Fix IBL DFG term

1 files changed, 5 insertions, 7 deletions

diff --git a/brdf.cginc b/brdf.cginc
index 8a3b2ff..42ab988 100755
--- a/brdf.cginc
+++ b/brdf.cginc
@@ -166,15 +166,13 @@ float4 brdf(Pbr pbr, LightData data) {
     remainder = saturate(remainder - indirect_specular_cc);
 #endif
 
-    float3 base_color = lerp(1, pbr.albedo.xyz, pbr.metallic);
-    float3 specular_dfg = lerp(dfg.xxx, dfg.yyy, f0);
-    float3 ibl_specular_reflectance = specular_dfg * base_color;
-    float3 indirect_specular = data.indirect.specular * ibl_specular_reflectance;
-
-    return float4(specular_dfg, 1);
+    float3 specular_tint = lerp(1, pbr.albedo.xyz, pbr.metallic);
+    // Filament whitepaper section 5.3.4.6
+    float3 specular_dfg = dfg.xxx * f0 + dfg.yyy;
+    float3 indirect_specular = specular_tint * data.indirect.specular * specular_dfg;
 
     specular += indirect_specular;
-    remainder = saturate(remainder - indirect_specular);
+    //remainder = saturate(remainder - indirect_specular);
 
     float3 indirect_diffuse = pbr.albedo.xyz * data.indirect.diffuse * remainder * (1.0 - pbr.metallic);
     diffuse  += indirect_diffuse;