Fix black flickering on animated models by clamping max diffuse lighting multiplier to 1.0 (#4962)

src/main/java/net/minecraftforge/client/model/pipeline/LightUtil.java

@@ -37,7 +37,7 @@ public class LightUtil
 {
     public static float diffuseLight(float x, float y, float z)
     {
-        return x * x * 0.6f + y * y * ((3f + y) / 4f) + z * z * 0.8f;
+        return Math.min(x * x * 0.6f + y * y * ((3f + y) / 4f) + z * z * 0.8f, 1f);
     }
 
     public static float diffuseLight(EnumFacing side)