mirror of
https://gitlab.com/veloren/veloren.git
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620 lines
26 KiB
GLSL
620 lines
26 KiB
GLSL
// Linear RGB, attenuation coefficients for water at roughly R, G, B wavelengths.
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// See https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_water
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const vec3 MU_WATER = vec3(0.6, 0.04, 0.01);
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// // NOTE: Automatic in v4.0
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// float
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// mip_map_level(in vec2 texture_coordinate)
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// {
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// // The OpenGL Graphics System: A Specification 4.2
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// // - chapter 3.9.11, equation 3.21
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//
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//
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// vec2 dx_vtc = dFdx(texture_coordinate);
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// vec2 dy_vtc = dFdy(texture_coordinate);
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// float delta_max_sqr = max(dot(dx_vtc, dx_vtc), dot(dy_vtc, dy_vtc));
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//
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//
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// //return max(0.0, 0.5 * log2(delta_max_sqr) - 1.0); // == log2(sqrt(delta_max_sqr));
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// return 0.5 * log2(delta_max_sqr); // == log2(sqrt(delta_max_sqr));
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// }
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//https://gamedev.stackexchange.com/questions/92015/optimized-linear-to-srgb-glsl
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vec3 srgb_to_linear(vec3 srgb) {
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bvec3 cutoff = lessThan(srgb, vec3(0.04045));
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vec3 higher = pow((srgb + vec3(0.055))/vec3(1.055), vec3(2.4));
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vec3 lower = srgb/vec3(12.92);
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return mix(higher, lower, cutoff);
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}
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vec3 linear_to_srgb(vec3 col) {
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// bvec3 cutoff = lessThan(col, vec3(0.0060));
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// return mix(11.500726 * col, , cutoff);
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vec3 s1 = vec3(sqrt(col.r), sqrt(col.g), sqrt(col.b));
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vec3 s2 = vec3(sqrt(s1.r), sqrt(s1.g), sqrt(s1.b));
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vec3 s3 = vec3(sqrt(s2.r), sqrt(s2.g), sqrt(s2.b));
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return vec3(
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mix(11.500726 * col.r, (0.585122381 * s1.r + 0.783140355 * s2.r - 0.368262736 * s3.r), clamp((col.r - 0.0060) * 10000.0, 0.0, 1.0)),
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mix(11.500726 * col.g, (0.585122381 * s1.g + 0.783140355 * s2.g - 0.368262736 * s3.g), clamp((col.g - 0.0060) * 10000.0, 0.0, 1.0)),
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mix(11.500726 * col.b, (0.585122381 * s1.b + 0.783140355 * s2.b - 0.368262736 * s3.b), clamp((col.b - 0.0060) * 10000.0, 0.0, 1.0))
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);
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}
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float pow5(float x) {
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float x2 = x * x;
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return x2 * x2 * x;
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}
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vec4 pow5(vec4 x) {
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vec4 x2 = x * x;
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return x2 * x2 * x;
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}
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// Fresnel angle for perfectly specular dialectric materials.
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// Schlick approximation
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vec3 schlick_fresnel(vec3 Rs, float cosTheta) {
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// auto pow5 = [](Float v) { return (v * v) * (v * v) * v; };
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// return Rs + pow5(1 - cosTheta) * (Spectrum(1.) - Rs);
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return Rs + pow5(1.0 - cosTheta) * (1.0 - Rs);
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}
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// Beckmann Distribution
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float BeckmannDistribution_D(float NdotH, float alpha) {
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const float PI = 3.1415926535897932384626433832795;
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float NdotH2 = NdotH * NdotH;
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float NdotH2m2 = NdotH2 * alpha * alpha;
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float k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
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return mix(k_spec, 0.0, NdotH == 0.0);
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}
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// Voxel Distribution
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float BeckmannDistribution_D_Voxel(vec3 wh, vec3 voxel_norm, float alpha) {
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vec3 sides = sign(voxel_norm);
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// vec3 cos_sides_i = /*sides * */sides * norm;
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// vec3 cos_sides_o = max(sides * view_dir, 0.0);
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vec3 NdotH = wh * sides;//max(wh * sides, 0.0);/*cos_sides_i*///max(sides * wh, 0.0);
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const float PI = 3.1415926535897932384626433832795;
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vec3 NdotH2 = NdotH * NdotH;
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vec3 NdotH2m2 = NdotH2 * alpha * alpha;
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vec3 k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
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return dot(mix(k_spec, /*cos_sides_o*/vec3(0.0), equal(NdotH, vec3(0.0))), /*cos_sides_i*/abs(voxel_norm));
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// // const float PI = 3.1415926535897932384626433832795;
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// const vec3 normals[6] = vec3[](vec3(1,0,0), vec3(0,1,0), vec3(0,0,1), vec3(-1,0,0), vec3(0,-1,0), vec3(0,0,-1));
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// float voxel_norm = 0.0;
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// for (int i = 0; i < 6; i ++) {
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// // Light reflecting off the half-angle can shine on up to three sides.
