Add horizon fading (wired off)

1 files changed, 14 insertions, 0 deletions

diff --git a/lighting.cginc b/lighting.cginc
index 9a66703..8a60e66 100755
--- a/lighting.cginc
+++ b/lighting.cginc
@@ -243,6 +243,20 @@ void GetLighting(v2f i, Pbr pbr, out LightData data) {
 #endif
   data.indirect.specular *= spec_ao;
 #endif
+
+  // Didn't see a big difference in testbed, so commented out.
+  // Bent normals get us most of what we want.
+#if 0
+  // Horizon fading
+  // https://marmosetco.tumblr.com/post/81245981087
+  // The goal is to attenuate anything which points into the mesh.
+  // TODO expose fade strength as a parameter.
+  float horizon_fade_str = 1.3;
+  float horizon_fade = saturate(1.0f + horizon_fade_str * dot(pbr.normal, -reflect_dir));
+  horizon_fade *= horizon_fade;
+  data.indirect.specular *= horizon_fade;
+#endif
+
 #if defined(_CLEARCOAT)
   data.indirect.specular_cc = getIndirectSpecular(i, saturate(sqrt(pbr.cc_roughness)), view_dir, dir_cc);
 #if defined(_CLEARCOAT_MASK)