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altoids

Wrong Line Thickness (revisited)

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There is a fundemental problem with the way Vectorworks (11.5.1 on OS X 10.4.2) determines line thickness for all lines that are not orthogonal. I have read the re-occuring discussions about line thickness, 45 degrees lines, pen shape (round or square tip), Apple QD, Quartz, HP printer drivers, etc., etc.) but the error seems to me to be with Nemetschek. I'd be delighted if this were not the case, as I would be able to produce plots with consistent line thickness; a minimum requirement of a CAD program. Forget new pseudo-hand rendering filters, just fix the basic, enduring bugs in your software to keep your customers, well, customers.

If you look at any plot created by Vectorworks, it can easily be seen that the the stroke thickness is greater on the diagonal lines. This is not in dispute and can be reproduced easily.

Within Vectorworks draw a few lines at different angles and an oval, and at different line weights, print to a PDF, then open the PDF with Illustrator. Zoom in and the errors can be seen, which become even more obvious if using Illustrator's "Outline" feature, which removes line weights and fill colors and reveals just the pen strokes (in Illustrator, select "View>Outline" from the main menu bar). This will show that Nemetschek converts diagonal lines into outlines with a filled area, but with a reduced thickness to try and compensate for incorrect line weight error.

While in Illustrator it is possible to draw exactly the same series of lines without the angle-dependent width error. Lock the imported layer, set up a new layer in Illustrator and trace over the lines. When complete, move the new layers so that the two layers do not overlap. Make sure to set some of the lines to a thick stroke. Print the page (or zoom-in) to witness the Illustrator lines having a consistent thickness at all angles & shapes, unlike the ones created with Vectorworks.

There are many graphics programs on the Mac that do not demonstrate Vectorworks' faulty behavior. As an architect I am most interested in producing accurate plots. I feel cheated having paid money for a drafting program that does not draft the thickness of line I draw. From the discussion boards, this is an old and ongoing problem that should have been fixed long ago.

As Printing from Illustrator does not display this same line-weight error, it is very unlikely that the problem is anyones but Vectorworks. Why does Illustrator not display the problem? In a nutshell, it avoids this problem by rotating the pen tip at the same angle as the line being drawn, just as you would do by hand when drawing with a chisel-tipped pen. This creates lines that are always the same thickness, no matter what angle.

If Nemetschek would rotate their pen when drawing angled lines, the problem would dissapear. Or they could drag Vectorworks kicking and screaming into the 21st century be giving up on QuickDraw (Apple's '80s & '90s era drawings libraries) and instead relying on Apple's newer Core Graphics technology and its component Quartz 2D.

If anyone would like copies of the demonstration Vectorwork and Illustrator files, I'd be happy to oblige.

Katie, if I am missing something, I humbly appologize. But if I am correct, could you let us all know when this will be fixed?

ref:

45 degrees discussion

wrong thickness

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I don't have the problem described (I work on a PC; diagonal lines display thicker on screen but print at the proper thickness on any printer I've ever used). But out of curiosity I followed the two links provided.

Imagine my surprise when both of the linked threads ended in a solution to the problem, and the second one even included a link to a third thread, called "Diagonal Line Thickness Issue Solved!"

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Thanks for the response jan15.

Were it so. Upon reading the link, I too thought the printing error would be solved. While the results are improved by using the link's recommended "Rastering", it is not cured. The diagonals and circular strokes are still of different widths, albeit less visibly so. The print-to-PDF-and-examining-the-file-in-Illustrator confirms what can be seen visually from a print; the same line drawn at different angles is still rendered with different widths.

As the "Rastering" kludge does not address the cause of the problem, it cannot correct the fault. The "Rastering" print option only partially relieves the symptoms and is at best a work-around, not a cure. Rastering has other disadvantages such as generating enormous PDF files, being an order of magnitude slower to print, and being a memory hog. A typical "Raster" print for us increases Vectorworks memory requirement by about 500 MB while rendering. A large print uses up all of the free RAM and require page-swapping taking an enjoyable coffee break to print. A batch print of these files would waste a day. Besides, we are often rushing to print at the last minute.