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// // So, the idea here is to figure out the ratio of visibility of each of these
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// // three sides such that their sum adds to 1, then computing a Beckmann Distribution for each side times
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// // the this ratio.
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// //
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// // The ratio of these normals in each direction should be the sum of their cosines with the light over π,
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// // I think.
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// //
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// // cos (wh, theta)
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// //
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// // - one normal
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// //
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// // The ratio of each of the three exposed sides should just be the slope.
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// vec3 side = normals[i];
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// float side_share = max(dot(norm, side), 0.0);
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// float NdotH = max(dot(wh, side), 0.0);
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// voxel_norm += side_share * BeckmannDistribution_D(NdotH, alpha);
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// // voxel_norm += normals[i] * side_visible * max(dot(-cam_dir, normals[i]), 0.0);
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// // voxel_norm += normals[i] * side_visible * max(dot(-cam_dir, normals[i]), 0.0);
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// }
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// /* float NdotH = dot(wh, norm);
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// float NdotH2 = NdotH * NdotH;
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// float NdotH2m2 = NdotH2 * alpha * alpha;
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// float k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
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// return mix(k_spec, 0.0, NdotH == 0.0); */
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// return voxel_norm;
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}
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float TrowbridgeReitzDistribution_D_Voxel(vec3 wh, vec3 voxel_norm, float alpha) {
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vec3 sides = sign(voxel_norm);
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// vec3 cos_sides_i = /*sides * */sides * norm;
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// vec3 cos_sides_o = max(sides * view_dir, 0.0);
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vec3 NdotH = wh * sides;//max(wh * sides, 0.0);/*cos_sides_i*///max(sides * wh, 0.0);
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const float PI = 3.1415926535897932384626433832795;
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vec3 NdotH2 = NdotH * NdotH;
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// vec3 m2 = alpha * alpha;
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// vec3 NdotH2m2 = NdotH2 * m2;
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vec3 NdotH2m2 = NdotH2 * alpha * alpha;
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// vec3 Tan2Theta = (1 - NdotH2) / NdotH2;
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// vec3 e = (NdotH2 / m2 + (1 - NdotH2) / m2) * Tan2Theta;
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// vec3 e = 1 / m2 * (1 - NdotH2) / NdotH2;
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vec3 e = (1 - NdotH2) / NdotH2m2;
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vec3 k_spec = 1.0 / (PI * NdotH2m2 * NdotH2 * (1 + e) * (1 + e));
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// vec3 k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
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return dot(mix(k_spec, /*cos_sides_o*/vec3(0.0), equal(NdotH, vec3(0.0))), /*cos_sides_i*/abs(voxel_norm));
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}
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float BeckmannDistribution_Lambda(vec3 norm, vec3 dir, float alpha) {
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float CosTheta = /*max(dot(norm, dir), 0.0);*/dot(norm, dir);
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/* if (CosTheta == 0.0) {
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return 0.0;
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}
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float SinTheta = sqrt(1.0 - CosTheta * CosTheta);
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float TanTheta = SinTheta / CosTheta;
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float absTanTheta = abs(TanTheta); */
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// vec3 w = normalize(dir - dot(dir, norm) * (norm));
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// float CosTheta = w.z;
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float SinTheta = sqrt(1.0 - CosTheta * CosTheta);
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float TanTheta = SinTheta / CosTheta;
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float absTanTheta = abs(TanTheta);
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/* if (isinf(absTanTheta)) {
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return 0.0;
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} */
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/* float CosPhi = mix(clamp(projDirNorm.x / sinTheta, -1.0, 1.0), 0.0, sinTheta == 0.0);
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float SinPhi = mix(clamp(projDirNorm.y / sinTheta, -1.0, 1.0), 0.0, sinTheta == 0.0);
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float alpha = sqrt(CosPhi * CosPhi * alphax * alphax + SinPhi * SinPhi * alphay * alphay); */
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// Float absTanTheta = std::abs(TanTheta(w));
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// if (std::isinf(absTanTheta)) return 0.;
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// <<Compute alpha for direction w>>
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// Float alpha = std::sqrt(Cos2Phi(w) * alphax * alphax +
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// Sin2Phi(w) * alphay * alphay);
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float a = 1.0 / (alpha * absTanTheta);
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/* if (a >= 1.6) {
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return 0.0;
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}
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return (1.0 - 1.259 * a + 0.396 * a * a) / (3.535 * a + 2.181 * a * a); */
