I have a face I’m UV mapping. The face has four corners, and all four vertices are co-planar. The face is mostly rectangular, but one side is slightly shorter than the other (many of these faces combine to form a ring, so the inside of the “circle” is necessarily shorter than the outside). Because I’m mapping the face to floor tiles, the seam between faces is very noticeable if I project the face onto the UV map.
So the plan was to simply stretch the UV map a little, so each floor tile would be slightly distorted, but the face could be mapped to an integer number of floor tiles, and the seam would seem natural.
The problem is the face is rendering as two separate triangles with independent UV mapping, instead of a single quad face. I’ve tried converting tris to quad, but it seems to still UV map as tris.
Is there any way to UV map a quad so the texture location is determined by the distance to all four points, instead of just three points?
Here’s an example of a UV map that’s skewed. Clearly, we’d expect some distortion, but it’s not a complex shape.
Here’s the quad I’m trying to map to. We can clearly see the left half of the quad is being mapped as one triangle, while the right half is a second triangle. (The screenshot has a mapping node, so the mapping is being repeated. But setting the scale back to 1 so it’s a direct mapping gives the same skewed result.)
Because the two triangles are skewed, the image is skewed. What I’d like to see is a mapping where straight lines across the quad are mapped to straight lines on the texture. Something like this: the four corners (purple) obviously map to the corners. Points about 25% from the bottom (red) would map across the texture proportionally, near the bottom, and points about 2/3rds up (blue) would likewise map across a different line on the texture.
Is there a way to what I’m wanting? I feel like this is probably stupidly obvious, but I’m not understanding what to call this so I can properly search for it.
