implemented basic shader expressions

res/shaders/lib/BRDF.slang

@@ -20,7 +20,7 @@ struct BlinnPhong : IBRDF
         float3 h = normalize(light + view);
         float nDotH = saturate(dot(normal, h));
 		
-        return baseColor * nDotL + lightColor * specular * pow(nDotH, sheen);
+        return baseColor;
     }
 };
 

res/shaders/lib/Material.slang

@@ -6,15 +6,6 @@ interface IMaterial
 {
 	associatedtype BRDF : IBRDF;
 	BRDF prepare(MaterialFragmentParameter input);
-
-	float3 getWorldOffset();
-
-	float3 getBaseColor(MaterialFragmentParameter input);
-	float getMetallic(MaterialFragmentParameter input);
-	float3 getNormal(MaterialFragmentParameter input);
-	float getSpecular(MaterialFragmentParameter input);
-	float getRoughness(MaterialFragmentParameter input);
-	float getSheen(MaterialFragmentParameter input);
 };
 
 layout(set = INDEX_MATERIAL, binding = 0, std430)