Rebar Models will not render

Discussions about the development of the TechDraw workbench
elsordo
Posts: 52
Joined: Sat Jan 30, 2016 6:34 am

Re: Rebar Models will not render

Postby elsordo » Sat Jul 25, 2020 3:45 pm

Thanks for the feed back.

So, it looks like that rendering rebar is still a performance problem in the absence of geometry errors.

Is this correct?

-David
User avatar
wandererfan
Posts: 4078
Joined: Tue Nov 06, 2012 5:42 pm

Re: Rebar Models will not render

Postby wandererfan » Sun Jul 26, 2020 2:05 pm

elsordo wrote:
Sat Jul 25, 2020 3:45 pm
So, it looks like that rendering rebar is still a performance problem in the absence of geometry errors.
I'd have to see a rebar model without geometry errors to confirm this. I suspect any model with 25,000 shapes is going to be slow.

The rebar model is rather like an assembly. In order to create an accurate depiction we must consider the assembly, not the components. If the assembly has geometry errors, then OCC will take much longer to process it.

It might be possible to make a special view for models like this where each shape is drawn separately. Hidden line functionality would be lost. Determining the stacking order of each shape would be tricky and any faces involved would have to be opaque. This would effectively be an implementation of the "painter's algorithm", but without the convenience of a mesh.