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return mix(max(0.0, (1.0 - 1.259 * a + 0.396 * a * a) / (3.535 * a + 2.181 * a * a)), 0.0, isinf(absTanTheta) || a >= 1.6);
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// Float a = 1 / (alpha * absTanTheta);
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// if (a >= 1.6f)
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// return 0;
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// return (1 - 1.259f * a + 0.396f * a * a) /
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// (3.535f * a + 2.181f * a * a);
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// return 1 / (1 + Lambda(wo) + Lambda(wi));
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}
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float BeckmannDistribution_G(vec3 norm, vec3 dir, vec3 light_dir, float alpha) {
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// return 1 / (1 + Lambda(wo) + Lambda(wi));
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return 1.0 / (1.0 + BeckmannDistribution_Lambda(norm, dir, alpha) + BeckmannDistribution_Lambda(norm, -light_dir, alpha));
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}
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// Fresnel blending
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//
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// http://www.pbr-book.org/3ed-2018/Reflection_Models/Microfacet_Models.html#fragment-MicrofacetDistributionPublicMethods-2
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// and
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// http://www.pbr-book.org/3ed-2018/Reflection_Models/Fresnel_Incidence_Effects.html
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vec3 FresnelBlend_f(vec3 norm, vec3 dir, vec3 light_dir, vec3 R_d, vec3 R_s, float alpha) {
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const float PI = 3.1415926535897932384626433832795;
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alpha = alpha * sqrt(2.0);
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float cos_wi = /*max(*/dot(-light_dir, norm)/*, 0.0)*/;
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float cos_wo = /*max(*/dot(dir, norm)/*, 0.0)*/;
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vec3 diffuse = (28.0 / (23.0 * PI)) * R_d *
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(1.0 - R_s) *
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(1.0 - pow5(1.0 - 0.5 * abs(cos_wi))) *
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(1.0 - pow5(1.0 - 0.5 * abs(cos_wo)));
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/* Spectrum diffuse = (28.f/(23.f*Pi)) * Rd *
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(Spectrum(1.f) - Rs) *
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(1 - pow5(1 - .5f * AbsCosTheta(wi))) *
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(1 - pow5(1 - .5f * AbsCosTheta(wo))); */
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// Vector3f wh = wi + wo;
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vec3 wh = -light_dir + dir;
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#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
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bool is_blocked = cos_wi == 0.0 || cos_wo == 0.0;
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#else
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bool is_blocked = cos_wi <= 0.0 || cos_wo <= 0.0;
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#endif
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if (is_blocked) {
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return vec3(/*diffuse*/0.0);
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}
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// if (cos_wo < 0.0) {
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// return /*vec3(0.0)*/diffuse;
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// }
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/* if (cos_wi == 0.0 || cos_wo == 0.0) {
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return vec3(0.0);
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} */
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/* if (wh.x == 0 && wh.y == 0 && wh.z == 0) {
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return vec3(0.0);
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// return Spectrum(0);
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} */
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wh = normalize(wh);//mix(normalize(wh), vec3(0.0), equal(light_dir, dir));
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float dot_wi_wh = dot(-light_dir, wh);
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vec3 specular = BeckmannDistribution_D(dot(wh, norm), alpha) /
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(4 * abs(dot_wi_wh) *
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max(abs(cos_wi), abs(cos_wo))) *
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schlick_fresnel(R_s, dot_wi_wh);
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// Spectrum specular = distribution->D(wh) /
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// (4 * AbsDot(wi, wh) *
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// std::max(AbsCosTheta(wi), AbsCosTheta(wo))) *
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// SchlickFresnel(Dot(wi, wh));
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return mix(/*diffuse*//* + specular*/diffuse + specular, vec3(0.0), bvec3(all(equal(light_dir, dir))));
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}
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// Fresnel blending
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//
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// http://www.pbr-book.org/3ed-2018/Reflection_Models/Microfacet_Models.html#fragment-MicrofacetDistributionPublicMethods-2
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// and
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// http://www.pbr-book.org/3ed-2018/Reflection_Models/Fresnel_Incidence_Effects.html
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vec3 FresnelBlend_Voxel_f(vec3 norm, vec3 dir, vec3 light_dir, vec3 R_d, vec3 R_s, float alpha, vec3 voxel_norm, float dist) {
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const float PI = 3.1415926535897932384626433832795;
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alpha = alpha * sqrt(2.0);
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float cos_wi = /*max(*/dot(-light_dir, norm)/*, 0.0)*/;
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float cos_wo = /*max(*/dot(dir, norm)/*, 0.0)*/;
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#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
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vec4 AbsNdotL = abs(vec4(light_dir, cos_wi));
