Rasagar/Assets/Viking Village/Boat Attack Water System/Shaders/WaterTessellation.hlsl
2024-08-26 23:07:20 +03:00

98 lines
3.3 KiB
HLSL

#ifndef WATER_TESSELLATION_INCLUDED
#define WATER_TESSELLATION_INCLUDED
///////////////////////////////////////////////////////////////////////////////
// Structs //
///////////////////////////////////////////////////////////////////////////////
struct TessellationControlPoint
{
float4 vertex : INTERNALTESSPOS;
float4 texcoord : TEXCOORD0; // Geometric UVs stored in xy, and world(pre-waves) in zw
float3 posWS : TEXCOORD1; // world position of the vertices
UNITY_VERTEX_INPUT_INSTANCE_ID
};
struct HS_ConstantOutput
{
float TessFactor[3] : SV_TessFactor;
float InsideTessFactor : SV_InsideTessFactor;
};
///////////////////////////////////////////////////////////////////////////////
// Tessellation functions //
///////////////////////////////////////////////////////////////////////////////
half _TessellationEdgeLength;
float TessellationEdgeFactor (float3 p0, float3 p1)
{
float edgeLength = distance(p0, p1);
float3 edgeCenter = (p0 + p1) * 0.5;
float viewDistance = distance(edgeCenter, _WorldSpaceCameraPos);
return edgeLength * _ScreenParams.y / (_TessellationEdgeLength * viewDistance);
}
TessellationControlPoint TessellationVertex( WaterVertexInput v )
{
TessellationControlPoint o;
o.vertex = v.vertex;
o.posWS = TransformObjectToWorld(v.vertex.xyz);
o.texcoord.xy = v.texcoord;
o.texcoord.zw = o.posWS.xz;
//o.color = v.color;
return o;
}
HS_ConstantOutput HSConstant( InputPatch<TessellationControlPoint, 3> Input )
{
float3 p0 = TransformObjectToWorld(Input[0].vertex.xyz);
float3 p1 = TransformObjectToWorld(Input[1].vertex.xyz);
float3 p2 = TransformObjectToWorld(Input[2].vertex.xyz);
HS_ConstantOutput o = (HS_ConstantOutput)0;
o.TessFactor[0] = TessellationEdgeFactor(p1, p2);
o.TessFactor[1] = TessellationEdgeFactor(p2, p0);
o.TessFactor[2] = TessellationEdgeFactor(p0, p1);
o.InsideTessFactor = (TessellationEdgeFactor(p1, p2) +
TessellationEdgeFactor(p2, p0) +
TessellationEdgeFactor(p0, p1)) * (1 / 3.0);
return o;
}
[domain("tri")]
[partitioning("fractional_odd")]
[outputtopology("triangle_cw")]
[patchconstantfunc("HSConstant")]
[outputcontrolpoints(3)]
TessellationControlPoint Hull( InputPatch<TessellationControlPoint, 3> Input, uint uCPID : SV_OutputControlPointID )
{
return Input[uCPID];
}
// Domain: replaces vert for tessellation version
[domain("tri")]
WaterVertexOutput Domain( HS_ConstantOutput HSConstantData, const OutputPatch<TessellationControlPoint, 3> Input, float3 BarycentricCoords : SV_DomainLocation)
{
WaterVertexOutput o = (WaterVertexOutput)0;
UNITY_SETUP_INSTANCE_ID(v);
UNITY_TRANSFER_INSTANCE_ID(v, o);
UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
/////////////////////Tessellation////////////////////////
float fU = BarycentricCoords.x;
float fV = BarycentricCoords.y;
float fW = BarycentricCoords.z;
float4 vertex = Input[0].vertex * fU + Input[1].vertex * fV + Input[2].vertex * fW;
o.uv = Input[0].texcoord * fU + Input[1].texcoord * fV + Input[2].texcoord * fW;
o.posWS = Input[0].posWS * fU + Input[1].posWS * fV + Input[2].posWS * fW;
o = WaveVertexOperations(o);
return o;
}
#endif // WATER_TESSELLATION_INCLUDED