group_bot/assets/voxygen/shaders/include/srgb.glsl
2024-06-13 19:16:24 -04:00

674 lines
29 KiB
GLSL
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#ifndef SRGB_GLSL
#define SRGB_GLSL
#extension GL_EXT_samplerless_texture_functions : enable
// Linear RGB, attenuation coefficients for water at roughly R, G, B wavelengths.
// See https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_water
const vec3 MU_WATER = vec3(0.6, 0.04, 0.01);
// // NOTE: Automatic in v4.0
// float
// mip_map_level(in vec2 texture_coordinate)
// {
// // The OpenGL Graphics System: A Specification 4.2
// // - chapter 3.9.11, equation 3.21
//
//
// vec2 dx_vtc = dFdx(texture_coordinate);
// vec2 dy_vtc = dFdy(texture_coordinate);
// float delta_max_sqr = max(dot(dx_vtc, dx_vtc), dot(dy_vtc, dy_vtc));
//
//
// //return max(0.0, 0.5 * log2(delta_max_sqr) - 1.0); // == log2(sqrt(delta_max_sqr));
// return 0.5 * log2(delta_max_sqr); // == log2(sqrt(delta_max_sqr));
// }
//https://gamedev.stackexchange.com/questions/92015/optimized-linear-to-srgb-glsl
vec3 srgb_to_linear(vec3 srgb) {
bvec3 cutoff = lessThan(srgb, vec3(0.04045));
vec3 higher = pow((srgb + vec3(0.055))/vec3(1.055), vec3(2.4));
vec3 lower = srgb/vec3(12.92);
return mix(higher, lower, cutoff);
}
vec3 linear_to_srgb(vec3 col) {
// bvec3 cutoff = lessThan(col, vec3(0.0060));
// return mix(11.500726 * col, , cutoff);
vec3 s1 = vec3(sqrt(col.r), sqrt(col.g), sqrt(col.b));
vec3 s2 = vec3(sqrt(s1.r), sqrt(s1.g), sqrt(s1.b));
vec3 s3 = vec3(sqrt(s2.r), sqrt(s2.g), sqrt(s2.b));
return vec3(
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)),
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)),
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))
);
}
float pow5(float x) {
float x2 = x * x;
return x2 * x2 * x;
}
vec4 pow5(vec4 x) {
vec4 x2 = x * x;
return x2 * x2 * x;
}
// Fresnel angle for perfectly specular dialectric materials.
// Schlick approximation
vec3 schlick_fresnel(vec3 Rs, float cosTheta) {
// auto pow5 = [](Float v) { return (v * v) * (v * v) * v; };
// return Rs + pow5(1 - cosTheta) * (Spectrum(1.) - Rs);
return Rs + pow5(1.0 - cosTheta) * (1.0 - Rs);
}
// Beckmann Distribution
float BeckmannDistribution_D(float NdotH, float alpha) {
const float PI = 3.1415926535897932384626433832795;
float NdotH2 = NdotH * NdotH;
float NdotH2m2 = NdotH2 * alpha * alpha;
float k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
return mix(k_spec, 0.0, NdotH == 0.0);
}
// Voxel Distribution
float BeckmannDistribution_D_Voxel(vec3 wh, vec3 voxel_norm, float alpha) {
vec3 sides = sign(voxel_norm);
// vec3 cos_sides_i = /*sides * */sides * norm;
// vec3 cos_sides_o = max(sides * view_dir, 0.0);
vec3 NdotH = wh * sides;//max(wh * sides, 0.0);/*cos_sides_i*///max(sides * wh, 0.0);
const float PI = 3.1415926535897932384626433832795;
vec3 NdotH2 = NdotH * NdotH;
vec3 NdotH2m2 = NdotH2 * alpha * alpha;
vec3 k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
return dot(mix(k_spec, /*cos_sides_o*/vec3(0.0), equal(NdotH, vec3(0.0))), /*cos_sides_i*/abs(voxel_norm));
// // const float PI = 3.1415926535897932384626433832795;
// 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));
// float voxel_norm = 0.0;
// for (int i = 0; i < 6; i ++) {
// // Light reflecting off the half-angle can shine on up to three sides.
// // So, the idea here is to figure out the ratio of visibility of each of these
// // three sides such that their sum adds to 1, then computing a Beckmann Distribution for each side times
// // the this ratio.