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vec4 AbsNdotV = abs(vec4(dir, cos_wo));
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#else
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vec3 sides = sign(voxel_norm);
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vec4 AbsNdotL = vec4(max(-light_dir * sides, 0.0), abs(cos_wi));
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vec4 AbsNdotV = vec4(max(dir * sides, 0.0), abs(cos_wo));
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#endif
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// float R_r = 1.0 - R_s;
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// float R_r = 1.0 - schlick_fresnel(R_s, cos_wi);
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// // Rs + pow5(1.0 - cosTheta) * (1.0 - Rs)
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// vec4 R_r = 1.0 - (R_s + (1.0 - R_s) * schlick_fresnel(R_s, cos_wi));
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// mat4 R_r = 1.0 - (vec4(R_s, 0.0) + vec4(1.0 - R_s, 0.0) * pow5(1.0 - AbsNdotL));
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// vec4 AbsNdotL5 = pow5(1.0 - AbsNdotL);
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// vec4 R_s4 = vec4(R_s, 0.0);
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// mat4 R_r =
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// // mat4(1.0 - (R_s.r + (1.0 - R_s.r) * AbsNdotL5),
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// // 1.0 - (R_s.g + (1.0 - R_s.g) * AbsNdotL5),
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// // 1.0 - (R_s.b + (1.0 - R_s.b) * AbsNdotL5),
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// // vec4(0.0)
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// // );
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// mat4(1.0 - (R_s4 + (1.0 - R_s4) * AbsNdotL5.x),
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// 1.0 - (R_s4 + (1.0 - R_s4) * AbsNdotL5.y),
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// 1.0 - (R_s4 + (1.0 - R_s4) * AbsNdotL5.z),
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// 1.0 - (R_s4 + (1.0 - R_s4) * AbsNdotL5.w)
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// );
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// * ) (R1.0 - R_s.r) 1.0 - (vec4(R_s, 0.0) + vec4(1.0 - R_s, 0.0) * pow5(1.0 - AbsNdotL));
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vec4 diffuse_factor =
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// vec4(abs(vec4(-light_dir * sides, cos_wi)))
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(1.0 - pow5(1.0 - 0.5 * AbsNdotL)) *
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// (1.0 - pow5(1.0 - 0.5 * abs(vec4(-light_dir * sides, cos_wi)))) *
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// (1.0 - pow5(1.0 - 0.5 * abs(vec4(dir * sides, cos_wo))))
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(1.0 - pow5(1.0 - 0.5 * AbsNdotV))
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// vec4(1.0)
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;
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/* vec4 diffuse_factor =
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(1.0 - pow5(1.0 - 0.5 * max(vec4(-light_dir * sides, abs(cos_wi)), 0.0))) *
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(1.0 - pow5(1.0 - 0.5 * max(vec4(dir * sides, abs(cos_wo)), 0.0))); */
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vec3 diffuse = (28.0 / (23.0 * PI))/*(1.0 / PI)*/ * R_d *
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(1.0 - R_s) *
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//vec3(
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dot(diffuse_factor, /*R_r * */vec4(abs(norm) * (1.0 - dist), dist))
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//)
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;
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vec3 wh = -light_dir + dir;
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#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
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bool is_blocked = cos_wi == 0.0 || cos_wo == 0.0;
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#else
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bool is_blocked = cos_wi <= 0.0 || cos_wo <= 0.0;
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#endif
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if (is_blocked) {
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return vec3(/*diffuse*/0.0);
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}
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wh = normalize(wh);//mix(normalize(wh), vec3(0.0), equal(light_dir, dir));
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float dot_wi_wh = dot(-light_dir, wh);
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// float distr = TrowbridgeReitzDistribution_D_Voxel(wh, voxel_norm, alpha);
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float distr = BeckmannDistribution_D_Voxel(wh, voxel_norm, alpha);
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// float distr = BeckmannDistribution_D(dot(wh, norm), alpha);
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vec3 specular = distr /
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(4 * abs(dot_wi_wh) *
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max(abs(cos_wi), abs(cos_wo))) *
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schlick_fresnel(R_s, dot_wi_wh);
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return mix(/*diffuse*//* + specular*/diffuse + specular, vec3(0.0), bvec3(all(equal(light_dir, dir))));
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}
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// Phong reflection.
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//
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// Note: norm, dir, light_dir must all be normalizd.
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vec3 light_reflection_factor2(vec3 norm, vec3 dir, vec3 light_dir, vec3 k_d, vec3 k_s, float alpha) {
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// TODO: These are supposed to be the differential changes in the point location p, in tangent space.
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// That is, assuming we can parameterize a 2D surface by some function p : R² → R³, mapping from
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// points in a plane to 3D points on the surface, we can define
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// ∂p(u,v)/∂u and ∂p(u,v)/∂v representing the changes in the pont location as we move along these
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// coordinates.
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//
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// Then we can define the normal at a point, n(u,v) = ∂p(u,v)/∂u × ∂p(u,v)/∂v.
