Merge pull request #132 from CiMaWi/dynamic-shader-triplanar-mapping

Triplanar Mapping for Projected Textures

package/Shaders/Lighting.hlsl

@@ -952,6 +952,16 @@ float GetSnowParameterY(float texProjTmp, float alpha)
 #	endif
 }
 
+float2 ComputeTriplanarUV(float3 InputPosition)
+{
+	float3 posDDX = ddx(InputPosition.xyz);
+	float3 posDDY = ddy(InputPosition.xyz);
+	return (((0.1 * (abs(posDDX.z) + abs(posDDY.z)) < abs(posDDX.x) + abs(posDDY.x)) &&
+				(0.1 * (abs(posDDX.z) + abs(posDDY.z)) < abs(posDDX.y) + abs(posDDY.y))) ?
+				InputPosition.xy :
+				((0.5 * (abs(posDDX.x) + abs(posDDY.x)) < abs(posDDX.y) + abs(posDDY.y)) ? InputPosition.yz : InputPosition.xz));
+}
+
 #	if defined(LOD)
 #		undef COMPLEX_PARALLAX_MATERIALS
 #		undef WATER_BLENDING
@@ -1149,8 +1159,13 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 
 	float2 diffuseUv = uv;
 #	if defined(SPARKLE)
+#		if defined(VR)
 	diffuseUv = ProjectedUVParams2.yy * input.TexCoord0.zw;
-#	endif  // SPARKLE
+#		else
+	float2 triplanarUv = ComputeTriplanarUV(input.InputPosition.xyz);
+	diffuseUv = ProjectedUVParams2.yy * triplanarUv;
+#		endif  // VR
+#	endif      // SPARKLE
 
 #	if defined(CPM_AVAILABLE)
 
@@ -1166,7 +1181,11 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 #		endif  // LANDSCAPE
 
 #		if defined(SPARKLE)
+#			if defined(VR)
 	diffuseUv = ProjectedUVParams2.yy * (input.TexCoord0.zw + (uv - uvOriginal));
+#			else
+	diffuseUv = ProjectedUVParams2.yy * (triplanarUv + (uv - uvOriginal));
+#			endif  // VR
 #		else
 	diffuseUv = uv;
 #		endif  // SPARKLE
@@ -1440,7 +1459,11 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 #			endif  // SNOW
 #		else
 	if (ProjectedUVParams3.w > 0.5) {
+#			if defined(VR)
+		float2 projNormalUv = ProjectedUVParams3.x * ProjectedUVParams.zz * ComputeTriplanarUV(input.InputPosition.xyz);
+#			else
 		float2 projNormalUv = ProjectedUVParams3.x * projNoiseUv;
+#			endif  // VR
 		float3 projNormal = TransformNormal(TexProjNormalSampler.Sample(SampProjNormalSampler, projNormalUv).xyz);
 		float2 projDetailUv = ProjectedUVParams3.y * projNoiseUv;
 		float3 projDetail = TexProjDetail.Sample(SampProjDetailSampler, projDetailUv).xyz;