I do not think that I am being unreasonable if, having specified that a line is .35mm thick, expecting it to actually be .35mm thick when printed using a $1000 software package. My copy of Vectorworks did not come with a warning stating that angled lines would be rendered incorrectly.

A simple analogy. When my building's elevator breaks, walking up 5 flights of stairs to get in to my office does not fix the elevator, though it does allow me to keep working. A work around, not a solution. If the building manager does not try to fix the problem within a few hours, his phone starts to ring off the wall.

Technically, I believe the "Rastering" kludge attempts to minimize the line weight problem by drawing the print file as one enormous, high resolution bitmap (pattern of dots) and then reducing the size of the bitmap to the printed page size. This trick minimizes rounding errors inherent to Apple's old Quickdraw libraries. (Am I wrong Katie?) If this is accurate, then using Apple's updated libraries that draw with real numbers, rather than integers will help solve the problem.

If I am wrong, my most sincere apologies.

P.S. jan15, I have the same screen problem as you, but I do not use the "Zoom Line Thickness" option so this does not bother me. But the error is there all the same.

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I noticed that in one of those other threads Katie said the diagonal line glitch was an issue between Apple and the printer manufacturers. I got the impression from reading both threads that the on-screen increase in diagonal line thickness might be connected to Quickdraw, or Quicktime (are they related? The PC version uses Quicktime), but that in the case of print-out it's a system-to-printer problem. That seems born out by the fact that the display problem exists on both platforms, but the print-out problem occurs only with Macs.

How times have changed, when a graphics program, especially one originally designed for the Macintosh, prints better and/or more conveniently from a PC.

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Sad, isn't it. But this problem is particular to Vectorworks, not the Mac. And it occurs because Vectorworks is using legacy code.

I downloaded a 15-day trial version of some other cross platform CAD package (whose name rhymes with "blurboSAD") and it does not have the diagonal line thickness problem. Although this software has many limitations, it does rotate the pen/nib at the angle of the line to create accurate line thicknesses. When drawing ovals, it segments the oval into many small pieces and rotates the pen for each piece. When an angled line meets a straight line, the endpoint is not orthogonal (just like using a calligraphy ink nib), but this can be rectified by "capping" the endpoints with either a round or square shaped mark (as some other Mac CAD programs do).

Thus, this is an soluble problem, and not a problem between Apple and the printer manufacturers.

I did a little web searching and found that Apple's square pen line thickness problem is an old well known ( Google "quickdraw square pen" ). Interestingly, Quartz (Apple's 5-ish year old OS X imaging technology) does not display this problem, as it is very similar to Display Postscript, which is very similar to Postscript, which is the basis for PDFs.

To answer your question, QuickDraw was Apple's 1984 (and later) collection of graphic routines that programmers could call to do the hard work of displaying graphics. (BTW, Quickdraw was "deprecated" by Apple shortly after they introduced OS X.) A programmer could write something like "move (0,0); line (100,100)", and the computer would generate a diagonal line at 45 degrees starting at the origin in a window (a new-ish concept at the time, at least on a PC). There was more setup involved, but this is the basic idea. The programmer did not have to think about which dots on the display to turn on, how to clip the line if it ran outside the window, and so on. In 1984 this was a great step forward. It is impressive that Apple implemented a square pen of variable size as concurrent graphics system often had just a 1-pixel pen for all drawing. Having control of fonts and graphic was a thrill unto itself. But by the mid 80's, the limitations of Quickdraw were apparent and (I believe) two Apple employees left the firm and started Adobe and proposed Postscript as a device independent vector graphics language. Apple adopted Postscript as the imaging language for their high end printers, and digital graphic design was born. For the last 20 years, it has been possible to generate accurate diagonal lines from a Mac.