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//
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// Additionally, we can define the change in *normals* at each point using the
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// Weingarten equations (see http://www.pbr-book.org/3ed-2018/Shapes/Spheres.html):
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//
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// ∂n/∂u = (fF - eG) / (EG - F²) ∂p/∂u + (eF - fE) / (EG - F²) ∂p/∂v
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// ∂n/∂v = (gF - fG) / (EG - F²) ∂p/∂u + (fF - gE) / (EG - F²) ∂p/∂v
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//
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// where
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//
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// E = |∂p/∂u ⋅ ∂p/∂u|
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// F = ∂p/∂u ⋅ ∂p/∂u
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// G = |∂p/∂v ⋅ ∂p/∂v|
|
||
//
|
||
// and
|
||
//
|
||
// e = n ⋅ ∂²p/∂u²
|
||
// f = n ⋅ ∂²p/(∂u∂v)
|
||
// g = n ⋅ ∂²p/∂v²
|
||
//
|
||
// For planes (see http://www.pbr-book.org/3ed-2018/Shapes/Triangle_Meshes.html) we have
|
||
// e = f = g = 0 (since the plane has no curvature of any sort) so we get:
|
||
//
|
||
// ∂n/∂u = (0, 0, 0)
|
||
// ∂n/∂v = (0, 0, 0)
|
||
//
|
||
// To find ∂p/∂u and ∂p/∂v, we first write p and u parametrically:
|
||
// p(u, v) = p0 + u ∂p/∂u + v ∂p/∂v
|
||
//
|
||
// ( u₀ - u₂ v₀ - v₂
|
||
// u₁ - u₂ v₁ - v₂ )
|
||
//
|
||
// Basis: plane norm = norm = (0, 0, 1), x vector = any orthgonal vector on the plane.
|
||
// vec3 w_i =
|
||
// vec3 w_i = vec3(view_mat * vec4(-light_dir, 1.0));
|
||
// vec3 w_o = vec3(view_mat * vec4(light_dir, 1.0));
|
||
float g = 1.0;// BeckmannDistribution_G(norm, dir, light_dir, alpha);
|
||
return FresnelBlend_f(norm, dir, light_dir, k_d/* * max(dot(norm, -light_dir), 0.0)*/, k_s * g, alpha);
|
||
// const float PI = 3.141592;
|
||
// alpha = alpha * sqrt(2.0);
|
||
// float ndotL = /*max*/(dot(norm, -light_dir)/*, 0.0*/);
|
||
|
||
// //if (ndotL > 0.0/* && dot(s_norm, -light_dir) > 0.0*/) {
|
||
// vec3 H = normalize(-light_dir + dir);
|
||
|
||
// float NdotH = dot(norm, H);
|
||
// float NdotH2 = NdotH * NdotH;
|
||
// float NdotH2m2 = NdotH2 * alpha * alpha;
|
||
// float k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
|
||
// return mix(k_s * k_spec, vec3(0.0), bvec3(ndotL <= 0.0 || NdotH == 0.0));
|
||
// //
|
||
// // (k_d * (L ⋅ N) + k_s * (R ⋅ V)^α)
|
||
// // return k_d * ndotL + mix(k_s * pow(max(dot(norm, H), 0.0), alpha * 4.0), vec3(0.0), bvec3(ndotL == 0.0));
|
||
// // }
|
||
// // return vec3(0.0);
|
||
}
|
||
|
||
vec3 light_reflection_factor(vec3 norm, vec3 dir, vec3 light_dir, vec3 k_d, vec3 k_s, float alpha, vec3 voxel_norm, float voxel_lighting) {
|
||
#if (LIGHTING_ALGORITHM == LIGHTING_ALGORITHM_LAMBERTIAN)
|
||
const float PI = 3.141592;
|
||
#if (LIGHTING_DISTRIBUTION_SCHEME == LIGHTING_DISTRIBUTION_SCHEME_VOXEL)
|
||
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
|
||
vec4 AbsNdotL = abs(vec4(light_dir, dot(norm, light_dir)));
|
||
#else
|
||
vec3 sides = sign(voxel_norm);
|
||
vec4 AbsNdotL = max(vec4(-light_dir * sides, dot(norm, -light_dir)), 0.0);
|
||
#endif
|
||
float diffuse = dot(AbsNdotL, vec4(abs(voxel_norm) * (1.0 - voxel_lighting), voxel_lighting));
|
||
#elif (LIGHTING_DISTRIBUTION_SCHEME == LIGHTING_DISTRIBUTION_SCHEME_MICROFACET)
|
||
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
|
||
float diffuse = abs(dot(norm, light_dir));
|
||
#else
|
||
float diffuse = max(dot(norm, -light_dir), 0.0);
