Collision Detection on a Plane based on color

Target Platforms Mobile
1

I have a “sprite” Plane that is white with a red circle as part of the material.
Is there a way to determine the color of a mesh surface at a point on the surface?

I am hoping to achieve some sort of quick and dirty collision detection (similar to using a getPixels call in flash)

2

You can do this using a raycast. The RaycastHit object returned by the function has a texture coordinate field. You can pass the coordinates to the Texture2D.GetPixelBilinear and check the colour primaries to see if they are close to the target value.