OpenSubdiv/opensubdiv/osd/hlslPatchGregory.hlsl
manuelk f1518a5f59 Fix Gregory Boundary patch buffer overrun
Prevent boundaryEdgeNeighbors[2] from being overrun when an interior
vertex has more than 2 boundary neighbor vertices. The fix is applied
to the GLSL / HLSL and CPU implementations.

Note: this appears to fix long-standing problems with Gregory patches,
but i am not entirely convinced that this fixes the general case.

fixes #259
2014-02-13 11:30:33 -08:00

650 lines
23 KiB
HLSL

//
// Copyright 2013 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.
//
#if defined OSD_FRACTIONAL_ODD_SPACING
#define HS_PARTITION "fractional_odd"
#elif defined OSD_FRACTIONAL_EVEN_SPACING
#define HS_PARTITION "fractional_even"
#else
#define HS_PARTITION "integer"
#endif
//----------------------------------------------------------
// Patches.Coefficients
//----------------------------------------------------------
#if OSD_MAX_VALENCE<=10
static float ef[7] = {
0.813008, 0.500000, 0.363636, 0.287505,
0.238692, 0.204549, 0.179211
};
#else
static float ef[27] = {
0.812816, 0.500000, 0.363644, 0.287514,
0.238688, 0.204544, 0.179229, 0.159657,
0.144042, 0.131276, 0.120632, 0.111614,
0.103872, 0.09715, 0.0912559, 0.0860444,
0.0814022, 0.0772401, 0.0734867, 0.0700842,
0.0669851, 0.0641504, 0.0615475, 0.0591488,
0.0569311, 0.0548745, 0.0529621
};
#endif
float csf(uint n, uint j)
{
if (j%2 == 0) {
return cos((2.0f * M_PI * float(float(j-0)/2.0f))/(float(n)+3.0f));
} else {
return sin((2.0f * M_PI * float(float(j-1)/2.0f))/(float(n)+3.0f));
}
}
//----------------------------------------------------------
// Patches.TessVertexGregory
//----------------------------------------------------------
Buffer<float> OsdVertexBuffer : register( t0 );
Buffer<int> OsdValenceBuffer : register( t1 );
void vs_main_patches( in InputVertex input,
uint vID : SV_VertexID,
out GregHullVertex output )
{
output.hullPosition = mul(OsdModelViewMatrix(), input.position).xyz;
OSD_PATCH_CULL_COMPUTE_CLIPFLAGS(input.position);
int ivalence = OsdValenceBuffer[int(vID * (2 * OSD_MAX_VALENCE + 1))];
output.valence = ivalence;
uint valence = uint(abs(ivalence));
float3 f[OSD_MAX_VALENCE];
float3 pos = input.position.xyz;
float3 opos = float3(0,0,0);
#ifdef OSD_PATCH_GREGORY_BOUNDARY
output.org = input.position.xyz;
int boundaryEdgeNeighbors[2];
uint currNeighbor = 0;
uint ibefore = 0;
uint zerothNeighbor = 0;
#endif
for (uint i=0; i<valence; ++i) {
uint im=(i+valence-1)%valence;
uint ip=(i+1)%valence;
uint idx_neighbor = uint(OsdValenceBuffer[int(vID * (2*OSD_MAX_VALENCE+1) + 2*i + 0 + 1)]);
#ifdef OSD_PATCH_GREGORY_BOUNDARY
bool isBoundaryNeighbor = false;
int valenceNeighbor = OsdValenceBuffer[int(idx_neighbor * (2*OSD_MAX_VALENCE+1))];
if (valenceNeighbor < 0) {
isBoundaryNeighbor = true;
if (currNeighbor<2) {
boundaryEdgeNeighbors[currNeighbor] = int(idx_neighbor);
}
currNeighbor++;
if (currNeighbor == 1) {
ibefore = i;
zerothNeighbor = i;
} else {
if (i-ibefore == 1) {
int tmp = boundaryEdgeNeighbors[0];
boundaryEdgeNeighbors[0] = boundaryEdgeNeighbors[1];
boundaryEdgeNeighbors[1] = tmp;
zerothNeighbor = i;
}
}
}
#endif
float3 neighbor =
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor+2)]);
uint idx_diagonal = uint(OsdValenceBuffer[int(vID * (2*OSD_MAX_VALENCE+1) + 2*i + 1 + 1)]);
