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Regarding knowledge: I am a huge fan of Thomas Kuhn's Structure of Scientific Revolutions, from which we got the term “paradigm shift.”
Regarding interfaces: visiting one of my sons I encountered a fancy toaster with a novel (to me) interface. Push the Toast button and the bread is transported down. As I have aged, I have encountered many puzzling interfaces that were once familiar. Ten-15 years ago I could not open the car window to pay the toll. -Leo Schlosberg
The editor replies: I bought a T-fal toaster, because its designers were featured speakers at a CAD conference. They had slanted the top by 45 degrees, so that we could look into it and see how the toast was coming along. (Turns out I never do that.)
Well, you know the special property of 45 degrees: when the toast is released at 45-degrees, it is launched into the air in an arc to land, most times, on the kitchen floor. Not all design improvements are improvements.
Mr Schlosberg responds: Speaking, as we were, of toasters, a cartoon showed up.
Notable Quotable
“Thankfully, there are still hardware Morlocks* to clean up after the mess the Eloi have made.” - Andrew Orlowski
*) The Time Machine, HG Wells
Thank You, Readers
Thank you to readers who donate towards the operation of upFront.eZine. To support upFront.eZine through PayPal.me, then I suggest the following amounts:
Issue #1,112 | Inside the Business of CAD | 8 November 2021
Guest Editorial by John Callen
In the upFront.eZinearticle on Solid Edge 2022, Dan Staples makes the following comment: “I do think [convergent modeling] is a final frontier here, because meshes for a long time were the domain of the film industry and character modeling.”
It turns out that faceted models were the very first b-rep [boundary representation] structures, referenced in 1977 by CMU’s GLIDE, a polygonal modeler.
The Start of It All
GLIDE stands for “graphical language for interactive design” and was a research program in the architecture department at Carnegie Mellon University. The GLIDE program was funded by the Army Corps of Engineers who wanted a system to model their various facilities.
It was headed up by Chuck Eastman, who is generally acknowledged as the father of BIM [building information modeling]. Kevin Weiler, who originated non-manifold topology b-reps as his PhD thesis at Rensselaer Polytechnic Institute, was one of the members of Eastman’s GLIDE team. I was a member of the GLIDE team 1979-1981, where I was responsible for implementing the Euler operations from the original BDS [Building Design System], which were written in BLISS, to GLIDE’s Pascal.
Defining polyhedrons with GLIDE
GLIDE was an extension to the higher-level programming language, Pascal. Solid modeling operations were incorporated into an interpretive version of the programming language. Procedural constructors were developed to model aspects of buildings.
GLIDE pre-dated non-polygonal surface representations. Booleans were performed with the faceted representation; the intersection code was relatively straight forward. Later on, b-rep modelers introduced non-polygonal surface types.
GLIDE subtracting polyhedrons (left) to arrive at a new shape (right).
Romulus. Being developed in parallel to GLIDE was Ian Braid’s BUILD project at Cambridge University in the UK, another b-rep program. The BUILD research was commercially spun off into Shape Data, which was the precursor to ACIS and Parasolid.
Romulus introduced analytics and had discrete intersection routines to do surface/surface intersection calculations based on surface type.
Only later were NURBS surfaces introduced and there was a big debate over whether analytics should be converted to NURBS equivalents and all intersections done in NURBS — or whether to continue to maintain the discrete surface types for precision and efficiency.
Performance and Interactivity
Kepler. After graduating from CMU, I joined the Kepler project at Evans & Sutherland. Kepler was an application development environment front-end to Romulus that provided a design space, giving designers a degree of interactivity not possible with solid modelers at the time. (Kepler really wasn’t an acronym; the project lead chose the name due to the historical individual’s role in astronomy.) Objects were built in the Kepler environment, and then the corresponding modeling commands were passed to Romulus to instantiate the design, often taking many minutes to calculate on a DEC VAX 780 mini-computer.
When the Kepler project’s proof-of-concept was completed, it was decided to no longer pursue the approach.
D-Cubed. Shape Data Ltd was the company that originated Romulus and later Parasolid. John Owen at Shape Data developed his dimensional constraint technology, which is the basis of D-Cubed . It can trace its roots to the earlier D/T-D [dimension/tolerance-draughting] work in Romulus.
After Kepler, I ended up relocating to Shape Data and led a project to implement encoding dimensions and tolerances in Romulus and automatically generating engineering drawings, easily a decade or more before PMI. The D/T-D function was released with Romulus v5.2.
During a design review I had with Bob Sproull, Bob pointed out that the D/T-D framework we had implemented in Romulus could be extended to be a parametric modeling system.
The company, unfortunately, had some very strong positions on how a solid modeler ought to be used and, as a result, did not realize advances like parametric modeling and PMI when they presented themselves. The D/T-D function was later removed from Romulus.
Evans & Sutherland was a distributor of Romulus, and then later acquired Shape Data. This was just the first of a long series of acquisitions passing Shape Data from one company to another, ultimately ending up at Siemens.
ACIS. The managing directors of Shape Data split off to form Three-Space Ltd, the company that created ACIS.
The Continual Development of Representations
Gradually, b-rep modelers expanded their geometry classes to support analytics (cylinders, spheres, toroids, and so on), and eventually a variety of surface representations, such as NURBS.
Facets became the primary method of representing scenes in image generation, such as for flight simulators, where the image generation pipeline was built on facets for performance. This need for image generation performance then moved over to the film industry and character modeling. Highly detailed visuals required many, many facets, though. Eventually facets were replaced by texture maps with which image generation reached new levels of realism.
Non-manifold topology (NMT) b-reps introduced the next level of representation, which allowed for interim Boolean results to exist (but not necessarily persist). ComputerVision’s Liberator project of the early 1990s, headed up by Gary Crocker, implemented NMT and supported mixed model representations — wires, sheets, and solids. An example was a chair with wire legs, sheet back, and a solid box seat.
