38 lines
1.7 KiB
GLSL
38 lines
1.7 KiB
GLSL
// From "An Efficient Representation for Irradiance Environment Maps" article
|
|
// See http://graphics.stanford.edu/papers/envmap/
|
|
// Coefficients are calculated in IBL.cpp
|
|
|
|
mat4 getMatrix(float L00, float L1m1, float L10, float L11, float L2m2, float L2m1, float L20, float L21, float L22)
|
|
{
|
|
float c1 = 0.429043, c2 = 0.511664, c3 = 0.743125, c4 = 0.886227, c5 = 0.247708;
|
|
|
|
return mat4(
|
|
c1 * L22, c1 * L2m2, c1 * L21, c2 * L11,
|
|
c1 * L2m2, - c1 * L22, c1 * L2m1, c2 * L1m1,
|
|
c1 * L21, c1 * L2m1, c3 * L20, c2 * L10,
|
|
c2 * L11, c2 * L1m1, c2 * L10, c4 * L00 - c5 * L20
|
|
);
|
|
}
|
|
|
|
vec3 DiffuseIBL(vec3 normal)
|
|
{
|
|
// Convert normal in wobLd space (where SH coordinates were computed)
|
|
vec4 extendednormal = transpose(u_view_matrix) * vec4(normal, 0.);
|
|
extendednormal.w = 1.;
|
|
|
|
#ifdef UBO_DISABLED
|
|
mat4 rmat = getMatrix(redLmn[0], redLmn[1], redLmn[2], redLmn[3], redLmn[4], redLmn[5], redLmn[6], redLmn[7], redLmn[8]);
|
|
mat4 gmat = getMatrix(greenLmn[0], greenLmn[1], greenLmn[2], greenLmn[3], greenLmn[4], greenLmn[5], greenLmn[6], greenLmn[7], greenLmn[8]);
|
|
mat4 bmat = getMatrix(blueLmn[0], blueLmn[1], blueLmn[2], blueLmn[3], blueLmn[4], blueLmn[5], blueLmn[6], blueLmn[7], blueLmn[8]);
|
|
#else
|
|
mat4 rmat = getMatrix(rL00, rL1m1, rL10, rL11, rL2m2, rL2m1, rL20, rL21, rL22);
|
|
mat4 gmat = getMatrix(gL00, gL1m1, gL10, gL11, gL2m2, gL2m1, gL20, gL21, gL22);
|
|
mat4 bmat = getMatrix(bL00, bL1m1, bL10, bL11, bL2m2, bL2m1, bL20, bL21, bL22);
|
|
#endif
|
|
|
|
float r = dot(extendednormal, rmat * extendednormal);
|
|
float g = dot(extendednormal, gmat * extendednormal);
|
|
float b = dot(extendednormal, bmat * extendednormal);
|
|
|
|
return max(vec3(r, g, b), vec3(0.));
|
|
} |