// //
// // The ratio of these normals in each direction should be the sum of their cosines with the light over π,
// // I think.
// //
// // cos (wh, theta)
// //
// // - one normal
// //
// // The ratio of each of the three exposed sides should just be the slope.
// vec3 side = normals[i];
// float side_share = max(dot(norm, side), 0.0);
// float NdotH = max(dot(wh, side), 0.0);
// voxel_norm += side_share * BeckmannDistribution_D(NdotH, alpha);
// // voxel_norm += normals[i] * side_visible * max(dot(-cam_dir, normals[i]), 0.0);
// // voxel_norm += normals[i] * side_visible * max(dot(-cam_dir, normals[i]), 0.0);
// }
// /* float NdotH = dot(wh, norm);
// float NdotH2 = NdotH * NdotH;
// float NdotH2m2 = NdotH2 * alpha * alpha;
// float k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
// return mix(k_spec, 0.0, NdotH == 0.0); */
// return voxel_norm;
}
float TrowbridgeReitzDistribution_D_Voxel(vec3 wh, vec3 voxel_norm, float alpha) {
vec3 sides = sign(voxel_norm);
// vec3 cos_sides_i = /*sides * */sides * norm;
// vec3 cos_sides_o = max(sides * view_dir, 0.0);
vec3 NdotH = wh * sides;//max(wh * sides, 0.0);/*cos_sides_i*///max(sides * wh, 0.0);
const float PI = 3.1415926535897932384626433832795;
vec3 NdotH2 = NdotH * NdotH;
// vec3 m2 = alpha * alpha;
// vec3 NdotH2m2 = NdotH2 * m2;
vec3 NdotH2m2 = NdotH2 * alpha * alpha;
// vec3 Tan2Theta = (1 - NdotH2) / NdotH2;
// vec3 e = (NdotH2 / m2 + (1 - NdotH2) / m2) * Tan2Theta;
// vec3 e = 1 / m2 * (1 - NdotH2) / NdotH2;
vec3 e = (1 - NdotH2) / NdotH2m2;
vec3 k_spec = 1.0 / (PI * NdotH2m2 * NdotH2 * (1 + e) * (1 + e));
// vec3 k_spec = exp((NdotH2 - 1) / NdotH2m2) / (PI * NdotH2m2 * NdotH2);
return dot(mix(k_spec, /*cos_sides_o*/vec3(0.0), equal(NdotH, vec3(0.0))), /*cos_sides_i*/abs(voxel_norm));
}
float BeckmannDistribution_Lambda(vec3 norm, vec3 dir, float alpha) {
float CosTheta = /*max(dot(norm, dir), 0.0);*/dot(norm, dir);
/* if (CosTheta == 0.0) {
return 0.0;
}
float SinTheta = sqrt(1.0 - CosTheta * CosTheta);
float TanTheta = SinTheta / CosTheta;
float absTanTheta = abs(TanTheta); */
// vec3 w = normalize(dir - dot(dir, norm) * (norm));
// float CosTheta = w.z;
float SinTheta = sqrt(1.0 - CosTheta * CosTheta);
float TanTheta = SinTheta / CosTheta;
float absTanTheta = abs(TanTheta);
/* if (isinf(absTanTheta)) {
return 0.0;
} */
/* float CosPhi = mix(clamp(projDirNorm.x / sinTheta, -1.0, 1.0), 0.0, sinTheta == 0.0);
float SinPhi = mix(clamp(projDirNorm.y / sinTheta, -1.0, 1.0), 0.0, sinTheta == 0.0);
float alpha = sqrt(CosPhi * CosPhi * alphax * alphax + SinPhi * SinPhi * alphay * alphay); */
// Float absTanTheta = std::abs(TanTheta(w));
// if (std::isinf(absTanTheta)) return 0.;
// <<Compute alpha for direction w>>
// Float alpha = std::sqrt(Cos2Phi(w) * alphax * alphax +
// Sin2Phi(w) * alphay * alphay);
float a = 1.0 / (alpha * absTanTheta);
/* if (a >= 1.6) {
return 0.0;
}
