Returning a given texture coord in 3d space

is there a way of finding out a where in 3d space a point on a texture is?

for example, say i have an object with a texture loaded into texture layer 1. How could i find out the x,y,z coords of every pixel in the texture?

ie
for x= 0 to texturewidth(blah)-1
for y= 0 to texturewidth(blah)-1
.
.
somehow find out the x,y,z of each point
.
.
next
next

I think there's something in the code archives that does that with vertices.

Well supposing textures are on triangles, you can access vertex data and interpolate to go trhough the triangle...

Or at least i think so...