Unfortunately, a real-world application never materialized. At one point, I proposed that NMT be used to model machineable models and associated machining processes, but CAD companies were only focused on design, not manufacturing.
Meshes are again making a resurgence with 3D printing. Again, this is based on the basic technology used to process STL files for 3D printing. By the way, most CAM systems operate off of a faceted representation. This is, again, due to the nature of the algorithms not operating directly off of the source geometry and the fundamental geometry of most CNC controllers, which are predominantly lines and arcs. The ability to specify NURBS curves to a controller is a fairly recent and limited advancement.
Defining a spiral staircase with GLIDE
Interestingly enough, it seems that modeling systems cover the two representation extremes (b-reps and facets), but to my knowledge have pretty much skipped over cellular (homogeneous or adaptive) representations, such as voxels [3D pixels] and dexels [depth pixels]. These are gaining some pickup through today’s scanning and 3D printing technologies.
Through all this time, it has been interesting to see the advances on-going in modeling technology. Probably the most compelling is advancing the model beyond just a geometric representation, but also encoding all the corresponding product data. Who knows where this all will lead? Maybe someday geometric tolerances might be encoded in the solid model similar to how RESABS [numeric precision] and RESNOR [angular resolution in ACIS] are maintained.
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There is so much that isn’t known about the early days of the industry. And there was so much shelved back in the day, because the hardware wasn’t up to it. Imagine if someone dusted off that stuff and migrated it to today’s hardware so that, as the saying goes, “Everything old is new again.”
[John Callen is an architect by training, and spent his 40-year career in marketing and engineering positions at high-tech companies. Much of his career was with mechanical design and manufacturing systems, and now he has returned to his architecture roots as Director of eTools Marketing at Lutron Electronics.]
And in Other News
Companies like PTC and Facebook just know that moving to the next level of abstraction gives them an advantage over competitors. They’ll be spending years and billions on Atlas and Metaverse. Companies should understand what their core is, according to Daniel Jackson.
They’ll fail, because full MCAD doesn't belong on the cloud and people don’t wear shoes on their faces. Better technology is not better humaneness. As technology becomes more abstract, Romanticism is the natural backlash.
Take, for example, the natural technological superiority of ebook readers over dead-tree books: even so, ebook titles now cost more, and the digital format is sinking in popularity to paper.
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Cubic Orb’s plugins for land surveying work with most CAD programs, including those based on AutoCAD, IntelliCAD, ARES, Microstation, BricsCAD, and TurboCAD:
KaliBro - georeferences, edits, manages raster images in CAD
GeoView - operates on sets of coordinates in CAD
Wms2Cad - displays maps from WMS/TMS and WMTS services
TranMap - transforms CAD drawings between coordinates systems
And more.
Demo versions are available to download at cubicorb.com.
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Lantek celebrated its 35th anniversary and reported that Q3 sales of its machining software were 30% higher than a year earlier. It has big plans for the future: increase R&D spending by 70% (from what, we don’t know), and adding 130 more employees from the current 260. www.lantek.com
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Open Design Alliance adds a validation engine for IFC [Industry Foundation Classes] files to its SDK [Software Development Kit]:
Performs multi-level validation on IFC models
Customizable for a range of tasks
Supports simple low-level syntax checking
Custom validation defined in IFC files
Higher-level checking specified by the IDS [Information Delivery Specification] and MVD [Model View Definition] standards from buildingSMART.
The validator is part of Open IFC Viewer v22.9, which is available free from openifcviewer.com.
You wrote that the BricsCAD acquisition was “For Hexagon to get deeper into the AEC space.” Did you choose not to comment on this, to give us readers time to mull this over?
I’m interested in knowing what you think about that statement. It's been three years since the acquisition [of Bricsys by Hexagon] and nothing has really jumped out at us yet. - Name withheld by request
The editor replies: Here is my initial take on the statement. From what I see (I am a beta tester of BricsCAD), Hexagon is putting a lot into BricsCAD, and that is the good news.
Hexagon’s origin is in CCM [computer coordinate measurement], which is a post-MCAD process, so they don’t have experience in AEC [architecture, engineering, construction]. They see BricsCAD as the path to entering the market, surrounded by all their other products, like point cloud acquisition and plant design software
Their mirror is Trimble, which started with surveyor’s equipment and is also trying to get into AEC, starting with the acquisition of SketchUp nearly a decade ago. We’re not, however, seeing any impact on the industry, as SketchUp is not a great entry point for a corporation trying to target a discipline dominated by Vectorworks, ArchiCAD, and Revit; SketchUp began as conceptual design software, not as design design software.
BricsCAD has a reasonable chance of making an impact in AEC, but continues to suffer from the same problem it’s always had: lack of mindshare.
I would say the most important aspect of BricsCAD is that it also works as a DWG platform, which is why the CADWorx division of Hexagon fostered the acquisition of BricsCAD in the first place. I am watching to see if BricsCAD-as-platform spreads to other areas of Hexagon, keeping in mind that Hexagon already owns several other CAD packages.
Re: Rådgivende Ingeniørers Forening
Your conclusion could also be “forming purchasing pools” to buy stock in the design software companies, because those companies listen far more to shareholders than to users.
I would guess that the Norwegian government has sentiments similar to the RIF, so perhaps they could pool resources to buy a larger share of Autodesk stock, which would give them a louder voice in how things work at that company. - Peter Lawton
The editor replies: Good idea, but.
There have been suggestions in that past that users buy up a majority of ADSK stock, but that would never happen. Sovereign wealth funds do not interfere with the running of companies.
Mr Lawton responds: Some of the stock-purchase suggestions to which you refer have come from me, as I have been championing that cause for the past 15 years, at least. 😎
However, to state flatly that it ‘would never happen’ is rather defeatist and I would respectfully submit that big companies count on that very attitude to continue to get away with being poor corporate citizens. “What are those two million frustrated users gonna do about (our latest rip-off maneuver), hunh? Fire the board?!”