float3 diagonal =
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal+2)]);
uint idx_neighbor_p = uint(OsdValenceBuffer[int(vID * (2*OSD_MAX_VALENCE+1) + 2*ip + 0 + 1)]);
float3 neighbor_p =
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor_p)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor_p+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor_p+2)]);
uint idx_neighbor_m = uint(OsdValenceBuffer[int(vID * (2*OSD_MAX_VALENCE+1) + 2*im + 0 + 1)]);
float3 neighbor_m =
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor_m)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor_m+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor_m+2)]);
uint idx_diagonal_m = uint(OsdValenceBuffer[int(vID * (2*OSD_MAX_VALENCE+1) + 2*im + 1 + 1)]);
float3 diagonal_m =
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal_m)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal_m+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal_m+2)]);
f[i] = (pos * float(valence) + (neighbor_p + neighbor)*2.0f + diagonal) / (float(valence)+5.0f);
opos += f[i];
output.r[i] = (neighbor_p-neighbor_m)/3.0f + (diagonal - diagonal_m)/6.0f;
}
opos /= valence;
output.position = float4(opos, 1.0f).xyz;
float3 e;
output.e0 = float3(0,0,0);
output.e1 = float3(0,0,0);
for(uint i=0; i<valence; ++i) {
uint im = (i + valence -1) % valence;
e = 0.5f * (f[i] + f[im]);
output.e0 += csf(valence-3, 2*i) *e;
output.e1 += csf(valence-3, 2*i + 1)*e;
}
output.e0 *= ef[valence - 3];
output.e1 *= ef[valence - 3];
#ifdef OSD_PATCH_GREGORY_BOUNDARY
output.zerothNeighbor = zerothNeighbor;
if (currNeighbor == 1) {
boundaryEdgeNeighbors[1] = boundaryEdgeNeighbors[0];
}
if (ivalence < 0) {
if (valence > 2) {
output.position = (
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0])],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0]+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0]+2)]) +
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1])],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1]+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1]+2)]) +
4.0f * pos)/6.0f;
} else {
output.position = pos;
}
output.e0 = (
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0])],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0]+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0]+2)]) -
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1])],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1]+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1]+2)])
)/6.0;
float k = float(float(valence) - 1.0f); //k is the number of faces
float c = cos(M_PI/k);
float s = sin(M_PI/k);
float gamma = -(4.0f*s)/(3.0f*k+c);
float alpha_0k = -((1.0f+2.0f*c)*sqrt(1.0f+c))/((3.0f*k+c)*sqrt(1.0f-c));
float beta_0 = s/(3.0f*k + c);
int idx_diagonal = OsdValenceBuffer[int((vID) * (2*OSD_MAX_VALENCE+1) + 2*zerothNeighbor + 1 + 1)];
idx_diagonal = abs(idx_diagonal);
float3 diagonal =
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal+2)]);
output.e1 = gamma * pos +
alpha_0k * float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0])],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0]+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[0]+2)]) +
