From 4d009fee45d9a34af92391893033b8d116e2b1ea Mon Sep 17 00:00:00 2001
From: 3gg <3gg@shellblade.net>
Date: Sat, 4 Feb 2023 17:52:55 -0800
Subject: Factor out emissive term, more spec-compliant AO.
---
gfx/shaders/cook_torrance.frag | 26 ++++++++++++--------------
1 file changed, 12 insertions(+), 14 deletions(-)
diff --git a/gfx/shaders/cook_torrance.frag b/gfx/shaders/cook_torrance.frag
index fcedef6..1adb4ae 100644
--- a/gfx/shaders/cook_torrance.frag
+++ b/gfx/shaders/cook_torrance.frag
@@ -112,7 +112,7 @@ vec3 fresnel_schlick_roughness(vec3 F0, float NdotV, float roughness) {
// Cook-Torrance BRDF for a single light direction.
vec3 cook_torrance(
- vec3 albedo, float metallic, float roughness, vec3 emissive,
+ vec3 albedo, float metallic, float roughness,
float NdotL, float NdotV, float NdotH, float HdotV) {
vec3 F0 = mix(vec3(0.04), albedo, metallic);
float D = trowbridge_reitz_GGX(roughness, NdotH);
@@ -122,23 +122,20 @@ vec3 cook_torrance(
vec3 diffuse = Kd*albedo*INV_PI;
// Take a max to prevent division by 0 when either dot product is 0.
vec3 specular = (D*F*G) / max(4.0 * NdotV * NdotL, 0.0001);
- return emissive + diffuse + specular;
+ return diffuse + specular;
}
// Cook-Torrance BRDF for IBL.
vec3 cook_torrance_IBL(
- vec3 albedo, float metallic, float roughness, vec3 emissive, float occlusion,
+ vec3 albedo, float metallic, float roughness, float occlusion,
float NdotV,
- vec3 irradiance, vec3 prefiltered_env, vec2 BRDF_env, vec3 ambient) {
+ vec3 irradiance, vec3 prefiltered_env, vec2 BRDF_env) {
vec3 F0 = mix(vec3(0.04), albedo, metallic);
vec3 F = fresnel_schlick_roughness(F0, NdotV, roughness);
vec3 Kd = mix(vec3(1.0) - F, vec3(0.0), metallic);
vec3 diffuse = Kd * albedo * INV_PI * irradiance;
vec3 specular = prefiltered_env * (F * BRDF_env.x + BRDF_env.y);
- float ambient_strength = 0.05; // TODO: Make ambient strength a parameter.
- ambient *= ambient_strength * occlusion;
- emissive *= EmissiveFactor;
- return emissive + ambient + diffuse + specular;
+ return occlusion * (diffuse + specular);
}
void main()
@@ -182,30 +179,31 @@ void main()
vec2 metal_roughness = vec2(MetallicFactor, RoughnessFactor);
#endif
#ifdef HAS_EMISSIVE_MAP
- vec3 emissive = texture(EmissiveTexture, Texcoord).rgb;
+ vec3 emissive = EmissiveFactor * texture(EmissiveTexture, Texcoord).rgb;
#else
- vec3 emissive = vec3(0.0);
+ vec3 emissive = EmissiveFactor;
#endif
#ifdef HAS_OCCLUSION_MAP
float occlusion = texture(AmbientOcclusionTexture, Texcoord).r;
#else
- float occlusion = 0.0;
+ float occlusion = 1.0;
#endif
float metallic = metal_roughness.x;
float roughness = metal_roughness.y;
// For a single light direction:
- // vec3 brdf = cook_torrance(albedo, metallic, roughness, emissive, NdotL, NdotV, NdotH, HdotV);
+ // vec3 brdf = cook_torrance(albedo, metallic, roughness, NdotL, NdotV, NdotH, HdotV);
// vec3 Li = texture(Sky, N).rgb;
// vec3 colour = brdf * Li * NdotL;
// For IBL:
vec3 irradiance = texture(IrradianceMap, N).rgb;
vec3 prefiltered_env = textureLod(PrefilteredEnvironmentMap, R, roughness * MaxReflectionLOD).rgb;
- vec3 ambient = textureLod(PrefilteredEnvironmentMap, R, MaxReflectionLOD).rgb;
vec2 BRDF_env = texture(BRDFIntegrationMap, vec2(NdotV, roughness)).rg;
vec3 colour = cook_torrance_IBL(
- albedo, metallic, roughness, emissive, occlusion, NdotV, irradiance, prefiltered_env, BRDF_env, ambient);
+ albedo, metallic, roughness, occlusion, NdotV, irradiance, prefiltered_env, BRDF_env);
+
+ colour += emissive;
// Reinhard tone mapping.
colour = colour / (colour + vec3(1.0));
--
cgit v1.2.3