Cat Harris

Hi all, I'm trying to work out if it's possible to take geo with existing shaders and then add additional aov shader passes without having to do multiple renders. For workflow reasons we'd really like to just have one exr output with beauty and all AOVs included.

simple example - I'd like to take an prebuilt usd asset and render it with both its original correct shaders (beauty, reflections etc.) and also add a custom uvmap pass.

Things I've already tried:

• Creating the custom aov shader separately in the material library - works fine if I'm happy to render this separately but I can't find a way to switch between the beauty and aov shaders within the same render
  
• Doing everything with primvars - works fine for attrib based AOVs, but some things eg. texture maps only work if I go via a shader.
  
• Using an edit material to add the map and a Karma AOV to a shader, then outputting everything either as binds or using the Subnet Outputs node - this seems to add the attribs to the material prim that I'd expect, but still renders black even when the made-from-scratch AOV shader is working on other geo.
  
• Trying to do it in python - I'm not sure what I'm missing in terms of USD structure and changes to the mtlx shader prims to make this all work, so this ran aground pretty quickly in the API docs!
  

Hopefully someone's already had a play with this and has a solution, if not I'd love to know if anyone has any more ideas I can try!

Hi, I'm having a go at working with the HDK, but I can't get the geoisosurface.C file to compile properly as explained in the introduction documentation.

When I run hcustom -s geoisosurface.C

The geoisosurface.o file seems to be generated correctly, but then I get the error

ld: file not found: @rpath/libHoudiniAPPS3.dylib for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Link failed

The clang command that's being run (found via running hcustom with -se flags) is

/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ geoisosurface.o -o ./geoisosurface -Wl,-rpath,/Library/Frameworks/Houdini.framework/Versions/15.0.416/Libraries -L/Library/Frameworks/Houdini.framework/Versions/15.0.416/Libraries /Library/Frameworks/Houdini.framework/Versions/15.0.416/Houdini -arch x86_64 -fobjc-gc -framework OpenGL -framework Cocoa

I've checked and the file libHoudiniAPPS3.dylib does exist in /Library/Frameworks/Houdini.framework/Versions/15.0.416/Libraries.

I'm running El Capitan 10.11.4 and have the latest version of Xcode (v7.3), and have a clean install of Houdini v15.0.416.

Sadly I've now reached my limit of debugging skills, so is there anyone who knows what's up here? Have I just not set something up correctly, or should I submit a bug to SESI?

I'm not sure if this solves what you're asking, but an agent in a crowd won't have primitive groups available because it's packed.

If you create a quick very small test crowd and then unpack it, do you see your groups then?

If that's working then in order to apply group-based shading to packed stuff you need to use the material stylesheets, which are a little messy in 14.0, but the docs and some examples live here: http://www.sidefx.com/docs/houdini14.0/shade/stylesheets [sidefx.com]