|
||
#endif
|
||
#endif
|
||
return k_d / PI * diffuse;
|
||
#elif (LIGHTING_ALGORITHM == LIGHTING_ALGORITHM_BLINN_PHONG)
|
||
const float PI = 3.141592;
|
||
alpha = alpha * sqrt(2.0);
|
||
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
|
||
float ndotL = abs(dot(norm, light_dir));
|
||
#else
|
||
float ndotL = max(dot(norm, -light_dir), 0.0);
|
||
#endif
|
||
|
||
if (ndotL > 0.0) {
|
||
#if (LIGHTING_DISTRIBUTION_SCHEME == LIGHTING_DISTRIBUTION_SCHEME_VOXEL)
|
||
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
|
||
vec4 AbsNdotL = abs(vec4(light_dir, ndotL));
|
||
#else
|
||
vec3 sides = sign(voxel_norm);
|
||
vec4 AbsNdotL = max(vec4(-light_dir * sides, ndotL), 0.0);
|
||
#endif
|
||
float diffuse = dot(AbsNdotL, vec4(abs(voxel_norm) * (1.0 - voxel_lighting), voxel_lighting));
|
||
#elif (LIGHTING_DISTRIBUTION_SCHEME == LIGHTING_DISTRIBUTION_SCHEME_MICROFACET)
|
||
float diffuse = ndotL;
|
||
#endif
|
||
vec3 H = normalize(-light_dir + dir);
|
||
|
||
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
|
||
float NdotH = abs(dot(norm, H));
|
||
#else
|
||
float NdotH = max(dot(norm, H), 0.0);
|
||
#endif
|
||
return (1.0 - k_s) / PI * k_d * diffuse + k_s * pow(NdotH, alpha/* * 4.0*/);
|
||
}
|
||
|
||
return vec3(0.0);
|
||
#elif (LIGHTING_ALGORITHM == LIGHTING_ALGORITHM_ASHIKHMIN)
|
||
#if (LIGHTING_DISTRIBUTION_SCHEME == LIGHTING_DISTRIBUTION_SCHEME_VOXEL)
|
||
return FresnelBlend_Voxel_f(norm, dir, light_dir, k_d/* * max(dot(norm, -light_dir), 0.0)*/, k_s, alpha, voxel_norm, voxel_lighting);
|
||
#elif (LIGHTING_DISTRIBUTION_SCHEME == LIGHTING_DISTRIBUTION_SCHEME_MICROFACET)
|
||
//if (voxel_lighting < 1.0) {
|
||
return FresnelBlend_f(norm, dir, light_dir, k_d/* * max(dot(norm, -light_dir), 0.0)*/, k_s, alpha);
|
||
//} else {
|
||
// return FresnelBlend_f(norm, dir, light_dir, k_d/* * max(dot(norm, -light_dir), 0.0)*/, k_s, alpha);
|
||
//}
|
||
#endif
|
||
#endif
|
||
}
|
||
|
||
float rel_luminance(vec3 rgb)
|
||
{
|
||
// https://en.wikipedia.org/wiki/Relative_luminance
|
||
const vec3 W = vec3(0.2126, 0.7152, 0.0722);
|
||
return dot(rgb, W);
|
||
}
|
||
|
||
// From https://discourse.vvvv.org/t/infinite-ray-intersects-with-infinite-plane/10537
|
||
// out of laziness.
|
||
bool IntersectRayPlane(vec3 rayOrigin, vec3 rayDirection, vec3 posOnPlane, vec3 planeNormal, inout vec3 intersectionPoint)
|
||
{
|
||
float rDotn = dot(rayDirection, planeNormal);
|
||
|
||
//parallel to plane or pointing away from plane?
|
||
if (rDotn < 0.0000001 )
|
||
return false;
|
||
|
||
float s = dot(planeNormal, (posOnPlane - rayOrigin)) / rDotn;
|
||
|
||
intersectionPoint = rayOrigin + s * rayDirection;
|
||
|
||
return true;
|
||
}
|
||
|
||
// Compute uniform attenuation due to beam passing through a substance that fills an area below a horizontal plane
|
||
// (e.g. in most cases, water below the water surface depth) using the simplest form of the Beer-Lambert law
|
||
// (https://en.wikipedia.org/wiki/Beer%E2%80%93Lambert_law):
|
||
//
|
||
// I(z) = I₀ e^(-μz)
|
||
//
|
||
// We compute this value, except for the initial intensity which may be multiplied out later.
|
||
//
|
||
// wpos is the position of the point being hit.
|
||
// ray_dir is the reversed direction of the ray (going "out" of the point being hit).
|
||
// mu is the attenuation coefficient for R, G, and B wavelenghts.
|
||
// surface_alt is the estimated altitude of the horizontal surface separating the substance from air.
|
||
// defaultpos is the position to use in computing the distance along material at this point if there was a failure.
|
||
//
|
||
// Ideally, defaultpos is set so we can avoid branching on error.
