Add metallic+gloss map

1 files changed, 14 insertions, 3 deletions

diff --git a/yum_pbr.cginc b/yum_pbr.cginc
index 93c615d..2f7113b 100644
--- a/yum_pbr.cginc
+++ b/yum_pbr.cginc
@@ -34,12 +34,23 @@ YumPbr GetYumPbr(v2f i) {
   float3x3 tangentToWorld = float3x3(i.tangent, i.binormal, i.normal);
   result.normal = normalize(mul(normal_raw, tangentToWorld));
 
-  result.smoothness = _Smoothness;
+#if defined(_METALLICS)
+  float4 metallic_gloss = tex2D(_MetallicGlossMap, UV_SCOFF(i, _MetallicGlossMap_ST, /*which_channel=*/0));
+  float metallic = metallic_gloss.r * _Metallic;
+  float smoothness = metallic_gloss.a * _Smoothness;
+
+  result.smoothness = smoothness;
   result.roughness_perceptual =
     normalFiltering(1.0 - result.smoothness, result.normal);
   result.roughness = result.roughness_perceptual * result.roughness_perceptual;
-
-  result.metallic = _Metallic;
+  result.metallic = metallic;
+#else
+  result.smoothness = 0.2;
+  result.roughness_perceptual =
+    normalFiltering(1.0 - result.smoothness, result.normal);
+  result.roughness = result.roughness_perceptual * result.roughness_perceptual;
+  result.metallic = 0;
+#endif
 
 #if defined(_AMBIENT_OCCLUSION)
   result.ao = lerp(1, tex2D(_OcclusionMap, i.uv01), _OcclusionStrength);