return (1.0 - 1.259 * a + 0.396 * a * a) / (3.535 * a + 2.181 * a * a); */
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);
// Float a = 1 / (alpha * absTanTheta);
// if (a >= 1.6f)
// return 0;
// return (1 - 1.259f * a + 0.396f * a * a) /
// (3.535f * a + 2.181f * a * a);
// return 1 / (1 + Lambda(wo) + Lambda(wi));
}
float BeckmannDistribution_G(vec3 norm, vec3 dir, vec3 light_dir, float alpha) {
// return 1 / (1 + Lambda(wo) + Lambda(wi));
return 1.0 / (1.0 + BeckmannDistribution_Lambda(norm, dir, alpha) + BeckmannDistribution_Lambda(norm, -light_dir, alpha));
}
// Fresnel blending
//
// http://www.pbr-book.org/3ed-2018/Reflection_Models/Microfacet_Models.html#fragment-MicrofacetDistributionPublicMethods-2
// and
// http://www.pbr-book.org/3ed-2018/Reflection_Models/Fresnel_Incidence_Effects.html
vec3 FresnelBlend_f(vec3 norm, vec3 dir, vec3 light_dir, vec3 R_d, vec3 R_s, float alpha) {
const float PI = 3.1415926535897932384626433832795;
alpha = alpha * sqrt(2.0);
float cos_wi = /*max(*/dot(-light_dir, norm)/*, 0.0)*/;
float cos_wo = /*max(*/dot(dir, norm)/*, 0.0)*/;
vec3 diffuse = (28.0 / (23.0 * PI)) * R_d *
(1.0 - R_s) *
(1.0 - pow5(1.0 - 0.5 * abs(cos_wi))) *
(1.0 - pow5(1.0 - 0.5 * abs(cos_wo)));
/* Spectrum diffuse = (28.f/(23.f*Pi)) * Rd *
(Spectrum(1.f) - Rs) *
(1 - pow5(1 - .5f * AbsCosTheta(wi))) *
(1 - pow5(1 - .5f * AbsCosTheta(wo))); */
// Vector3f wh = wi + wo;
vec3 wh = -light_dir + dir;
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
bool is_blocked = cos_wi == 0.0 || cos_wo == 0.0;
#else
bool is_blocked = cos_wi <= 0.0 || cos_wo <= 0.0;
#endif
if (is_blocked) {
return vec3(/*diffuse*/0.0);
}
// if (cos_wo < 0.0) {
// return /*vec3(0.0)*/diffuse;
// }
/* if (cos_wi == 0.0 || cos_wo == 0.0) {
return vec3(0.0);
} */
/* if (wh.x == 0 && wh.y == 0 && wh.z == 0) {
return vec3(0.0);
// return Spectrum(0);
} */
wh = normalize(wh);//mix(normalize(wh), vec3(0.0), equal(light_dir, dir));
float dot_wi_wh = dot(-light_dir, wh);
vec3 specular = dot(norm, dir) > 0.0 ? vec3(0.0) : (BeckmannDistribution_D(dot(wh, norm), alpha) /
(4 * abs(dot_wi_wh) *
max(abs(cos_wi), abs(cos_wo))) *
schlick_fresnel(R_s, dot_wi_wh));
// Spectrum specular = distribution->D(wh) /
// (4 * AbsDot(wi, wh) *
// std::max(AbsCosTheta(wi), AbsCosTheta(wo))) *
// SchlickFresnel(Dot(wi, wh));
return mix(/*diffuse*//* + specular*/diffuse + specular, vec3(0.0), bvec3(all(equal(light_dir, dir))));
}
// Fresnel blending
//
// http://www.pbr-book.org/3ed-2018/Reflection_Models/Microfacet_Models.html#fragment-MicrofacetDistributionPublicMethods-2
// and
// http://www.pbr-book.org/3ed-2018/Reflection_Models/Fresnel_Incidence_Effects.html
vec3 FresnelBlend_Voxel_f(vec3 norm, vec3 dir, vec3 light_dir, vec3 R_d, vec3 R_s, float alpha, vec3 voxel_norm, float dist) {
const float PI = 3.1415926535897932384626433832795;
alpha = alpha * sqrt(2.0);
