1 #define SCALE 0.12 2 #define BIAS -0.04 3 #define BIN_ITER 5 4 5 #ifndef BUMP_HQ 6 #define LIN_ITER 5 7 #endif 8 9 vec2 Bump_DoOcclusionParallax(in sampler2D heightMap, in vec2 texCoord, in vec3 tanViewDir){ 10 float size = 1.0 / float(BIN_ITER); 11 12 // depth 13 float d = 1.0; 14 // best depth 15 float bd = 0.0; 16 17 #ifdef BUMP_HQ 18 const int N = 8; 19 int LIN_ITER = mix(2 * N, N, tanViewDir.z); 20 #endif 21 22 // search from front to back 23 for (int i = 0; i < LIN_ITER; i++){ 24 d -= dstep; 25 float h = texture2D(heightMap, dp + ds * (1.0 - d)).a; 26 if (bd < 0.005) // if no depth found yet 27 if (d <= h) bd = depth; // best depth 28 } 29 30 for (int i = 0; i < BIN_ITER; i++) { 31 size *= 0.5; 32 float t = texture2D(heightMap, dp + ds * (1.0 - d)).a; 33 if (d <= t) { 34 bd = depth; 35 d += 2 * size; 36 } 37 d -= size; 38 } 39 } 40 41 vec2 Bump_DoParallax(in sampler2D heightMap, in vec2 texCoord, in vec3 tanViewDir){ 42 float h = texture2D(heightMap, texCoord).a * SCALE + BIAS; 43 return texCoord + h * tanViewDir.xy; 44 }
