Per instance UV Mapping

uv-mapping
instancing
textures

#1

Ok, so I have an InstancedBufferGeometry using a plane geometry as the geometry to be instanced and I am instantiating it 256 times in different positions. I am also applying a 256x256 image texture as the material map which is succesfully being applied to all the instances.

However, what I would actually like to do is have only different sections of the texture being applied to each instance rather than the standard 0,0 - 1,1 uv map being applied to all instances.

At the moment, I have tried passing in a vector4 per instance defining the desired top left and bottom right uv-co-ordinates per instance, then in the shader I check if the uv parameters are either 0 or 1 and change them accordingly to the equivalents that i put into the vector4. But this doesn’t seem to work very well.

Any idea as to how I could do this better?
Your help would be appreciated.


#2

From what you describe it sounds the right way, using a InstancedBufferAttribute for the InstancedBufferGeometry. You probably should provide code or a fiddle. It can be everything, missing needsUpdate on the attributes, issues in the shader code etc.


#3

Hey I’m trying to do a similar thing and I’m a bit stuck also… did you figure it out in the end? Would love some tips!