Polygons as Subdivision - Distorted Textures

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Hi all,

I am rendering an object with Polygons as Subdivisions ON (at OBJ level) but my textures are getting all distorted. When I have Polygons as Subdivisions OFF, it renders fine.

I have the object divided into 2 Groups. Each Group has different UVs and a different material applied to it (SOP level).

I have tried applying materials at OBJ level, but I can't apply more than one material at this level.

Is there a way to apply more than one material at OBJ level?

How can I avoid my textures getting distorted with Polygons as Subdivisions ON ?

Thanks in advance
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Do you have a file you can share?
Francisco Rodriguez
Effects Animator | Walt Disney Animation Studios
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Made a simpler scene with a tube to illustrate the problem. Taken the Groups out and just using a UVQuickshade SOP.

But still gettting distorted textures when Polys as Subdivs is on.

It could be a stupid question, I think I'm missing something out in here

Attachments:
subdiv_test.hipnc (247.5 KB)
subdic_on.jpg (76.9 KB)
subdic_off.jpg (82.2 KB)

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Under Houdini 10 there was the layered texture material (accessable under shops). There you could have more textures on one material with different uv-sets. I used this material quite often, now it seems to be gone and I miss it dearly.

I heard that it is still there but not visible because of the new shader system. Anyone knows how to dig it out or how to layer textures now.

Lutze
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Looks like you're starting with a fairly low number of non-convex polys. The Subdivide SOP uses a Catmul-Clark subdivision algorithm which tries to “smooth” the geometry as it subdivides. Since your geometry is fairly sparse, it tries to smooth over non-optimal polys.

From the help:
While the topology of the input mesh can be arbitrary, for best results all polygons should be convex and relatively uniform in distribution.

So, since capping the tube doesn't give you the isoparms you need, I went ahead and used a poly-extrude on the top and bottom caps to inset them. This is a good way to quickly give you quads, since you want to use as few triangles as possible. This will help the algorithm out and you'll be able to get decent subd's.

Attachments:
subdivTestH11.hipnc (232.8 KB)

Francisco Rodriguez
Effects Animator | Walt Disney Animation Studios
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