To answer your question, QuickTime is a collection of media handling software and libraries that was a develop by Apple in the early '90s (I might be out a few years), and then stolen by Microsoft, (settled out of court after years of legal battle). It is responsible for playing "media" ?essentially movies and music? in real time on a computer, without much programing difficulty. Roughly, a programmer needs only identify the source file and the destination window and size, and hit the "play" button, and QuickTime takes care of the rest. No small feat, even now. QuickTime used to use QuickDraw library calls, but I believe once it became cross platform, Apple rolled it into its own independent thingy.

So back to you Katie. Could you please let us know when Vectorworks will be updated to draw lines at their correct thickness? And again, if I am wrong, I will publicly apologize, bow deeply and promote Vectorworks to all.

refs:

QuickDraw

Apple's QuickDraw page

Apple's OS X imaging technology (Quartz)

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Thanks for the information, Altoids. But I'm still trying to figure out why VectorWorks on the PC doesn't have that problem. Do you know?

Also, I just discovered something very interesting while experimenting with this issue. VectorWorks on the PC no longer has fat diagonal lines even on the screen. Not even VW version 8! But I remember the problem vividly. I can only assume that it was there when I ran Windows 98 but went away with Windows XP.

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Jan15, I am not a PC guy, so I'd have to guess why the PC doesn't have this particular problem. Most likely, Microsoft has updated their libraries, or possibly Vectorworks has rewritten their drawing routines for the MS versions of Vectorworks (highly unlikely). I suspect that Microsoft updated their drawing libraries to perform an auto pen rotate, or they may now be drawing with a virtual round-tipped pen. What shape are the end of your thick, diagonal lines?

All platforms, Windows and OS X included, are constantly improving and expanding their libraries. Typically every time a major operating system release comes out, it is the libraries that are changed, which allow us, the end users, to have funky new features as soon as the software companies rewrite their code to use the new libraries.

At the same time, the platform shelves the old routines, or "deprecates" them, to use the current terminology, allowing old programs to still access the old libraries, but warning developers that the libraries will not be supported in the future. Apple supports old library calls for many, many, many years after they have officially stopped supporting them, allowing old software to run on new systems. I can still run WriteNow, a Mac word processor from 1989, on apples latest system, OS X 10.4.2. MS is happier breaking old software, forcing software companies to rewrite or at least recompile their software.

Because of Apple's legacy support, software companies can delay updating their applications, knowing that they will still run, albeit without the latest and greatest features. In this case, the latest and greatest feature is correct line widths. To be fair to Vectorworks, depending upon the level of change to the libraries, updating to modern libraries may take considerable effort on behalf of the software company, involving not just rewriting, but potentially moving to an entirely new development platform (similar to an office changing drafting software). So while I can understand Vectorworks running a little behind, the should not be years behind for such a critical issue.

In addition, system software often lags the latest software tricks, and software companies often "roll their own" routines to achieve what the operating system cannot. Vectorworks should have done this with their angled line drawing routines from the beginning.

To be fair to Apple, this problem doesn't show up on the Mac except in Vectorworks, or other QuickDraw dependent programs. (MacDraw or Claris Draw anyone?) As highlighted above, the angle line weight problem doesn't show up on the Mac for any software that has been written to use Apple's more current libraries.

The fat diagonal lines no longer appearing on your old PC version of Vectorworks sounds like MS rewriting their libraries, or you might not have "Zoom Line Thickness" turned on in the preferences. Unless Vectorworks just doesn't like their Mac cousins anymore.

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On one of the links here, or a link from one of them, I remember reading that ClarisDraw has the same problem with fat diagonal lines.

VW lines on the PC have round ends, but they always did, even when the diagonal lines were fat.

I always use Zoom Line Thickness.

Losing the fat diagonals on the PC can't be something Nemetschek did, because I remember fat diagonals from a time when version 9 or 10 was already out, and now even version 8 doesn't have them. That's why I thought it was "very interesting".

Unless I'm losing my mind, and remembering something that never really happened. Can anyone confirm this, that diagonal lines used to be fatter on the PC screen? Or provide other evidence that I'm losing my mind?

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Thanks for the VW history.

