Slow rendering

[RBKarcht]

I am a beginner with RenderWorks, but not with 3D modeling and animation. While I like the RenderWorks/VectorWorks package, I have been experiencing a problem with rendering on a PM G4 with 320 MB of RAM. Even when the quality settings are set low (1 ray bounce, shadows are not ray traced, etc.), generating a rendering is much slower than what we have become used to with competing software packages (also using Ray Tracing). I have played around with the memory allocation (setting the VW allocation as low as possible) and that does not seem to make much difference.

Also, the Render Bitmap tool has been rather fussy and won't work (it just shows white space when where I have drawn a marquee).

What am I missing?

[Hannes]

Also, the Render Bitmap tool has been rather fussy and won't work (it just shows white space when where I have drawn a marquee).

AFAIK this is a known bug.

Be sure that the screen pixel ratio setting at the document preferences is set to 1:1.

[Guest]

In addition to setting your screen ratio to 1:1, you should know that the "furriness", uh I mean "fuzziness" of the output from the render bitmap tool is a result of the resolution setting for the tool itself, and your zoom factor. The Render Bitmap tool has it's own settings for rendering resolution. I use 72dpi or less to determine lighting, and bump it up to 300dpi or more to do final renderings.

However, sometimes rendering at 600 dpi, when zoomed way in, your image may still appear fuzzy. In actuality, if you print or copy and paste this same image into a bitmap editor, you'll see that it is really sharp. This is because the Render Bitmap tool renders a specific set of pixels regardless of your zoom factor, based on your page size. Just like if you import a raster file into a VectorWorks document and zoom in, it will get fuzzy.

For example, if you have a 24" X 36" sheet, and you marquee an area that is half that, 24" X 18", at 72 dpi, you will render 31,104 dots. That will produce an image 5.76" x 4.32" at 300dpi. If you render half of an 8.5 x 11" sheet at 72dpi, you will render 3,366 producing an image that's only 1.32" x 2.04" at 300dpi. In the first instance I'm probably fine at 72dpi. In the second instance I'd have to bump the Render Bitmap resolution to more the 660dpi to create a comparable image for my brochure or other print medium. For the web I can get away with much less.

This can be useful, because you can always render the same set of pixels no matter how you are zoomed. If you zoom way in on a tiny component and render at 72dpi, it is the same as if you were zoomed way out and rendered. If you zoom way in and render using the menu command, it will render the entire screen, all 1000 X 1000 pixels or so (1,000,000 dots), slowing you way down, despite the fact that you are rendering a tiny component. When you add in that fact that your rendering isn't saved when using the menu command, the Render Bitmap tool seems even more virtuous.

If this rather long response hasn't completely confused you, then I think you'll find the Render Bitmap tool to be very useful.

p.s. The short answer is that the RayMaker raytracer is not as fast as some of the competition. We are working on the speed, but in the meantime...

1. Using the Render Bitmap tool

2. Use the interactive renderer when you're modeling

3. Keep the polygon count low

4. Make objects that will not be seen in the rendering invisible via classes

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-- Michael Pacylowski --

[broesler]

Just a few words regarding Renderworks and various settings. I produce ray-traced thousand-color shadow renderings of hotel building(s) on a regular basis as part of both my design and presentation work flow. Using a Mac 450mh G3, VW 8.5.1, 256mb real RAM and maximum virtual RAM, I find I can usually render an image that will print without pixalation at 720dpi with my VW RAM allocation set to 175mb. This allows me 50mb to run something else simultaneously if necessary, though I try to avoid that. Using Renderworks bit-map tool, I end up with 30mb? pict images I can cut and paste into a manageable-size file. My clients are impressed and my billing rate shows it. I have played with all of the settings extensively, and find the only one that affects what I am interested in (the rendered bit-map image) is the resolution dialog box accessible by clicking the right-most icon on the tool bar (I probably have the name of that wrong). There you can set the point-per-inch/pixel-per-inch/dots-per-inch, whatever you want to call it - there you set the "resolution" of the area you enclose with the bit-map tool marquee. My normal print-out paper size is A2 (on an Epson 1520) trimmed to 13.5" x 22" (printer's maximum print). When I set my perspective view and close the bounding marquee as tight as practical, the image area is usually somewhere around 1/4 -1/3 the printable area of the A2 size paper. I am usually able to render this with a resolution of 150-250, within 10-15 minutes, producing a pict file I must cut/copy and paste into a separate document to maintain file reasonable file size. Even with 256mb of real RAM, I have only enough RAM to combine 3 rendereded images in a single file (84mb?) and open Epson Printmonitor after playing with the RAM settings. Like they always say, there's no substitute for REAL RAM. VW with RW module is a great application. My business depends on it. I'm looking forward to a Mac G4, OS X, and VW 9 with Velocity-engine. Hip - Hip - Hooray!

[Guest]

broesler, it sounds like you really know what you're doing. I'm glad you have all the tools working for you. If you have any images that you're particularly prod of, I'd be happy to add it to the gallery pages on the web site, and include it in other marketing materials like ads and brochures.

If you have a moment, e-mail some small jpgs as examples.

mikep@diehlgraphsoft.com

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-- Michael Pacylowski --

[MikeB]

broesler

What size (in inches) do you print your final images? I have also played with the settings and the best I can get is to set my perspective marque to an E size sheet and export the image at 72 dpi (if I change the dpi in the export dialoge I just get a smaller image in inches with the same # of pixels, If I increase the # of pixels VW crashes). Then in Photoshop I Have an image that is approx. 44" wide and 72 dpi. I can reduce this to approx 22" at 150 dpi with no loss of clarity and they print beautifully at the full width of 22", the problem is it can take several (up to 12 ) hours to export depending on the amount of transparency and reflectivity. I'm going to try your settings to see the difference.

I also use a G4 400 and I'm very excited about VW9 as well.

Michael

Do you know if Renderworks capability will be greatly expanded in the next version or not?

Just wondering. Renderworks is really great especially for the first release, I just hope Diehlgraphsoft will build it up.

Thanks

[Guest]

I can not give any details or make any promises about the next version. The only thing I can say is that I looks to be a very robust upgrade, delivering on several wish list items, I think, maybe, don't quote me, probably, well I'm 50% sure.

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-- Michael Pacylowski --