Breaking up Single grid with texture atlas applied

[art3mis]

Hi

Perhaps this is the wrong approach in working with texture Atlases in Houdini. The only tutorial I could find was Modo specific.

I need to use high resolution texture atlases to create my materials in Houdini.

So I have taken a texture  atlas with various maps, roughness, albedo, etc and created my material.

I have then created a 1 unit grid, added a UVtexture SOP and then applied this material.

So far so good.

In my case the texture Atlas contains a dozen different leaves.

No how do I 'break up' this single grid geometry so I can isolate and transform each leaf separately?

 

 

[Atom]

Drop down a UVTexture node, following the grid. Then follow that up with a UVTransform. The goal, I assume, is one leaf per grid? Use the UVTransform controls to scale and offset the atlas so only a single leaf fills the entire grid. Then duplicate that 3-node setup and offset to dial in the other leaves etc...

 

In general, I don't really like the texture atlas approach. I'd rather have a single matching image set for each entry in the atlas instead. The approach I took is to "fix" the textures before I get to Houdini rather than to create elaborate node setups to deal with massive offset and scaling. I created an After Effects scene to process each of the elements I wanted out of the atlas and saved them out as their own plant image set.

 

Edited June 28, 2017 by Atom

[art3mis]

Thanks Atom. Breaking up the atlas first as you suggest sounds like it might be the best approach in Houdini.

Perhaps in combination with using the Trace SOP to create the geometry.

Not the quickest of workflows however:(

[art3mis]

Took the single image approach along with the Trace Outline SOP. Not sure if using the Sprite Stencil shader might be better for defining the outline. Need collision.