float cos_wi = /*max(*/dot(-light_dir, norm)/*, 0.0)*/;
float cos_wo = /*max(*/dot(dir, norm)/*, 0.0)*/;
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
vec4 AbsNdotL = abs(vec4(light_dir, cos_wi));
vec4 AbsNdotV = abs(vec4(dir, cos_wo));
#else
vec3 sides = sign(voxel_norm);
vec4 AbsNdotL = vec4(max(-light_dir * sides, 0.0), abs(cos_wi));
vec4 AbsNdotV = vec4(max(dir * sides, 0.0), abs(cos_wo));
#endif
// float R_r = 1.0 - R_s;
// float R_r = 1.0 - schlick_fresnel(R_s, cos_wi);
// // Rs + pow5(1.0 - cosTheta) * (1.0 - Rs)
// vec4 R_r = 1.0 - (R_s + (1.0 - R_s) * schlick_fresnel(R_s, cos_wi));
// mat4 R_r = 1.0 - (vec4(R_s, 0.0) + vec4(1.0 - R_s, 0.0) * pow5(1.0 - AbsNdotL));
// vec4 AbsNdotL5 = pow5(1.0 - AbsNdotL);
// vec4 R_s4 = vec4(R_s, 0.0);
// mat4 R_r =
// // mat4(1.0 - (R_s.r + (1.0 - R_s.r) * AbsNdotL5),
// // 1.0 - (R_s.g + (1.0 - R_s.g) * AbsNdotL5),
// // 1.0 - (R_s.b + (1.0 - R_s.b) * AbsNdotL5),
// // vec4(0.0)
// // );
// mat4(1.0 - (R_s4 + (1.0 - R_s4) * AbsNdotL5.x),
// 1.0 - (R_s4 + (1.0 - R_s4) * AbsNdotL5.y),
// 1.0 - (R_s4 + (1.0 - R_s4) * AbsNdotL5.z),
// 1.0 - (R_s4 + (1.0 - R_s4) * AbsNdotL5.w)
// );
// * ) (R1.0 - R_s.r) 1.0 - (vec4(R_s, 0.0) + vec4(1.0 - R_s, 0.0) * pow5(1.0 - AbsNdotL));
vec4 diffuse_factor =
// vec4(abs(vec4(-light_dir * sides, cos_wi)))
(1.0 - pow5(1.0 - 0.5 * AbsNdotL)) *
// (1.0 - pow5(1.0 - 0.5 * abs(vec4(-light_dir * sides, cos_wi)))) *
// (1.0 - pow5(1.0 - 0.5 * abs(vec4(dir * sides, cos_wo))))
(1.0 - pow5(1.0 - 0.5 * AbsNdotV))
// vec4(1.0)
;
/* vec4 diffuse_factor =
(1.0 - pow5(1.0 - 0.5 * max(vec4(-light_dir * sides, abs(cos_wi)), 0.0))) *
(1.0 - pow5(1.0 - 0.5 * max(vec4(dir * sides, abs(cos_wo)), 0.0))); */
vec3 diffuse = (28.0 / (23.0 * PI))/*(1.0 / PI)*/ * R_d *
(1.0 - R_s) *
//vec3(
dot(diffuse_factor, /*R_r * */vec4(abs(norm) * (1.0 - dist), dist))
//)
;
vec3 wh = -light_dir + dir;
#if (LIGHTING_TYPE & LIGHTING_TYPE_TRANSMISSION) != 0
bool is_blocked = cos_wi == 0.0 || cos_wo == 0.0;
#else
bool is_blocked = cos_wi <= 0.0 || cos_wo <= 0.0;
#endif
if (is_blocked) {
return vec3(/*diffuse*/0.0);
}
wh = normalize(wh);//mix(normalize(wh), vec3(0.0), equal(light_dir, dir));
float dot_wi_wh = dot(-light_dir, wh);
// float distr = TrowbridgeReitzDistribution_D_Voxel(wh, voxel_norm, alpha);
float distr = BeckmannDistribution_D_Voxel(wh, voxel_norm, alpha);
// float distr = BeckmannDistribution_D(dot(wh, norm), alpha);
vec3 specular = distr /
(4 * abs(dot_wi_wh) *
max(abs(cos_wi), abs(cos_wo))) *
schlick_fresnel(R_s, dot_wi_wh);
return mix(/*diffuse*//* + specular*/diffuse + specular, vec3(0.0), bvec3(all(equal(light_dir, dir))));
}
// Phong reflection.
//
// Note: norm, dir, light_dir must all be normalizd.
vec3 light_reflection_factor2(vec3 norm, vec3 dir, vec3 light_dir, vec3 k_d, vec3 k_s, float alpha) {
// TODO: These are supposed to be the differential changes in the point location p, in tangent space.
