Merge pull request #69514 from clayjohn/IBL-roughness

Properly remap roughness when reading from radiance map
This commit is contained in:
Rémi Verschelde 2022-12-03 12:46:25 +01:00
commit 29ddbfa19a
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GPG key ID: C3336907360768E1
5 changed files with 10 additions and 19 deletions

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@ -1100,7 +1100,7 @@ void main() {
ref_vec = mix(ref_vec, normal, roughness * roughness);
float horizon = min(1.0 + dot(ref_vec, normal), 1.0);
ref_vec = scene_data.radiance_inverse_xform * ref_vec;
specular_light = textureLod(radiance_map, ref_vec, roughness * RADIANCE_MAX_LOD).rgb;
specular_light = textureLod(radiance_map, ref_vec, sqrt(roughness) * RADIANCE_MAX_LOD).rgb;
specular_light = srgb_to_linear(specular_light);
specular_light *= horizon * horizon;
specular_light *= scene_data.ambient_light_color_energy.a;

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@ -1153,7 +1153,8 @@ void CopyEffects::cubemap_roughness(RID p_source_rd_texture, RID p_dest_texture,
memset(&roughness.push_constant, 0, sizeof(CubemapRoughnessPushConstant));
roughness.push_constant.face_id = p_face_id > 9 ? 0 : p_face_id;
roughness.push_constant.roughness = p_roughness * p_roughness; // Shader expects roughness, not perceptual roughness, so multiply before passing in.
// Remap to perceptual-roughness^2 to create more detail in lower mips and match the mapping of cubemap_filter.
roughness.push_constant.roughness = p_roughness * p_roughness;
roughness.push_constant.sample_count = p_sample_count;
roughness.push_constant.use_direct_write = p_roughness == 0.0;
roughness.push_constant.face_size = p_size;

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@ -70,17 +70,6 @@ float DistributionGGX(float NdotH, float roughness4) {
return roughness4 / denom;
}
// https://graphicrants.blogspot.com.au/2013/08/specular-brdf-reference.html
float GGX(float NdotV, float a) {
float k = a / 2.0;
return NdotV / (NdotV * (1.0 - k) + k);
}
// https://graphicrants.blogspot.com.au/2013/08/specular-brdf-reference.html
float G_Smith(float a, float nDotV, float nDotL) {
return GGX(nDotL, a * a) * GGX(nDotV, a * a);
}
float radicalInverse_VdC(uint bits) {
bits = (bits << 16u) | (bits >> 16u);
bits = ((bits & 0x55555555u) << 1u) | ((bits & 0xAAAAAAAAu) >> 1u);

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@ -1084,12 +1084,13 @@ void fragment_shader(in SceneData scene_data) {
#ifdef USE_RADIANCE_CUBEMAP_ARRAY
float lod, blend;
blend = modf(roughness * MAX_ROUGHNESS_LOD, lod);
blend = modf(sqrt(roughness) * MAX_ROUGHNESS_LOD, lod);
specular_light = texture(samplerCubeArray(radiance_cubemap, material_samplers[SAMPLER_LINEAR_WITH_MIPMAPS_CLAMP]), vec4(ref_vec, lod)).rgb;
specular_light = mix(specular_light, texture(samplerCubeArray(radiance_cubemap, material_samplers[SAMPLER_LINEAR_WITH_MIPMAPS_CLAMP]), vec4(ref_vec, lod + 1)).rgb, blend);
#else
specular_light = textureLod(samplerCube(radiance_cubemap, material_samplers[SAMPLER_LINEAR_WITH_MIPMAPS_CLAMP]), ref_vec, roughness * MAX_ROUGHNESS_LOD).rgb;
specular_light = textureLod(samplerCube(radiance_cubemap, material_samplers[SAMPLER_LINEAR_WITH_MIPMAPS_CLAMP]), ref_vec, sqrt(roughness) * MAX_ROUGHNESS_LOD).rgb;
#endif //USE_RADIANCE_CUBEMAP_ARRAY
specular_light *= scene_data.IBL_exposure_normalization;
@ -1137,7 +1138,7 @@ void fragment_shader(in SceneData scene_data) {
ref_vec = mix(ref_vec, n, clearcoat_roughness * clearcoat_roughness);
float horizon = min(1.0 + dot(ref_vec, normal), 1.0);
ref_vec = scene_data.radiance_inverse_xform * ref_vec;
float roughness_lod = mix(0.001, 0.1, clearcoat_roughness) * MAX_ROUGHNESS_LOD;
float roughness_lod = mix(0.001, 0.1, sqrt(clearcoat_roughness)) * MAX_ROUGHNESS_LOD;
#ifdef USE_RADIANCE_CUBEMAP_ARRAY
float lod, blend;

View file

@ -987,12 +987,12 @@ void main() {
#ifdef USE_RADIANCE_CUBEMAP_ARRAY
float lod, blend;
blend = modf(roughness * MAX_ROUGHNESS_LOD, lod);
blend = modf(sqrt(roughness) * MAX_ROUGHNESS_LOD, lod);
specular_light = texture(samplerCubeArray(radiance_cubemap, material_samplers[SAMPLER_LINEAR_WITH_MIPMAPS_CLAMP]), vec4(ref_vec, lod)).rgb;
specular_light = mix(specular_light, texture(samplerCubeArray(radiance_cubemap, material_samplers[SAMPLER_LINEAR_WITH_MIPMAPS_CLAMP]), vec4(ref_vec, lod + 1)).rgb, blend);
#else // USE_RADIANCE_CUBEMAP_ARRAY
specular_light = textureLod(samplerCube(radiance_cubemap, material_samplers[SAMPLER_LINEAR_WITH_MIPMAPS_CLAMP]), ref_vec, roughness * MAX_ROUGHNESS_LOD).rgb;
specular_light = textureLod(samplerCube(radiance_cubemap, material_samplers[SAMPLER_LINEAR_WITH_MIPMAPS_CLAMP]), ref_vec, sqrt(roughness) * MAX_ROUGHNESS_LOD).rgb;
#endif //USE_RADIANCE_CUBEMAP_ARRAY
specular_light *= sc_luminance_multiplier;
@ -1042,7 +1042,7 @@ void main() {
float horizon = min(1.0 + dot(ref_vec, normal), 1.0);
ref_vec = scene_data.radiance_inverse_xform * ref_vec;
float roughness_lod = mix(0.001, 0.1, clearcoat_roughness) * MAX_ROUGHNESS_LOD;
float roughness_lod = mix(0.001, 0.1, sqrt(clearcoat_roughness)) * MAX_ROUGHNESS_LOD;
#ifdef USE_RADIANCE_CUBEMAP_ARRAY
float lod, blend;