Well, if those two million frustrated users are also shareholders, the board will be far less dismissive of our requests. Does that make sense? Not everyone connects those dots.
It will take time, perhaps a decade, but if enough of Autodesk’s corporate victims pool enough resources to purchase a significant portion of Autodesk stock, the company will have to listen.
Also, it may be true that sovereign wealth funds don’t deliberately ‘interfere’ with corporate governance, but they do influence it, if only by virtue of their purchase of stock. If RIF writes a letter to Autodesk, and Norway’s SWF (in conjunction with RIF) is holding 5% of shares (about $3.4B today, or 2.6% of the SWF), how do you think Autodesk will react? It’s just a matter of time and money, and there are many parties interested in getting Autodesk to change its ways. All those parties need is organization and patience.
Notable Quotable
“A model is not evidence. It is a theory expressed in arithmetic terms.” - John Hinderaker
Thank You, Readers
Thank you to readers who donate towards the operation of upFront.eZine:
Stephen Schuller
Nicholas Busigin: “Thanks for the great eZine. I enjoy reading it every week.”
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Issue #1,107 | Inside the Business of CAD | 4 October 2021
You’ve probably seen CAD demos that start with a square box covered with grid lines, which are then prodded and pulled to arrive at a curvaceous shape. This is sub-d (sub-division) modeling.
XShape modeler from Dassault Systems interactively editing the body of a remote control with sub-d modeling (image source SolidApps).
In the figure above, the vertical and horizontal lines on the body lay out the subdivisions. The lines in blue are being interactively pushed (by 5.24mm), much like in clay making. The body is a surface model, which can be converted to a solid, if not too complex.
We are so used to working with the precision afforded by profiles and solids (b-rep modeling) that the slapdash nature of subdivisions seems like an unhelpful distraction. Nevertheless, it has its place in the designer’s toolbox.
Here Jonas Kunze looks at the pros and cons of using sub-d modeling for our design work.
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Brilliant concepts need brilliant tools. Otherwise, creative and innovative ideas can fizzle out soon after they emerge. This raises an important question: do designers today have tools that match the creative flair inherent in design as a discipline? I examine the question with reference to sub-division (sub-d) modeling.
What Is Sub-D Modeling?
Subdivision surface modeling is a concept with which designers may well be familiar, since this technology represents the state-of-the-art in digital modeling. The technique comes from character design, and was originally introduced by animation studio Pixar as a faster way to model animated characters and CGI [computer-generated imagery].
With sub-d modeling, shapes are achieved by manipulating control points through several kinds of push and pull actions. The technology is incorporated into a number of software tools used in design, such as freeware Blender (see figure below) and Dassault X-Shape (see figure above).
Sub-d modeling in Blender (image source Konstantinos Karvouniaris)
Advantages to Sub-D Modeling
Sub-d quickly gained popularity due to the time-saving it offers. Its use then expanded beyond character animation (such as in computer-animated cartoons and games) to other industries, such as industrial and automotive design.
The technique includes the following advantages:
Time efficiency. Subdivision modeling is a quick approach to sketching. Once users are familiar with the software, results can be achieved with substantial time savings, especially when compared to other tools like NURBS [non-uniform rational B-splines].
Uniformity. Sub-d performs well when designing organic shapes (such as cartoon dinosaurs) and where little variation is required; this is why it was created originally for animated cartoons. This makes it a fitting tool where overarching symmetry and uniform design results must be created fast.
However, results may be less than ideal when wanting to imprint a unique identity on a product.
Convenience and familiarity. The intuitive nature of sketching in sub-d makes it a convenient choice for designers who are familiar with NURBS tools in CAD. Sub-d is similar to polygonal modeling, making the familiarity factor a plus. For many designers, sub-d is the go-to solution whenever objects cannot be easily modeled with NURBS in CAD, for example in the case of styling surfaces (see figure below).
Overall, we can say that subdivision modeling is suited to tasks where quick visualization results are more important than precision.
Automotive styling with sub-d modeling (image source Adobe)
Disadvantages of Sub-D
We cannot forget that this modeling system was originally developed to recreate organic shapes (a.k.a. human and other non-prismatic shapes). This is very different from the kinds of inanimate objects common to mechanical design, explaining sub-d’s short-comings:
Fast to Slow. Speed is not a constant in subdivision modeling. While getting an initial model takes little time, there is often a speed mismatch between the subsequent stages of the design process; progress in later stages slows down. Sub-d eventually falls short in automotive design, where renditions of concepts become increasingly detailed as ideas are discussed, worked on, and reworked.
Lack of Precision. Speed is important in commercially-oriented processes, but there is a price to pay for sub-d’s time savings: lack of precision. Control and precision are paramount in automotive and other designs as they play a crucial role in defining value and impact the product’s final price. When it comes to using sub-d, there is an implicit assumption that designers will have to accommodate a certain degree of inaccuracy.
Non-iterative. Subdivision modeling does not lend itself well to the iteration loops needed in the automotive design process, because every change requires starting from scratch. As others have stated, one of the shortcomings of this technique is the lack of continuity. So, to add details or make changes in later stages, designers resort to other tools. In this sense, sub-d inserts disconnection and fragmentation into the process.
Many designers agree that modeling tools currently available have important limitations. In the case of sub-d, we cannot deny its usefulness, especially for first-stage visualization purposes. But given its shortcomings, can this technology be enriched, complemented, or replaced? One area where sub-d works well is in interactive virtual reality modeling.
In the absence of a better option, sub-d is the fastest way to generate the impression of an idea. It is certainly handy for visualizing concepts to assess their feasibility. But since this technology is admittedly lacking in dimensional accuracy, is it possible that it has outlived its usefulness?
