PBR NdotV tweak

robtfm · Jan 17, 2023 · 16bc287 · 16bc287
2 parents 3774f08 + fa88d76
commit 16bc287
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Showing 2 changed files with 9 additions and 9 deletions.
diff --git a/crates/bevy_pbr/src/render/pbr_ambient.wgsl b/crates/bevy_pbr/src/render/pbr_ambient.wgsl
@@ -1,16 +1,17 @@
 #define_import_path bevy_pbr::pbr_ambient
 
+// A precomputed `NdotV` is provided because it is computed regardless,
+// but `world_normal` and the view vector `V` are provided separately for more advanced uses.
 fn ambient_light(
-    world_position: vec4<f32>, 
-    world_normal: vec3<f32>, 
-    V: vec3<f32>, 
-    diffuse_color: vec3<f32>, 
-    specular_color: vec3<f32>, 
+    world_position: vec4<f32>,
+    world_normal: vec3<f32>,
+    V: vec3<f32>,
+    NdotV: f32,
+    diffuse_color: vec3<f32>,
+    specular_color: vec3<f32>,
     perceptual_roughness: f32,
     occlusion: f32,
 ) -> vec3<f32> {
-    let NdotV = max(dot(world_normal, V), 0.0001);
-
     let diffuse_ambient = EnvBRDFApprox(diffuse_color, 1.0, NdotV);
     let specular_ambient = EnvBRDFApprox(specular_color, perceptual_roughness, NdotV);
 

diff --git a/crates/bevy_pbr/src/render/pbr_functions.wgsl b/crates/bevy_pbr/src/render/pbr_functions.wgsl
@@ -231,7 +231,7 @@ fn pbr(
         light_accum = light_accum + light_contrib * shadow;
     }
 
-    let ambient_contrib = ambient_light(in.world_position, in.N, in.V, diffuse_color, F0, perceptual_roughness, occlusion);
+    let ambient_contrib = ambient_light(in.world_position, in.N, in.V, NdotV, diffuse_color, F0, perceptual_roughness, occlusion);
 
     output_color = vec4<f32>(
         light_accum + ambient_contrib + emissive.rgb * output_color.a,
@@ -264,4 +264,3 @@ fn dither(color: vec4<f32>, pos: vec2<f32>) -> vec4<f32> {
     return vec4<f32>(color.rgb + screen_space_dither(pos.xy), color.a);
 }
 #endif
-