#include "ShaderLibrary/PerPixelDisplacement.hlsl"
void ApplyPerPixelDisplacement(FragInputs input, float3 V, inout LayerTexCoord layerTexCoord)
float ApplyPerPixelDisplacement(FragInputs input, float3 V, inout LayerTexCoord layerTexCoord)
{
bool ppdEnable = false;
bool isPlanar = false;
float lod = ComputeTextureLOD(minUvSize);
PerPixelHeightDisplacementParam ppdParam;
float height; // final height processed
// planar/triplanar
float2 uvXZ;
if (isTriplanar)
{
float3 viewDirTS;
float planeHeight;
int numSteps;
// Perform a POM in each direction and modify appropriate texture coordinate
float2 offsetZY = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam);
float2 offsetZY = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam, planeHeight);
height = layerTexCoord.triplanarWeights.x * planeHeight;
float2 offsetXZ = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam);
float2 offsetXZ = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam, planeHeight);
height += layerTexCoord.triplanarWeights.y * planeHeight;
float2 offsetXY = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam);
float2 offsetXY = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam, planeHeight);
height += layerTexCoord.triplanarWeights.z * planeHeight;
}
else
{
float3 viewDirTS = isPlanar ? float3(uvXZ, V.y) : TransformWorldToTangent(V, worldToTangent);
int numSteps = (int)lerp(_PPDMaxSamples, _PPDMinSamples, viewDirTS.z);
float2 offset = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam);
float2 offset = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam, height);
// Since POM "pushes" geometry inwards (rather than extrude it), { height = height - 1 }.
// Since the result is used as a 'depthOffsetVS', it needs to be positive, so we flip the sign.
return maxHeight - height * maxHeight;
return 0.0;
}
// Calculate displacement for per vertex displacement mapping
GetLayerTexCoord(input, layerTexCoord);
ApplyPerPixelDisplacement(input, V, layerTexCoord);
float depthOffset = 0.0;
float depthOffset = ApplyPerPixelDisplacement(input, V, layerTexCoord);
ApplyDepthOffsetPositionInput(V, depthOffset, posInput);
ApplyDepthOffsetPositionInput(V, depthOffset, _ViewProjMatrix, posInput);
#endif
// We perform the conversion to world of the normalTS outside of the GetSurfaceData
// - Blend Mask use same mapping as main layer (UVO, Planar, Triplanar)
// From these rules it mean that PPD is enable only if the user 1) ask for it, 2) if there is one heightmap enabled on active layer, 3) if mapping is the same for all layer respecting 2), 4) if mapping is UV0, planar or triplanar mapping
// Most contraint are handled by the inspector (i.e the UI) like the mapping constraint and is assumed in the shader.
void ApplyPerPixelDisplacement(FragInputs input, float3 V, inout LayerTexCoord layerTexCoord)
float ApplyPerPixelDisplacement(FragInputs input, float3 V, inout LayerTexCoord layerTexCoord)
{
bool ppdEnable = false;
bool isPlanar = false;
ppdParam.mainHeightInfluence = 0.0;
#endif
float height; // final height processed
// We need to calculate the texture space direction. It depends on the mapping.
if (isTriplanar)
{
// TODO: do we support object triplanar ? See ComputeLayerTexCoord
float3 viewDirTS = isPlanar ? float3(-V.xz, V.y) : TransformWorldToTangent(V, worldToTangent);
int numSteps = (int)lerp(_PPDMaxSamples, _PPDMinSamples, viewDirTS.z);
float2 offset = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam);
float2 offset = ParallaxOcclusionMapping(lod, _PPDLodThreshold, numSteps, viewDirTS, maxHeight, ppdParam, height);
float4 planarWeight = float4( layerTexCoord.base0.mappingType == UV_MAPPING_PLANAR ? 1.0 : 0.0,
float4 planarWeight = float4( layerTexCoord.base0.mappingType == UV_MAPPING_PLANAR ? 1.0 : 0.0,
layerTexCoord.base1.mappingType == UV_MAPPING_PLANAR ? 1.0 : 0.0,
layerTexCoord.base2.mappingType == UV_MAPPING_PLANAR ? 1.0 : 0.0,
layerTexCoord.base3.mappingType == UV_MAPPING_PLANAR ? 1.0 : 0.0);
layerTexCoord.base0.uv += offsetWeights.x * offset;
layerTexCoord.base1.uv += offsetWeights.y * offset;
layerTexCoord.base2.uv += offsetWeights.z * offset;
layerTexCoord.details2.uv += offsetWeights.z * offset;
layerTexCoord.details3.uv += offsetWeights.w * offset;
}
// Since POM "pushes" geometry inwards (rather than extrude it), { height = height - 1 }.
// Since the result is used as a 'depthOffsetVS', it needs to be positive, so we flip the sign.
return maxHeight - height * maxHeight;
return 0.0;
}
// Calculate displacement for per vertex displacement mapping
ZERO_INITIALIZE(LayerTexCoord, layerTexCoord);
GetLayerTexCoord(input, layerTexCoord);
ApplyPerPixelDisplacement(input, V, layerTexCoord);
float depthOffset = ApplyPerPixelDisplacement(input, V, layerTexCoord);
float depthOffset = 0.0;
ApplyDepthOffsetPositionInput(V, depthOffset, posInput);
ApplyDepthOffsetPositionInput(V, depthOffset, _ViewProjMatrix, posInput);
#endif
SurfaceData surfaceData0, surfaceData1, surfaceData2, surfaceData3;
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