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Siemens last week expanded its Xcelerator offering by launching “Xcelerator as a Service” or XaaS, software based on MindSphere, Mendix, Supplyframe, and TeamCenter X. It offers collaboration, mechanical design, electronics, and software development on the cloud. sw.siemens.com/en-US/digital-transformation/cloud
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QuadriSpace releases Document3D Suite 2022 consisting of Pages3D for technical documentation and Publisher3D for technical illustrations. The new Detail View Markup creates illustrations with zoomed views of 3D models.
A new part filter sorts and identifies parts meeting user-defined criteria. Part metadata can be imported from and exported to Excel for access to ERP and PLM data. Thirty-day demo (after registration) and more info from quadrispace.com/products/whats_new_2022.
Letters to the Editor
I’ve been watching the consolidation of the CAM [computer-aided manufacturing] industry with great interest.
Companies have acquired an extensive portfolio of CAM products, but for the most part have been unable to consolidate them, due to their inherent proprietary nature. The proprietary approach ensures that manufacturing knowledge encoded into each resides solely in each.
Much like CAD systems of the past were faced with a similar proprietary representation which locked users into their platform, which encouraged [intermediary] data exchange formats, this CAM consolidation could also be the motivation for a CAM interoperability standard. Such a standard does exist in STEP-NC, an ISO standard which would provide a neutral file format to exchange process data between CAM systems.
Maybe the time is right for STEP-NC -- depending on whether the acquirers are looking for ways to consolidate their CAM assets. - John Callen
The editor replies: Software companies that are acquiring CAM software would want something like STEP-NC, but I am finding that data integration between acquired companies (under the larger entity) is an inexplicably slow process. (Nemetschek Group might be the poster child for this.) Perhaps this is why Autodesk rips its acquired software apart!
Investment companies that acquire CAM software would not care about integration.
Mr Callen responds: You're right. Investment companies that just want to milk the cash cow, and would not care about interoperability within their portfolio.
Though STEP-NC could provide interoperability across a vendor’s CAM portfolio, it would also potentially allow migration to a CAM product outside the portfolio. MCAD went through a similar cannibalization scare, which really didn't materialize. Users still like to use what they like to use.
Re: A.I.’s Fatal Flaw
In upFront.eZine issue 1,105, you wrote “The blackbox crutch executives can say decisions were made by AI, and so deny culpability.” This is the Sergeant Schultz Defense (“I know nussink”) and it usually fails. See en.wikipedia.org/wiki/Idiot_defense - Don Beaton
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For all my techie friends: a great article by CAD’s equivalent of Gandalf the Grey. What is AI, and what has *really* been accomplished so far? - MattyKUSA via Twitter
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You wrote: “We see obsessiveness over AI because it is the ultimate computing problem.” This is truly a factor, but so are economics. Investments in technology are made in hopes of strong returns on capital. Technology has profitably replaced a large chunk of the muscular tasks that were once the province of humans.
The big economic opportunities now lie in replacing intellectual labor, which is generally expensive labor. Computers replaced plenty of intellectual work already. I once worked in an insurance company; by 1980, the sea of clerks of the earlier era had largely been replaced by mainframes and a lake of programmers. Now the less repetitive, more complex intellectual labor is where the opportunities are.
As for CAD, while I am sure that AI will power certain tasks, AI is far from being able to do the core work, which is design. Certainly in AEC, we are far from organizing all the disparate knowledge that underlies a design in a manner such that AI can use it.
We already see this problem in BIM, where BIM evangelists and salespeople want to credit BIM for benefits that substantially arise from Integrated Project Delivery (IPD). IPD is the only current way we have to get all the needed knowledge into the design, which is not to ignore things like automated checks for building code compliance.
Lastly, as a species, we are going through plenty of changes of what it means to be human. A few years ago I was astonished to read that significant numbers of teens were more comfortable texting their friends than speaking with them face-to-face.
Back in 1976, Joseph Weizenbaum published Computer Power and Human Reason. In the mid 1960s he had invented (designed) what we today call a chatbot. ELIZA was a very early piece of AI (See en.wikipedia.org/wiki/ELIZA for details.)
At that time it operated using a teletype machine interface. In one version ELIZA acted like a psychotherapist. Weizenbaum was struck, and alarmed, when his secretary developed a strong emotional attachment to the program. Thus his book, which raises the now-old and still unresolved question of how we will be changed by what we have created. - Leo Schlosberg
The editor replies: I remember running Eliza on the university mainframe computer at in the late 1970s. It very quickly became repetitive in its answers.
I don’t think that humans change in reaction to new technology; we adapt. For instance, our fingers gained muscle memory for touch typing, and then for typing on small glass screens.
Mr Schlosberg responds: What got Weizenbaum going was the secretary’s (and other people as well) reaction and attachment.
The specific version was one that mimicked Rogerian therapy (pioneered by Carl Rogers, also known as “nondirective therapy” or “client-centered therapy,” and based on pretty much rephrasing what the person said in an affirming way or asking modest questions, like “How did that make you feel?”). That may be the ELIZA you met but possibly it was a different version.
I almost wrote you today after seeing a few articles on AI. One was in an archaeology magazine about an application in which the AI was better than archaeologists at matching pottery shards. That, plus your article got me to checking in on radiologists, who surely are ripe for substantial displacement/replacement by AI.It was in a professional publication and not very incisive.
The editor replies: Humans yearn for non-human attachments, because they are faithful and cause no problems, the way that other humans do — like a dog, but without the problems dogs create.
