Getting UVs from Polygon

[drehwurm]

Hi everybody,

I’m using the Triangle-Contribution to create a polygon-mesh. Now I would like to map a Texture to it, and there I’m a bit stuck. I don’t get how to convert from object-space to texture space. I know the differences, but the math is giving me a little headache. I appreciate any hint.

thanks

triangle_Polygon.zip (10.9 KB)

[h99]

I can’t get it to work, it’s pink AF.
Rereading it, the math is that vertex coords lie in -1[…]1, tex coords in 0[…]1, also dx tex start from upper left, and propagates to opposite corner.

If you want to map a 2*2 grid of Scale 1 (vertices at +/-0.5) you’ll simply take those vertices and map them into a 0[…]1 interval. So the top left corner (vertex coords: -0.5,0.5) will have 0.0,0.0 tex coords. The vertex at -0.5,0.0 will have 0.0,0.5. The bottom left vertex at 0.5,-0.5 will have 1.0,1.0; so you see it’s a 0.0[…]1.0.

This would work in dx9; don’t know in 11, but it shouldn’t be too different.

[drehwurm]

Crazy… which nodes don’t work?

[h99]

Triangle

Edit: It’s a pack!

Reedit: Add a iid and a uv_coords between indexedgeometrybuffer and constant.fx
and in InputElement put also normals (format as the position) between position and texturecoord