Tracing/Extruding HighRes Images very slow

[Fele]

Hello,

I am modeling a lot of different shapes from elevation maps which are essentially just black and white images. I tried tracing and extruding them but as soon the resolution gehts above ~500px its almost impossible to handle. I think the main problem are the inside shapes like seas/rivers which of course get subtracted. Images with about 2000px or more are almost impossible to extrude and very hard to handle. Is there way to simplify or speed up this process?

Thanks

Felix

 

[acey195]

extrusion is a quite slow operation if done on a large amount of geometry, tracing should relatively fast I think.
you probably want to optimize your mesh right after the tracing I think, with a Remesh/PolyReduce Node.

[f1480187]

I think it is because of a small sample step and, in result, enormous amount of points created. Turn on Resample Shapes toggle on Trace node and set Step Size to relatively large number, like 50. I think this is a distance in pixels, definitely not in Houdini units. It will dramatically improve performance. Butterfly pic scaled to 4096 cooks for a 1 second.

trace.hipnc

Edited June 28, 2016 by f1480187

[Fele]

Thanks guys. It was indeed the point count wich I reduced a lot by the trace resampling parameter. Lead to much better results than the facet and resample. Overall I figured its because of the small "islands" inside the surface which get subtracted during the extrusion. Without those its super fast..

Edited June 28, 2016 by Fele