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Nobody is better than Ralph Grabowski at telling the emperor of software he has no clothes. Worried your job will be replaced by a computer? Take 5 minutes and read Ralph Grabowski’s "AI's Fatal Flaw" and you’ll feel a lot smarter. - Roopinder Tara via Twitter
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With Minsky, perhaps we just misinterpreted his “Within a generation.” Assuming the human race survives, it will happen within a generation. We just have no idea which one! :) - Robin Capper
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I've been relying on Ralph Grabowski's commentary on the CAD industry for nearly three decades just myself. He never fails to provide something new. Here, I learned two new terms that describe the AI crutch:
The Black Box Crutch
The Boombox Crutch - Darren Young via Linked-In
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Is today’s AI just a collection of rules and parameters, that the computer uses as boundaries and never forgets? If so, should we not call it artificial ‘intelligence’, but just ‘artificial rote memorization’, or “ARM” ? - Peter Lawton
The editor replies: True AI would make inferences from data presented. Problem is, if it were to do that, we would have no idea how it arrived at its conclusion, and so would be unable to confirm if it was correct.
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Another eloquent and insightful piece of writing. Common sense in this industry is getting to be uncommon. - Jess Davis
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I agree with most of what you say about AI. I do believe that advances are being made. I saw this on a blog and thought it was pretty amazing: “OpenAI Codex Live Demo.”
- Conan Witzel
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A friend of mine said around 1990 the ultimate sentence about AI, which has been true since then, and always will be, more so than Moor´e’s Law: “Artificial Intelligence is everything computers still cannot do.” - Fernando Valderrama
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I have enjoyed reading your upFront.eZine for most of its 21 years. Having corresponded with you previously, I feel you will find the discussion linked below to be interesting and informative: Online Conversation: Understanding Transhumanism.
Best line in your article: “What is AI’s fatal flaw? It cannot replicate human metaphysics; the rational cannot conceive of the irrational.” Many thanks for your excellent journalistic efforts. - Harold Chaney
The editor replies: The video notes that an alternative name proposed for AI had been “complex information processing,” which would be more accurate, but that “artificial intelligence” was considered more aspirational. “There is something about a term about something that we can’t achieve that inspires people to think beyond existing constraints.”
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Your writing about AI in your latest issue is excellent. Thank you for your voice of human rationality (or is it human irrationality, or both?). A much needed dose of whatever it is (intelligence). - Rob Snyder
Notable Quotable
“If people yelling on Twitter can cause policy change at Apple, imagine what will happen when nation states exert pressure to increase the scope of on-device searches.” - Diogo Mónica
Thank You, Readers
Thank you to readers who donate towards the operation of upFront.eZine:
Michael Kuzmik
Jeremy Powell at Vectorworks (large company donation): “Keep up the great work on upFront.eZine, Ralph!”
To support upFront.eZine through PayPal.me, then I suggest the following amounts:
Issue #1,106 | Inside the CAD Business | 27 September 2021
Guest editorial by Dave Edwards
Back in the day, most CAD output was done on pen plotters driven by DOS-based software. Yes, there really was work done before the advent of Windows and the Mac, done with real pens and real ink. This was long before PostScript printers and standardized font formats.
The font format developed by Autodesk for AutoCAD, for instance, is named SHX [short for “compiled shape”]. This is a vector-based font format, which uses only lines and arcs in character (or “glyph”) definitions; no fills. See the figure below.
To get different font weights on the output, specific pen numbers were assigned. To draw a thicker line, you specified a thicker pen, and then the CAD program literally instructed the plotter to pick the specific pen from the pen carousel. See figure below.
Carousel holding pens of various weights (image source softsolder.com)
A typical carousel held up to eight pens of different sizes placed in numbered locations. The sizes were based on standard drafting pen sizes: 0.25mm, 0.35mm, and so on. In the CAD software, you placed all entities that needed to be drawn by a specific pen width on their own layer. It was very restrictive, and pens running dry were a royal pain. This changed so much for the better when inkjet plotters came on the market.
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As font technology developed, the need for WYSIWYG — What You See is What You Get — displaying of fonts became standard. But it was still a while before you could see the effect of adding a pen weight to a font on the screen. VersaCAD was an early exception, as it had a system by which the user could select the output scale and it would display the desired pen weights on the screen.
Special Character Standards
When the first CAD systems came out, there was only the ASCII standard for character codes. This was carried over from teletype machines: when a letter was pressed on one machine, the same letter would be printed out at the receiving end.
But ASCII had specifications for only 128 characters, of which the first 30 were for controlling the teletype machine. In CAD, the immediate need was for special characters, such as degree, plus/minus, and diameter. What Autodesk did was add these characters to specific locations in their font definitions.
Later, when the ANSI code was developed for handling 255 characters, it added mostly foreign characters and still there was no location for diameter. (Don’t get me started on using “O-slash” for diameter!)
The advent of modern font formats, such as Postscript and Truetype, permitted large sets of international standards and so Unicode was developed by an international committee. The committee determines character locations for foreign, technical, and graphic characters. Using this system, a font developer can create a font with special characters in these defined locations; applications that want to display those characters know which codes to use when calling a font.
How Many Characters? Where’s the One I Want?
Unicode originally had about 62,000 characters; the latest version has specifications for over 143,000. But this doesn’t mean that all fonts have all characters. The Unicode version of the “universal” Arial font, for instance, has only the original 62,000.
Having been a member of the Unicode Consortium in the past, I’m familiar with the process of adding characters to the standard. Applications are submitted each year and then they are voted on. If you ever have the chance to go through the Unicode standard, you’ll see enormous character sets for language systems, such as Japanese Kanji, and even more for “artist” systems like Klingon. (It was never approved.)
The current version of Unicode covers most of the characters needed for architectural projects, but not all of them. This is where it gets hard for users and for CAD/BIM applications. What happens when the font I need to use doesn’t have the character I want?
Most of the “big name” fonts should have most of them. When they don’t, the CAD application handles things in a couple of ways:
First, fall back on characters that look similar. For years AutoCAD had the error of using the “null character” location for the diameter symbol. Many fonts had diameter, but not the null character; in this case, AutoCAD punts on one character location and uses another. Often, this has to be done for several characters and rolling back to several other lookalikes.
Next, fall back to characters in a different font known to have the characters needed. AutoCAD does this with ISO fonts, but this can look terribly strange.
There’s a major problem when the character you need has no Unicode specification and so is not found in any major font. This is the case with the 1/16 and finer fractions. Unicode specifies fractions up to 1/8 and related fractions, but not 1/16. What most CAD systems do is fake fractions by drawing them using individual characters — but that can look weird too.
The Real Issue is Height
The real problem with fonts in CAD and BIM software is scaling. This is especially important when going from one CAD system to another. SHX fonts are still used frequently in DWG programs, such AutoCAD; these fonts use a different scaling method than Truetype fonts.
As SHX characters are composed of just lines, the height of characters are set to the exact height of uppercase letters. See figure below.
CAD defines the size of text by the height of capital letters
This is, however, not the case the desktop publishing fonts. To understand why not, let’s look at how typography works.
A Bit About Typography
There’s an ancient history that sets standards for typography, which poses problems for the CAD world. When it comes to sizing characters, what is important is the distance from line to line, and not the size of the uppercase letters. In laying out text for printing, the lengths of columns need to be maintained, no matter which typeface is used. In fact, font designers can make the size of uppercase letters any height they wish.
When the size of a font is specified for printing, point size is used (72.72... points to an inch). But this determines the spacing between lines and not necessarily the size of the characters. Huh??? As a CAD font designer myself, it took me years to wrap my head around why it is done this way.
Go into any word processor and pick a handful of typefaces and insert a few capital letters. I created the text seen in the figure below in Microsoft Word, setting the size of the large letters to 72 points. Notice that each one has a different height.
Microsoft Word drawing the capital letters of different fonts at 72 points
So how do you create Truetype text at the correct size in CAD when a contract requires all text be 1/8" tall? This is the trick most CAD and BIM application use that causes the problems:
They inspect the curves that make up one of the characters to determine its actual size. AutoCAD uses the character “A” but the letter “M” should be used, as has been historically done in typesetting.
The application then scales the text slightly up or down so that the size of the characters are at the right size. The figure below shows how the same text appears in AutoCAD:
Autodesk AutoCAD drawing the capital letters of different fonts at 72 points
This poses the next problem when drawings with text are imported into other CAD systems that use different scaling mechanisms. You most likely see this when you use SHX in one application and an equivalent Truetype font in the receiving application. Because Truetype fonts are created using boundaries, CAD often scales them down the text to account for the height of uppercase characters.
The good news is that it has gotten better over the years. For instance, the developers of Revit first used a different scaling system than did AutoCAD. A few years ago, Autodesk changed the font scaling in Revit, which made for loads of fun fixing all the files.
(Years ago I created a system for converting SHX fonts to Truetype format. It’s a very long progress with many steps. The biggest issue is getting the math correct when a boundary is added to characters to correctly compensate line lengths as heights of uppercase characters are reduced. I created a Truetype set to substitute for standard SHX fonts RomanS and Simplex. If you’re interested in them, contact me.)
So, What’s the Point?
I just wanted to get this information down so that whenever a question about fonts arises, users will have the information at the ready.
BIM is supposed to collaborative, yet text fidelity is a stumbling block. The round trip of CAD to BIM to CAD can be a nightmare.
This is why most users landed on using something like Arial for all their work. (It is a modern clone of Helvetica, and it’s a boring-looking font.) Arial has some disadvantages when used for technical documents, but it’s become a standard.
Just know that in most applications, you no longer have to be worried about how the fonts are created to get the correct size.
Industry Musings
Having fought the good fight and lost over much of this, I naturally have opinions about all this.
In all these years, too much has been just a patchwork-kludge. We have Unicode characters for much of what we need. Why are they not being used? Feet and inches marks used in dimensions should use the prime (') and double prime (") characters, not curley quotes (’ or ”). AutoCAD’s SHX fonts don’t have copyright, registered, or trademark character — just to name a few.
There needs to be an industry committee that specifies font standards for CAD and BIM. Its role would be to brand fonts approved for having specific sets of characters and sets of internal heights, so that scaling no longer is an issue.
There’s a section in Unicode called a “Private Dictionary,” which AutoCAD uses for locations of needed characters not found in Unicode. There needs to be an effort to get more of these characters to have set locations and then get them published, so that font designers can create their fonts with these characters. This is already being done for fonts needed in music publishing.
The Bottom Line
For BIM really to be a collaborative venture, it needs to put into place several standards, and fonts is one of the basic ones that has been overlooked. CAD firms felt that by simply adopting Truetype (and not even OpenType) they covered the issue — not so!
I did what I could while I was still more active, but it fell mostly on deaf years. Vendors have had more important functions to get into BIM, such as handling big projects and multi-user collaboration. Some of the nuts and bolts have, as a result, been left in the dust.
END RANT
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Dave Edwards develops Project Newplex, an advanced SHX font for technical documents. He is an application feature consultant and technical documentation writer. You can contact him through [email protected].
[This article was reproduced with permission from PADT, the Prag Arch Design Tech newsletter in which Mr Edwards explains how to make BIM work. I find it very useful. View his articles at pragarchdesigntech.substack.com.]
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Vectorworks launches the 2022 editions of its software:
Architect
Landmark
Spotlight
Fundamentals
Braceworks
ConnectCAD
Vision
Vectorworks Designer has been renamed “Vectorworks Design Suite.” Vectorworks is the first major BIM application to run natively on Apple silicon processors, running some processes 4x faster. vectorworks.net/en-CA/2022
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Here are some of the posts that appeared recently on my WorldCAD Access blog:
I thought you might find this interesting, if only to illustrate how some in the academic corner of the computing world view CAD: “A New Era for Mechanical CAD” at queue.acm.org/detail.cfm?id=3469844 by Jessie Frazelle
A few eyebrow raisers, such as “instances” vice “blocks” and missing things like the Blockify command in BricsCAD or any mention of LISP, etc. The author is evidently not a CAD-slinger. - Richard Webb
The editor replies: Her primary concern appears to be that because CAD is so old, it is not capable of modern computing, such as multi-core. The problem with her argument is not the age of the code (which has been refreshed over the decades) but CAD’s inability to predict user operations, and as a result cannot run on multiple CPU cores.