alpha_0k * float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1])],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1]+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*boundaryEdgeNeighbors[1]+2)]) +
beta_0 * diagonal;
for (uint x=1; x<valence - 1; ++x) {
uint curri = ((x + zerothNeighbor)%valence);
float alpha = (4.0f*sin((M_PI * float(x))/k))/(3.0f*k+c);
float beta = (sin((M_PI * float(x))/k) + sin((M_PI * float(x+1))/k))/(3.0f*k+c);
int idx_neighbor = OsdValenceBuffer[int((vID) * (2*OSD_MAX_VALENCE+1) + 2*curri + 0 + 1)];
idx_neighbor = abs(idx_neighbor);
float3 neighbor =
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_neighbor+2)]);
idx_diagonal = OsdValenceBuffer[int((vID) * (2*OSD_MAX_VALENCE+1) + 2*curri + 1 + 1)];
diagonal =
float3(OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal+1)],
OsdVertexBuffer[int(OSD_NUM_ELEMENTS*idx_diagonal+2)]);
output.e1 += alpha * neighbor + beta * diagonal;
}
output.e1 /= 3.0f;
}
#endif
}
//----------------------------------------------------------
// Patches.HullGregory
//----------------------------------------------------------
Buffer<int> OsdQuadOffsetBuffer : register( t2 );
HS_CONSTANT_FUNC_OUT HSConstFunc(
InputPatch<GregHullVertex, 4> patch,
uint primitiveID : SV_PrimitiveID)
{
HS_CONSTANT_FUNC_OUT output;
int patchLevel = GetPatchLevel(primitiveID);
OSD_PATCH_CULL(4);
#ifdef OSD_ENABLE_SCREENSPACE_TESSELLATION
output.tessLevelOuter[0] =
TessAdaptive(patch[0].hullPosition.xyz, patch[1].hullPosition.xyz);
output.tessLevelOuter[1] =
TessAdaptive(patch[0].hullPosition.xyz, patch[3].hullPosition.xyz);
output.tessLevelOuter[2] =
TessAdaptive(patch[2].hullPosition.xyz, patch[3].hullPosition.xyz);
output.tessLevelOuter[3] =
TessAdaptive(patch[1].hullPosition.xyz, patch[2].hullPosition.xyz);
output.tessLevelInner[0] =
max(output.tessLevelOuter[1], output.tessLevelOuter[3]);
output.tessLevelInner[1] =
max(output.tessLevelOuter[0], output.tessLevelOuter[2]);
#else
output.tessLevelInner[0] = GetTessLevel(patchLevel);
output.tessLevelInner[1] = GetTessLevel(patchLevel);
output.tessLevelOuter[0] = GetTessLevel(patchLevel);
output.tessLevelOuter[1] = GetTessLevel(patchLevel);
output.tessLevelOuter[2] = GetTessLevel(patchLevel);
output.tessLevelOuter[3] = GetTessLevel(patchLevel);
#endif
return output;
}
[domain("quad")]
[partitioning(HS_PARTITION)]
[outputtopology("triangle_ccw")]
[outputcontrolpoints(4)]
[patchconstantfunc("HSConstFunc")]
GregDomainVertex hs_main_patches(
in InputPatch<GregHullVertex, 4> patch,
uint primitiveID : SV_PrimitiveID,
in uint ID : SV_OutputControlPointID )
{
uint i = ID;
uint ip = (i+1)%4;
uint im = (i+3)%4;
uint valence = abs(patch[i].valence);
uint n = valence;
int base = OsdGregoryQuadOffsetBase();
GregDomainVertex output;
output.position = patch[ID].position;
uint start = uint(OsdQuadOffsetBuffer[int(4*primitiveID+base + i)]) & 0x00ffu;
uint prev = uint(OsdQuadOffsetBuffer[int(4*primitiveID+base + i)]) & 0xff00u;
prev = uint(prev/256);
uint start_m = uint(OsdQuadOffsetBuffer[int(4*primitiveID+base + im)]) & 0x00ffu;
uint prev_p = uint(OsdQuadOffsetBuffer[int(4*primitiveID+base + ip)]) & 0xff00u;
prev_p = uint(prev_p/256);
uint np = abs(patch[ip].valence);
uint nm = abs(patch[im].valence);
// Control Vertices based on :
