implemented fragment shader parallax occlusion mapping & add some assets to test it

src/main/kotlin/CustomFloatAttribute.kt

@@ -17,5 +17,9 @@ class CustomFloatAttribute private constructor(type: Long, value: Float): FloatA
 		const val FogDensityAlias = "fogDensity"
 		val FogDensity = register(FogDensityAlias)
 		fun createFogDensity(value: Float) = CustomFloatAttribute(FogDensity, value)
+
+		const val BumpHeightAlias = "bumpHeight"
+		val BumpHeight = register(BumpHeightAlias)
+		fun createBumpHeight(value: Float) = CustomFloatAttribute(BumpHeight, value)
 	}
 }