SOPs: how to unroll a curved plane into a flat rectangle

I need to unroll this sort of shape into a rectangle. The shape has custom UVs assigned. Is there a SOP that could help?

Hey @dancing_pixels,

is it your aim to get to the UVs as a texture?

In this case you could use the Render TOP’s “UV Unwrap” Render Mode parameter setting. This will unwrap texture coordinates of a specific texture layer. Now to display them, you would have to create a Phong MAT and on the Advanced page of the parameters select the correct Texture Coord Layer for the Color Buffer 1 RGB parameter. This essentially will render the UV Textures into a second Color Buffer of the Render TOP.

To finalize this, on the “Advanced” page of the Render TOP, set the # of Color Buffers parameter to 2 and create a Render Select TOP where you set the Color Buffer Index to 1.

Now - that’s a bit a lot of steps, I’ve attached a simple example :slight_smile:

uvUnwrapping.tox (12.1 KB)

I’m trying to do something similar but even with your advices I can’t make it works… I have an assemblage of cubes and I wish to get the uv unwrapped. I tried to do it directly inside touchdesigner or by importing an external obj / fbx like you did in your example, but when I link it to the geo it only gives me the UV map of a single cube, I really don’t get it.
I must be doing something wrong, could you try to help me?

I attached your example with my cubes :slight_smile:

Thanks a lot!

uvUnwrapping-cubes.1.toe (780.3 KB)

Hey @pablofelley,

this is pretty much expected as all cubes occupy the same texture coordinates. Per texture coordinate layer you only have the normalized space (0-1) available to you so all of them overlap.

In the attached file I’ve added a texture SOP to each box and set the “Texture Type” parameter to Modify Source. Then I scaled down the texture coordinates for each cube and offset them a bit. The output now shows 4 seperate sections that each cube grabs it’s texture from.

Hope this helps
uvUnwrapping-cubes.2.toe (4.8 KB)

Oooh thanks a lot that explains a lot!!
Now I get it :slight_smile: