OpenSubdiv/opensubdiv/osd/hlslPatchGregoryBasis.hlsl
David G. Yu c245407854 Re-organized patch tessellation shader code
This change refactors the GLSL and HLSL patch shader code so that
most of the work is implemented within a library of common functions
and the remaining shader snippets just manage plumbing.

There is more to do here:
  - varying and face-varying data can be managed entirely by the client
  - similarly, displacement can be implemented in client code
  - there's still quite a bit of residual boiler-plate code needed
    in each shader stage that we should be able to wrap up in a more
    convenient form.
2015-05-29 23:00:19 -07:00

130 lines
4.3 KiB
HLSL

//
// Copyright 2015 Pixar
//
// Licensed under the Apache License, Version 2.0 (the "Apache License")
// with the following modification; you may not use this file except in
// compliance with the Apache License and the following modification to it:
// Section 6. Trademarks. is deleted and replaced with:
//
// 6. Trademarks. This License does not grant permission to use the trade
// names, trademarks, service marks, or product names of the Licensor
// and its affiliates, except as required to comply with Section 4(c) of
// the License and to reproduce the content of the NOTICE file.
//
// You may obtain a copy of the Apache License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the Apache License with the above modification is
// distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the Apache License for the specific
// language governing permissions and limitations under the Apache License.
//
//----------------------------------------------------------
// Patches.VertexGregoryBasis
//----------------------------------------------------------
void vs_main_patches( in InputVertex input,
out HullVertex output )
{
output.position = input.position;
OSD_PATCH_CULL_COMPUTE_CLIPFLAGS(input.position);
}
//----------------------------------------------------------
// Patches.HullGregoryBasis
//----------------------------------------------------------
[domain("quad")]
[partitioning(OSD_PARTITIONING)]
[outputtopology("triangle_cw")]
[outputcontrolpoints(20)]
[patchconstantfunc("HSConstFunc")]
OsdPerPatchVertexGregoryBasis hs_main_patches(
in InputPatch<HullVertex, 20> patch,
uint primitiveID : SV_PrimitiveID,
in uint ID : SV_OutputControlPointID )
{
OsdPerPatchVertexGregoryBasis output;
float3 cv = patch[ID].position.xyz;
int3 patchParam = OsdGetPatchParam(OsdGetPatchIndex(primitiveID));
OsdComputePerPatchVertexGregoryBasis(patchParam, ID, cv, output);
return output;
}
HS_CONSTANT_FUNC_OUT
HSConstFunc(
InputPatch<HullVertex, 20> patch,
uint primitiveID : SV_PrimitiveID)
{
HS_CONSTANT_FUNC_OUT output;
int3 patchParam = OsdGetPatchParam(OsdGetPatchIndex(primitiveID));
float4 tessLevelOuter = float4(0,0,0,0);
float2 tessLevelInner = float2(0,0);
float4 tessOuterLo = float4(0,0,0,0);
float4 tessOuterHi = float4(0,0,0,0);
OSD_PATCH_CULL(20);
OsdGetTessLevels(patch[0].position.xyz, patch[15].position.xyz,
patch[10].position.xyz, patch[5].position.xyz,
patchParam, tessLevelOuter, tessLevelInner);
output.tessLevelOuter[0] = tessLevelOuter[0];
output.tessLevelOuter[1] = tessLevelOuter[1];
output.tessLevelOuter[2] = tessLevelOuter[2];
output.tessLevelOuter[3] = tessLevelOuter[3];
output.tessLevelInner[0] = tessLevelInner[0];
output.tessLevelInner[1] = tessLevelInner[1];
return output;
}
//----------------------------------------------------------
// Patches.DomainGregoryBasis
//----------------------------------------------------------
[domain("quad")]
void ds_main_patches(
in HS_CONSTANT_FUNC_OUT input,
in OutputPatch<OsdPerPatchVertexGregoryBasis, 20> patch,
in float2 UV : SV_DomainLocation,
out OutputVertex output )
{
float3 P = float3(0,0,0), dPu = float3(0,0,0), dPv = float3(0,0,0);
float3 N = float3(0,0,0), dNu = float3(0,0,0), dNv = float3(0,0,0);
float3 cv[20];
for (int i = 0; i < 20; ++i) {
cv[i] = patch[i].P;
}
int3 patchParam = patch[0].patchParam;
OsdEvalPatchGregory(patchParam, UV, cv, P, dPu, dPv, N, dNu, dNv);
// all code below here is client code
output.position = mul(OsdModelViewMatrix(), float4(P, 1.0f));
output.normal = mul(OsdModelViewMatrix(), float4(N, 0.0f)).xyz;
output.tangent = mul(OsdModelViewMatrix(), float4(dPu, 0.0f)).xyz;
output.bitangent = mul(OsdModelViewMatrix(), float4(dPv, 0.0f)).xyz;
#ifdef OSD_COMPUTE_NORMAL_DERIVATIVES
output.Nu = dNu;
output.Nv = dNv;
#endif
output.patchCoord = OsdInterpolatePatchCoord(UV, patchParam);
OSD_DISPLACEMENT_CALLBACK;
output.positionOut = mul(OsdProjectionMatrix(), output.position);
output.edgeDistance = 0;
}