|
||
vec3 compute_attenuation(vec3 wpos, vec3 ray_dir, vec3 mu, float surface_alt, vec3 defaultpos) {
|
||
#if (LIGHTING_TRANSPORT_MODE == LIGHTING_TRANSPORT_MODE_IMPORTANCE)
|
||
return vec3(1.0);
|
||
#elif (LIGHTING_TRANSPORT_MODE == LIGHTING_TRANSPORT_MODE_RADIANCE)
|
||
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
|
||
return vec3(1.0);
|
||
#else
|
||
// return vec3(1.0);
|
||
/*if (mu == vec3(0.0)) {
|
||
return vec3(1.0);
|
||
}*//* else {
|
||
return vec3(0.0);
|
||
}*/
|
||
// return vec3(0.0);
|
||
// vec3 surface_dir = /*surface_alt < wpos.z ? vec3(0.0, 0.0, -1.0) : vec3(0.0, 0.0, 1.0)*/vec3(0.0, 0.0, sign(surface_alt - wpos.z));
|
||
ray_dir = faceforward(ray_dir, vec3(0.0, 0.0, -1.0), ray_dir);
|
||
vec3 surface_dir = surface_alt < wpos.z ? vec3(0.0, 0.0, -1.0) : vec3(0.0, 0.0, 1.0);
|
||
// vec3 surface_dir = faceforward(vec3(0.0, 0.0, 1.0), ray_dir, vec3(0.0, 0.0, 1.0));
|
||
bool _intersects_surface = IntersectRayPlane(wpos, ray_dir, vec3(0.0, 0.0, surface_alt), surface_dir, defaultpos);
|
||
float depth = length(defaultpos - wpos);
|
||
return exp(-mu * depth);
|
||
#endif
|
||
#endif
|
||
}
|
||
|
||
// vec3 compute_attenuation2(vec3 wpos, vec3 ray_dir, vec3 mu, float surface_alt, vec3 defaultpos) {
|
||
// #if (LIGHTING_TRANSPORT_MODE == LIGHTING_TRANSPORT_MODE_IMPORTANCE)
|
||
// return vec3(1.0);
|
||
// #elif (LIGHTING_TRANSPORT_MODE == LIGHTING_TRANSPORT_MODE_RADIANCE)
|
||
// // return vec3(1.0);
|
||
// /*if (mu == vec3(0.0)) {
|
||
// return vec3(1.0);
|
||
// }*//* else {
|
||
// return vec3(0.0);
|
||
// }*/
|
||
// // return vec3(0.0);
|
||
// // vec3 surface_dir = /*surface_alt < wpos.z ? vec3(0.0, 0.0, -1.0) : vec3(0.0, 0.0, 1.0)*/vec3(0.0, 0.0, sign(surface_alt - wpos.z));
|
||
// vec3 surface_dir = surface_alt < wpos.z ? vec3(0.0, 0.0, 1.0) : vec3(0.0, 0.0, -1.0);
|
||
// // vec3 surface_dir = faceforward(vec3(0.0, 0.0, 1.0), ray_dir, vec3(0.0, 0.0, 1.0));
|
||
// bool _intersects_surface = IntersectRayPlane(wpos, ray_dir, vec3(0.0, 0.0, surface_alt), surface_dir, defaultpos);
|
||
// float depth = length(defaultpos - wpos);
|
||
// return exp(-mu * depth);
|
||
// #endif
|
||
// }
|
||
|
||
// Same as compute_attenuation but since both point are known, set a maximum to make sure we don't exceed the length
|
||
// from the default point.