ClarisDraw does/did have the problem with fat diagonal. Just like VW, it uses QuickDraw and sqaure pen tips. But ClarisDraw was last updated in about '93.

The fat pen with round tips sound strange. The round cap could have been added after the line was drawn using a square pen, but that sounds unlikely.

Sorry, but I am out of my depth on PC issues.

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As a workaround you might want to try this one out.

In OSX 10.4.2 set up a new IP printer using a random IP address (111.111.1.1 for example). Choose the HP 3500 CP PS3 driver as your printer.

Then When you go to print in VW select save as post script in the Save as pdf menu.

This will then create a PS file which you can then open in OSX preview and save as a PDF. It draws the lines with a round pen so it eliminates the thicker diagonal lines. Not ideal I know but it seems to work. The only problem is that it doesn't seem to embed all fonts (helvetica works fine).

Give it a go.

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Thanks Barry.

I'll try it, and report back.

I used to have an old MG, that I could never get into 1st gear unless I put it in 2nd gear before trying to get it into 1st gear. I think the synchromesh was broken. It wasn't that I couldn't drive the car, it was just a extra step I had to take to use the car as designed. The car was old and its idiosyncratic gear-shift was charming.

I am ranting because it seems to me that I shouldn't have to do a similar dance to get Vectroworks (which by the way, cost more than the MG) to print as expected. There are reports on the boards of users writing scripts to adjust the line width so that printout look correct.

Why do we have to take a two-step just to print a plot? Isn't printing/plotting a fundamental property of a CAD program?

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Thanks Barry.

I tried exactly as you suggested, but it is no better. Different, but no better.

Yes, the pen is rotated on some of the angled lines, but not all of them. Why on some, I cannot begin to guess. When a line is rotated, the intersection between the two angled lines shows a gap on the outside off the angle.

The curves are still crapulent, varying in line thickness and position, due to what I assume is VW still using deprecated integer plotting routines.

On round-cornered rectangles, VW creates polygons for the rounded corners, but uses fat lines for the straight parts. Needless to say, the pen thickness for the straight lines and the VW-calculated polygons is not consistent.

We regard our drawings to be both functional and artistic, portraying the same craftsmanship that our hard line sets used to. When a contractor sees a beautiful drawing, not only is the design clear, but it helps him understand the quality of the craftsmanship expected. Conversely, when he see a set with widely varying line weights, not only is it difficult to read, but it conveys an unintended acceptance of sloppiness.

If anyone else has this problem and/or a fix, I'd be very grateful.

Katie, when you get back from your August break, will you say when this will be fixed?

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altoids,

I couldn't agree with you more. Your comparisons are humorous and right on. I've been pulling out my hair for years due to vectorworks line thickness inconsistencies. I love most aspects of Vectorworks- the simplicity, intuitive drafting UI, and neutral interface. And unlike other CAD programs, there is no complicated method of printing. It prints what you see. What a concept. (autocad users will know what i'm talking about)

The line thickness issue is the main reason keeping me from upgrading to new versions of Vectorworks. In fact, we've been trying out other software and the first thing we confirm is the print line quality. As you mentioned, Architects are very visual, and precision prints are the most important products of our work.

Nametschek, Please step up and resolve this issue!

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Would someone from Nemetschek Tech Suport like to weigh in on this very legitimate, persistent and annoying issue? I've had to live with this problem also, most recently in printing to a HP488ca from a Mac mini w/ OSX 10.4.2. It really messes up some otherwise nice drawings and is noticed by my contractors and clients as well. Is it really that hard to fix or such a low priority?

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The printing issue with thick lines is directly linked to VW 11 being a carbonized application and that technology. The alleviate the problem, checkmark Rasterize Print Output in the Print dialog box under the VectorWorks section.

With that said, VectorWorks 12 is now a quartz application, dropping OS 9, so as to not have the thick lines problem. This is only one of the many benefits of being a true Quartz application.

Some of the other benefits of Quartz include the ability to export directly to PDF, true transparency (yes, on PC too!), true line thickness on the screen and prints (because of the ability to draw and print with a round pen), and many more.

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