// "Approximating Subdivision Surfaces with Gregory Patches for Hardware Tessellation"
// Loop, Schaefer, Ni, Castafio (ACM ToG Siggraph Asia 2009)
//
// P3 e3- e2+ E2
// O--------O--------O--------O
// | | | |
// | | | |
// | | f3- | f2+ |
// | O O |
// e3+ O------O O------O e2-
// | f3+ f2- |
// | |
// | |
// | f0- f1+ |
// e0- O------O O------O e1+
// | O O |
// | | f0+ | f1- |
// | | | |
// | | | |
// O--------O--------O--------O
// P0 e0+ e1- E1
//
#ifdef OSD_PATCH_GREGORY_BOUNDARY
float3 Ep = float3(0.0f,0.0f,0.0f);
float3 Em = float3(0.0f,0.0f,0.0f);
float3 Fp = float3(0.0f,0.0f,0.0f);
float3 Fm = float3(0.0f,0.0f,0.0f);
float3 Em_ip;
if (patch[ip].valence < -2) {
uint j = (np + prev_p - patch[ip].zerothNeighbor) % np;
Em_ip = patch[ip].position + cos((M_PI*j)/float(np-1))*patch[ip].e0 + sin((M_PI*j)/float(np-1))*patch[ip].e1;
} else {
Em_ip = patch[ip].position + patch[ip].e0*csf(np-3, 2*prev_p) + patch[ip].e1*csf(np-3, 2*prev_p + 1);
}
float3 Ep_im;
if (patch[im].valence < -2) {
uint j = (nm + start_m - patch[im].zerothNeighbor) % nm;
Ep_im = patch[im].position + cos((M_PI*j)/float(nm-1))*patch[im].e0 + sin((M_PI*j)/float(nm-1))*patch[im].e1;
} else {
Ep_im = patch[im].position + patch[im].e0*csf(nm-3, 2*start_m) + patch[im].e1*csf(nm-3, 2*start_m + 1);
}
if (patch[i].valence < 0) {
n = (n-1)*2;
}
if (patch[im].valence < 0) {
nm = (nm-1)*2;
}
if (patch[ip].valence < 0) {
np = (np-1)*2;
}
if (patch[i].valence > 2) {
Ep = patch[i].position + (patch[i].e0*csf(n-3, 2*start) + patch[i].e1*csf(n-3, 2*start + 1));
Em = patch[i].position + (patch[i].e0*csf(n-3, 2*prev) + patch[i].e1*csf(n-3, 2*prev + 1));
float s1=3-2*csf(n-3,2)-csf(np-3,2);
float s2=2*csf(n-3,2);
Fp = (csf(np-3,2)*patch[i].position + s1*Ep + s2*Em_ip + patch[i].r[start])/3.0f;
s1 = 3.0f-2.0f*cos(2.0f*M_PI/float(n))-cos(2.0f*M_PI/float(nm));
Fm = (csf(nm-3,2)*patch[i].position + s1*Em + s2*Ep_im - patch[i].r[prev])/3.0f;
} else if (patch[i].valence < -2) {
uint j = (valence + start - patch[i].zerothNeighbor) % valence;
Ep = patch[i].position + cos((M_PI*j)/float(valence-1))*patch[i].e0 + sin((M_PI*j)/float(valence-1))*patch[i].e1;
j = (valence + prev - patch[i].zerothNeighbor) % valence;
Em = patch[i].position + cos((M_PI*j)/float(valence-1))*patch[i].e0 + sin((M_PI*j)/float(valence-1))*patch[i].e1;
float3 Rp = ((-2.0f * patch[i].org - 1.0f * patch[im].org) + (2.0f * patch[ip].org + 1.0f * patch[(i+2)%4].org))/3.0f;
float3 Rm = ((-2.0f * patch[i].org - 1.0f * patch[ip].org) + (2.0f * patch[im].org + 1.0f * patch[(i+2)%4].org))/3.0f;
float s1 = 3-2*csf(n-3,2)-csf(np-3,2);
float s2 = 2*csf(n-3,2);
Fp = (csf(np-3,2)*patch[i].position + s1*Ep + s2*Em_ip + patch[i].r[start])/3.0f;
s1 = 3.0f-2.0f*cos(2.0f*M_PI/float(n))-cos(2.0f*M_PI/float(nm));
Fm = (csf(nm-3,2)*patch[i].position + s1*Em + s2*Ep_im - patch[i].r[prev])/3.0f;
if (patch[im].valence < 0) {
s1=3-2*csf(n-3,2)-csf(np-3,2);
Fp = Fm = (csf(np-3,2)*patch[i].position + s1*Ep + s2*Em_ip + patch[i].r[start])/3.0f;
} else if (patch[ip].valence < 0) {
s1 = 3.0f-2.0f*cos(2.0f*M_PI/n)-cos(2.0f*M_PI/nm);
Fm = Fp = (csf(nm-3,2)*patch[i].position + s1*Em + s2*Ep_im - patch[i].r[prev])/3.0f;
}
} else if (patch[i].valence == -2) {
Ep = (2.0f * patch[i].org + patch[ip].org)/3.0f;