// That is, assuming we can parameterize a 2D surface by some function p : R² → R³, mapping from
// points in a plane to 3D points on the surface, we can define
// ∂p(u,v)/∂u and ∂p(u,v)/∂v representing the changes in the pont location as we move along these
// coordinates.
//
// Then we can define the normal at a point, n(u,v) = ∂p(u,v)/∂u × ∂p(u,v)/∂v.
//
// Additionally, we can define the change in *normals* at each point using the
// Weingarten equations (see http://www.pbr-book.org/3ed-2018/Shapes/Spheres.html):
//
// ∂n/∂u = (fF - eG) / (EG - F²) ∂p/∂u + (eF - fE) / (EG - F²) ∂p/∂v
// ∂n/∂v = (gF - fG) / (EG - F²) ∂p/∂u + (fF - gE) / (EG - F²) ∂p/∂v
//
// where
//
// E = |∂p/∂u ⋅ ∂p/∂u|
// F = ∂p/∂u ⋅ ∂p/∂u
// 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 pow(1.0 - mu, vec3(3));
#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
vec3 greedy_extract_col_light_attr(texture2D t_col_light, sampler s_col_light, vec2 f_uv_pos, out float f_light, out float f_glow, out float f_ao, out uint f_attr, out float f_sky_exposure) {
// TODO: Figure out how to use `texture` and modulation to avoid needing to do manual filtering
// TODO: Use `texture` instead
//vec2 light = texture(t_col_light, f_uv_pos).xy / 31;
uvec4 tex_00 = uvec4(texelFetch(sampler2D(t_col_light, s_col_light), ivec2(f_uv_pos) + ivec2(0, 0), 0) * 255);
uvec4 tex_10 = uvec4(texelFetch(sampler2D(t_col_light, s_col_light), ivec2(f_uv_pos) + ivec2(1, 0), 0) * 255);
uvec4 tex_01 = uvec4(texelFetch(sampler2D(t_col_light, s_col_light), ivec2(f_uv_pos) + ivec2(0, 1), 0) * 255);
uvec4 tex_11 = uvec4(texelFetch(sampler2D(t_col_light, s_col_light), ivec2(f_uv_pos) + ivec2(1, 1), 0) * 255);
vec3 light_00 = vec3(tex_00.rg >> 3u, tex_00.a & 1u);
vec3 light_10 = vec3(tex_10.rg >> 3u, tex_10.a & 1u);
vec3 light_01 = vec3(tex_01.rg >> 3u, tex_01.a & 1u);
vec3 light_11 = vec3(tex_11.rg >> 3u, tex_11.a & 1u);
vec3 light_0 = mix(light_00, light_01, fract(f_uv_pos.y));
vec3 light_1 = mix(light_10, light_11, fract(f_uv_pos.y));
vec3 light = mix(light_0, light_1, fract(f_uv_pos.x));
vec3 f_col = vec3(
float(((tex_00.r & 0x7u) << 1u) | (tex_00.b & 0xF0u)),
float(tex_00.a & 0xFE),
float(((tex_00.g & 0x7u) << 1u) | ((tex_00.b & 0x0Fu) << 4u))
) / 255.0;
f_ao = light.z;
f_light = light.x / 31.0;
f_sky_exposure = light.x / 31.0 + (1.0 - f_ao) * 0.5;
f_glow = light.y / 31.0;
f_attr = tex_00.g >> 3u;
return srgb_to_linear(f_col);
}
vec3 greedy_extract_col_light_kind_terrain(
texture2D t_col_light, sampler s_col_light,
utexture2D t_kind,
vec2 f_uv_pos,
out float f_light, out float f_glow, out float f_ao, out float f_sky_exposure, out uint f_kind
) {
float _f_attr;
f_kind = uint(texelFetch(t_kind, ivec2(f_uv_pos), 0).r);
return greedy_extract_col_light_attr(t_col_light, s_col_light, f_uv_pos, f_light, f_glow, f_ao, _f_attr, f_sky_exposure);
}
vec3 greedy_extract_col_light_figure(texture2D t_col_light, sampler s_col_light, vec2 f_uv_pos, out float f_light, out uint f_attr) {
float _f_sky_exposure, _f_light, _f_glow, _f_ao;
return greedy_extract_col_light_attr(t_col_light, s_col_light, f_uv_pos, f_light, _f_glow, _f_ao, f_attr, _f_sky_exposure);
}
#endif