I have a similar problem with my M720 Logitech Triathlon mouse. Initially I connected with Logitech’s Unifying USB receiver, when it started doing awkward things in clicking and dragging. Sometimes it didn’t respond with click, but after a while it jumped like I was rapidly clicking.
After I read this thread, and found the comments by H. R. Puffenstuff, I tried switching the connection to Bluetooth and discarding the wireless Unifying USB plug. Then it worked right. It works well, like my first use of wireless USB.
Hence I conclude this is the USB receiver’s problem. Thanks for the inspiration. - Adi Dewanto (via WorldCAD Access)
Congratulations Ralph, this is a VERY impressive body of work which helped (hundreds of ?) thousands of people become proficient in CAD! - Malcolm Davies
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I wish that Bricsys would team up with you again. Not a fan of the current documentation. Web pages are a pain to navigate and, of course, impossible to highlight and add notes to. The auto-generated (apparently) off-line help files are... not good. - Richard Webb
Notable Quotable
“So when big corporations accuse you of copyright infringement, you can get fined, lose your Internet access, lose all income from your videos, be blocked from the platforms where you make your living.
“But when big corps infringe on our copyright, the war on piracy is forgotten.” - Nytt år, samme Børge
Thank You, Readers
Thank you to readers who donate towards the operation of upFront.eZine:
R L Capper
Stanley Przybylinski
To support upFront.eZine through PayPal.me, then I suggest the following amounts:
Issue #1,102 | Inside the Business of CAD | 28 June 2021
David Stein: I’ve been preoccupied with non-CAD work for too long and only recently checked in with your newsletter to catch up on things.
The more I read about big-name CAD producers, the more it seems they chase bigger spenders, rather than focus on customer needs, especially small and mid-sized customers, who can’t justify selling their homes, kids, and pets to buy super high-end hardware and insanely expensive products.
Catchy names, rehearsed speeches, coached hand gestures, and overblown claims during keynotes are boring. It’s become like CGI [computer generated imagery] in action movies: nobody jumps in their seats anymore, because they know it isn’t real. Keynotes are all aimed at the executives, not the engineers and designers.
I never rooted enough for the underdogs; many have come and gone. But I hope to see a new generation of CAD products priced lower than a new home roof. I’ll gladly try something that can model a house deck, or custom-furniture piece making, if it's inexpensive (or even free).
But right now I’d rather draw my 3D plans on paper than pay thousands of dollars. I don’t need to collaborate with a marketing team, or to print parts in outer space — just basic machine shop stuff, the people they seem to have forgotten about.
Ralph Grabowski: You are seeing this frantic behavior because some publicly-owned CAD vendors are getting financially desperate as they run out of revenue boosters in what is a mature market. We saw prices increasing steadily through a variety of tactics:
Some CAD vendors forced users off one-time permanent licenses and onto all-the-time subscription fees.
They skyrocketed subscription prices for big enterprise customers, who typically renegotiate licence fees every third year.
They increased the effective cost of networking licenses by changing them from floating to per-person.
In the last fiscal year, they received a one-time big bang by being allowed to report deferred subscription revenue differently, in a way that makes it look like they goosed revenues during the pandemic.
One editor, who has his pulse on the industry more than me, thinks the next step is consumption-based use. The more cloud-CPUs your drawing needs, the more you pay — possibly through tokens, which some CAD vendors have already implemented in a limited way (such as for renderings and generative modeling).
In a perverted way, the money grab make sense, as certain CAD vendors have painted themselves into a corner. After convincing themselves that the cloud was to be the Next Big Thing, they forgot that they are the ones footing the bill 24/7 to Amazon AWS. Now they are scrambling to figure out how to cover their sky-high server bills. The answer: squeeze the customer.
CAD vendors who are keeping their software on the desktop are smart. They don’t incur the AWS tax.
David Stein: Oddly enough, I left the world of CAD (add-on developer, actually) for IT infrastructure, and then cloud — mostly Azure and the Microsoft stack. It’s interesting to me that for all the touting of “consumption-based pricing” by Microsoft that they don’t follow their mantra completely. There still are upfront costs like Security Center. Azure Log Analytics features, such as Change Tracking, incur a node fee.
I think that both markets, CAD and cloud, desperately need more competition. It’s shaping up to be like the big three TV networks from the ’50s to the ’70s.
Ralph Grabowski: Big shifts promoted by CAD vendors today inevitably become minor components tomorrow. There was a time around 2000 when we were so bombarded with collaboration-as-the-future marketing that we began referring to it as “the C-word.”
The ceo of a CAD firm one said something along the lines of, “If you’re not giving me money I don’t want you as a customer.” He did not seem to understand that it goes both ways: if CAD vendors aren’t giving value for money, then customers don’t want them a suppliers (cf. the Revit letter).
And in Other News
Open Design Alliance is looking for companies to work on a general purpose scan-to-BIM SDK [software development kit] that would do the following tasks:
Convert point cloud data to segmented meshes
Remove interference objects
Classify meshes into objects like walls, doors, and windows
Convert classified objects to BIM formats like IFC and RVT
Even though some CAD vendors have already implemented scan-to-BIM functions on their own, this collaborative effort is meant to provide it faster and more cheaply than doing it from scratch. Members will write the source code and determine the usage fee. More info about the initiative is at opendesign.com/scan-to-bim.
