How to do the shadow mapping after perspective deformations? about tinyrenderer HOT 1 OPEN

I fixed this problem by passing both "bc_screen" and "bc_clip" into the fragment shader.

In the triangle() of our_gl.cpp, I store the pts2.z as the fragment_depth instead of pts.z so that I can make sure that the z-value and the x-value & y-value in idx (x+y*width) come from the same point, P'. Now we make the index of the shadowBuffer in this pixel and the z-value of in this pixel consistent.

In the DepthShader, I did almost the same thing as in Lesson 7 (but I tried to save the vertices after MVP into the varying_tri instead of the vertices after VP, while the vertex shader still returned the vertices after VP transformation to the main function).

Then in the Shader, I used "bc_screen" and varying_tri (still, it saved the vertices after MVP) to calculate the (x', y', z') of P'。 And use the (x', y') to get the index to access the shadowBuffer, and compared it with z'。After that, I used "bc_clip" to do whatever we should do to calculate uv, n, and other stuff.

from tinyrenderer.