|
||
vec3 compute_attenuation_point(vec3 wpos, vec3 ray_dir, vec3 mu, float surface_alt, vec3 defaultpos) {
|
||
#if (LIGHTING_TRANSPORT_MODE == LIGHTING_TRANSPORT_MODE_IMPORTANCE)
|
||
return vec3(1.0);
|
||
#elif (LIGHTING_TRANSPORT_MODE == LIGHTING_TRANSPORT_MODE_RADIANCE)
|
||
// return vec3(1.0);
|
||
/*if (mu == vec3(0.0)) {
|
||
return vec3(1.0);
|
||
}*//* else {
|
||
return vec3(0.0);
|
||
}*/
|
||
// return vec3(0.0);
|
||
vec3 surface_dir = /*surface_alt < wpos.z ? vec3(0.0, 0.0, -1.0) : vec3(0.0, 0.0, 1.0)*/vec3(0.0, 0.0, sign(wpos.z - surface_alt));
|
||
// vec3 surface_dir = surface_alt < wpos.z ? vec3(0.0, 0.0, 1.0) : vec3(0.0, 0.0, -1.0);
|
||
// vec3 surface_dir = faceforward(vec3(0.0, 0.0, 1.0), ray_dir, vec3(0.0, 0.0, 1.0));
|
||
float max_length = dot(defaultpos - wpos, defaultpos - wpos);
|
||
bool _intersects_surface = IntersectRayPlane(wpos, ray_dir, vec3(0.0, 0.0, surface_alt), surface_dir, defaultpos);
|
||
float depth2 = min(max_length, dot(defaultpos - wpos, defaultpos - wpos));
|
||
return exp(-mu * sqrt(depth2));
|
||
#endif
|
||
}
|
||
|
||
//#ifdef HAS_SHADOW_MAPS
|
||
// #if (SHADOW_MODE == SHADOW_MODE_MAP)
|
||
//uniform sampler2DShadow t_directed_shadow_maps;
|
||
//// uniform sampler2DArrayShadow t_directed_shadow_maps;
|
||
//
|
||
//float ShadowCalculationDirected(in vec4 /*light_pos[2]*/sun_pos, uint lightIndex)
|
||
//{
|
||
// float bias = 0.0;//-0.0001;// 0.05 / (2.0 * view_distance.x);
|
||
// // const vec3 sampleOffsetDirections[20] = vec3[]
|
||
// // (
|
||
// // vec3( 1, 1, 1), vec3( 1, -1, 1), vec3(-1, -1, 1), vec3(-1, 1, 1),
|
||
// // vec3( 1, 1, -1), vec3( 1, -1, -1), vec3(-1, -1, -1), vec3(-1, 1, -1),
|
||
// // vec3( 1, 1, 0), vec3( 1, -1, 0), vec3(-1, -1, 0), vec3(-1, 1, 0),
|
||
// // vec3( 1, 0, 1), vec3(-1, 0, 1), vec3( 1, 0, -1), vec3(-1, 0, -1),
|
||
// // vec3( 0, 1, 1), vec3( 0, -1, 1), vec3( 0, -1, -1), vec3( 0, 1, -1)
|
||
// // // vec3(0, 0, 0)
|
||
// // );
|
||
// /* if (lightIndex >= light_shadow_count.z) {
|
||
// return 1.0;
|
||
// } */
|
||
// // vec3 fragPos = sun_pos.xyz;// / sun_pos.w;//light_pos[lightIndex].xyz;
|
||
// float visibility = textureProj(t_directed_shadow_maps, sun_pos);
|
||
// // float visibility = textureProj(t_directed_shadow_maps, vec4(fragPos.xy, /*lightIndex, */fragPos.z + bias, sun_pos.w));
|
||
// return visibility;
|
||
// // return mix(visibility, 0.0, sun_pos.z < -1.0);
|
||
// // return mix(mix(0.0, 1.0, visibility == 1.0), 1.0, sign(sun_pos.w) * sun_pos.z > /*1.0*/abs(sun_pos.w));
|
||
// // return visibility == 1.0 ? 1.0 : 0.0;
|
||
// /* if (visibility == 1.0) {
|
||
// return 1.0;
|
||
// } */
|
||
// // return visibility;
|
||
// /* if (fragPos.z > 1.0) {
|
||
// return 1.0;
|
||
// } */
|
||
// // if (visibility <= 0.75) {
|
||
// // return 0.0;
|
||
// // }
|
||
// // int samples = 20;
|
||
// // float shadow = 0.0;
|
||
// // // float bias = 0.0001;
|
||
// // float viewDistance = length(cam_pos.xyz - fragPos);
|
||
// // // float diskRadius = 0.2 * (1.0 + (viewDistance / screen_res.w)) / 25.0;
|
||
// // float diskRadius = 0.0008;//0.005;// / (2.0 * view_distance.x);//(1.0 + (viewDistance / screen_res.w)) / 25.0;
|
||
// // for(int i = 0; i < samples; ++i)
|
||
// // {
|
||
// // vec3 currentDepth = fragPos + vec3(sampleOffsetDirections[i].xyz) * diskRadius + bias;
|
||
// // visibility = texture(t_directed_shadow_maps, vec4(currentDepth.xy, lightIndex, currentDepth.z)/*, -2.5*/);
|
||
// // shadow += mix(visibility, 1.0, visibility >= 0.5);
|
||
// // }
|
||
// // shadow /= float(samples);
|
||
// // return shadow;
|
||
//}
|
||
// #elif (SHADOW_MODE == SHADOW_MODE_NONE || SHADOW_MODE == SHADOW_MODE_CHEAP)
|
||
//float ShadowCalculationDirected(in vec4 light_pos[2], uint lightIndex)
|
||
//{
|
||
// return 1.0;
|
||
//}
|
||
// #endif
|
||
//#else
|
||
//float ShadowCalculationDirected(in vec4 light_pos[2], uint lightIndex)
|
||
//{
|
||
// return 1.0;
|
||
//}
|
||
//#endif
|