Epson is launching six new models this year of its SureColor T-Series inkjet printers in 24-, 36- and 44-inch sizes. First up is the T7770D (US$6,945) 44"-wide printer that holds two rolls of paper, a take-up reel, and an optional stacker. It prints monochrome CAD drawings at speeds of up to 1,400 square feet/hour.
Issue #1,100 | Inside the Business of CAD | 14 June 2021
Written by Gustav Näslund
Mathematics software for engineers is not something I am especially familiar with. When I took calculus, we had no calculators, and in my field of study at the time, transportation engineering, we tended to work with simple trigonometry, rather than advanced equations.
So, reader Gustav Näslund suggested running an article about the software available in the engineering math editor space.
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Software for engineering math are not strictly CAD, but I think nonetheless that they are essential and powerful tools for design engineers to perform and document engineering calculations.
I think this class of software is not as well known, nor used, as much as it should be in our industry, which is why I would like raise awareness of them.
If you are not familiar with this kind of software, think of it as a free form digital notepad that does calculations interactively. It supports units of measurement and live links between all variables and equations. The figure below is typical:
Math software doing calculations and units conversion
In general, this kind of software lets you add equations, text, and images in a freeform manner, and you can rearrange them as you like. All equations are live-linked, so that they update their values when something changes.
Because you work in a paper-like format, the format is self-documenting. When you are done, just save it as a PDF file, and you have your calculations documented.
The equations support all units of measurements. This means, for example, that we can mix imperial and metric units in equations without fear. The mandatory reference here is to the NASA Mars Climate Orbiter debacle; see en.wikipedia.org/wiki/Mars_Climate_Orbiter.
I find that the programs have a very low threshold for getting started, and run fast, so they are suitable for even the simplest calculations — never mind the most advanced.
Math Software Packages
The figure below is of SMath Studio; MathCAD and Maple Flow look similar.
SMath Studio from Andrey Ivashov
MathCAD has long been a player in engineering math editor field, 35 years in the business. It was taken over by PTC in 2006, and then received a total makeover as MathCAD Prime in 2011.
The latest version of MathCAD is available now by subscription only, in the ballpark of $1,000/year for a commercial licence. Educational licenses are available. www.mathcad.com and en.wikipedia.org/wiki/Mathcad
Maple Flow is a very recently released (2021) direct competitor to MathCAD from Canadian company MapleSoft. It appears to me to be aimed directly as a competitor to MathCAD, as it has a very similar interface and works in the same way.
Maple Flow seems to be priced at $2,390 for a single perpetual commercial license. Educational licenses are available. maplesoft.com/products/mapleflow
SMath Studio is a free alternative created by Andrey Ivashov, first released in 2006. It has capabilities that are very similar to the original MathCAD, before its remake as MathCAD Prime.
Being free, it is not as advanced as MathCAD, but for 90% of engineers it will be just what they want (and need). It has a thriving community that creates plug-ins and so on, and is funded through donations. www.smath.com
[Gustav Näslund owns GN Tech of Sweden, and specializes in product development and mechanical design. www.gntech.se/en]
And in Other News
The next release of NX is shipping later this week on June 18, while Solid Edge 2022 is scheduled to become available later this year in October.
In other Siemens news, the company acquired Nextflow Software of France for its meshless simulation technology. Smooth-Particle Hydrodynamics does particle-based computational fluid dynamics for gas and liquid flows. www.nextflow-software.com
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Radica Software’s Electra Cloud schematic electrical design software now exports BOMs (bills of material) directly to OpenBOM for report creation, with further links to accounting systems. A future upgrade will export data from OpenBOM back to Electra and its Vecta.io SVG [scalable vector graphics] editor. radicasoftware.com
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3D Systems has divested itself of its on-demand additive manufacturing service, named On Demand Manufacturing, for $82 million to Trilantic, which promptly renamed it Quickparts. Details at schnitgercorp.com/?p=18523
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Jon Peddie Research reports that the GPU market last year grew by 39% to 199 million units. The market share between suppliers remains unchanged:
Though well outside of my profession, I find FEA [finite element analysis] interesting. Does Coreform run on GPUs [graphics processing units]? I searched their forum for the term, but there was only one unrelated result.
How does the speed of their software compare to competitors that do run on GPUs? Many FEA software packages are optimized to run on nVidia GPUs: nvidia.com/en-us/gpu-accelerated-applications.
It would seem that if their core calculations are more efficient on CPUs, writing the code to get their software to run on GPUs would be a further advantage. - Peter Lawton Affiliated Engineers, Inc.
Greg Vernon replies: Currently, we only execute on CPUs, but we’ve architected our algorithms and code to be maximally parallelize-able. GPU-compute is definitely on our roadmap.
A large bulk of our compute time is spent within the linear and nonlinear solvers provided by the open-source PETSc project, which is currently developing GPU support. See mcs.anl.gov/petsc/features/gpus.html.
We’re currently focusing on classes of problems that have [in the past] required incredible amounts of compute resources, but rather than throw more resources (more CPUs and GPUs) at the problem, we’re consistently finding that throwing better math at the problem is giving us orders of magnitude faster solves.
I like to think of it in terms of Exascale* ambitions. If the point of Exascale compute is to solve problems, then there are two ways to achieve this:
Build faster/larger parallel computers
Use better mathematics that make the problem smaller for existing computers
We’re taking the second approach! -Greg Vernon, director of product management Coreform
*) Exascale = computing systems capable of calculating 10¹⁸ floating point operations per second, or more.
Mr Lawton responds: The two approaches are not mutually exclusive, of course, so Corefrom may consider using both — the outcome will be even greater advantage over competitors.
It sounds, too, like the math they are improving requires a different coding team than would be required to get Coreform to run on CUDA, so the two improvements can happen in parallel, once you have the right personnel.
Notable Quotable
“He’s at home recovering for a few days. He saw an offensive tweet.” - Management Speak
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