Em = (2.0f * patch[i].org + patch[im].org)/3.0f;
Fp = Fm = (4.0f * patch[i].org + patch[(i+2)%n].org + 2.0f * patch[ip].org + 2.0f * patch[im].org)/9.0f;
}
#else // not OSD_PATCH_GREGORY_BOUNDARY
float3 Ep = patch[i].position + patch[i].e0 * csf(n-3, 2*start) + patch[i].e1*csf(n-3, 2*start + 1);
float3 Em = patch[i].position + patch[i].e0 * csf(n-3, 2*prev ) + patch[i].e1*csf(n-3, 2*prev + 1);
float3 Em_ip = patch[ip].position + patch[ip].e0*csf(np-3, 2*prev_p) + patch[ip].e1*csf(np-3, 2*prev_p + 1);
float3 Ep_im = patch[im].position + patch[im].e0*csf(nm-3, 2*start_m) + patch[im].e1*csf(nm-3, 2*start_m + 1);
float s1 = 3-2*csf(n-3,2)-csf(np-3,2);
float s2 = 2*csf(n-3,2);
float3 Fp = (csf(np-3,2)*patch[i].position + s1*Ep + s2*Em_ip + patch[i].r[start])/3.0f;
s1 = 3.0f-2.0f*cos(2.0f*M_PI/float(n))-cos(2.0f*M_PI/float(nm));
float3 Fm = (csf(nm-3,2)*patch[i].position + s1*Em +s2*Ep_im - patch[i].r[prev])/3.0f;
#endif
output.Ep = Ep;
output.Em = Em;
output.Fp = Fp;
output.Fm = Fm;
int patchLevel = GetPatchLevel(primitiveID);
output.patchCoord = float4(0, 0,
patchLevel+0.5f,
GetPrimitiveID(primitiveID)+0.5f);
OSD_COMPUTE_PTEX_COORD_HULL_SHADER;
return output;
}
//----------------------------------------------------------
// Patches.DomainGregory
//----------------------------------------------------------
[domain("quad")]
void ds_main_patches(
in HS_CONSTANT_FUNC_OUT input,
in OutputPatch<GregDomainVertex, 4> patch,
in float2 uv : SV_DomainLocation,
out OutputVertex output )
{
float u = uv.x,
v = uv.y;
float3 p[20];
p[0] = patch[0].position;
p[1] = patch[0].Ep;
p[2] = patch[0].Em;
p[3] = patch[0].Fp;
p[4] = patch[0].Fm;
p[5] = patch[1].position;
p[6] = patch[1].Ep;
p[7] = patch[1].Em;
p[8] = patch[1].Fp;
p[9] = patch[1].Fm;
p[10] = patch[2].position;
p[11] = patch[2].Ep;
p[12] = patch[2].Em;
p[13] = patch[2].Fp;
p[14] = patch[2].Fm;
p[15] = patch[3].position;
p[16] = patch[3].Ep;
p[17] = patch[3].Em;
p[18] = patch[3].Fp;
p[19] = patch[3].Fm;
float3 q[16];
float U = 1-u, V=1-v;
float d11 = u+v; if(u+v==0.0f) d11 = 1.0f;
float d12 = U+v; if(U+v==0.0f) d12 = 1.0f;
float d21 = u+V; if(u+V==0.0f) d21 = 1.0f;
float d22 = U+V; if(U+V==0.0f) d22 = 1.0f;
q[ 5] = (u*p[3] + v*p[4])/d11;
q[ 6] = (U*p[9] + v*p[8])/d12;
q[ 9] = (u*p[19] + V*p[18])/d21;
q[10] = (U*p[13] + V*p[14])/d22;
q[ 0] = p[0];
q[ 1] = p[1];
q[ 2] = p[7];
q[ 3] = p[5];
q[ 4] = p[2];
q[ 7] = p[6];
q[ 8] = p[16];
q[11] = p[12];
q[12] = p[15];
q[13] = p[17];
q[14] = p[11];
q[15] = p[10];
float3 WorldPos = float3(0, 0, 0);
float3 Tangent = float3(0, 0, 0);
float3 BiTangent = float3(0, 0, 0);
#line 519
#ifdef OSD_COMPUTE_NORMAL_DERIVATIVES
float B[4], D[4], C[4];
float3 BUCP[4], DUCP[4], CUCP[4];
float3 dUU = float3(0, 0, 0);
float3 dVV = float3(0, 0, 0);
float3 dUV = float3(0, 0, 0);
Univar4x4(u, B, D, C);
for (int i=0; i<4; ++i) {
BUCP[i] = float3(0, 0, 0);
DUCP[i] = float3(0, 0, 0);
CUCP[i] = float3(0, 0, 0);
for (uint j=0; j<4; ++j) {
// reverse face front
float3 A = q[i + 4*j];
BUCP[i] += A * B[j];
DUCP[i] += A * D[j];
CUCP[i] += A * C[j];
}
}
Univar4x4(v, B, D, C);
for (int i=0; i<4; ++i) {
WorldPos += B[i] * BUCP[i];
Tangent += B[i] * DUCP[i];
BiTangent += D[i] * BUCP[i];
dUU += B[i] * CUCP[i];
dVV += C[i] * BUCP[i];
dUV += D[i] * DUCP[i];
}
int level = int(patch[0].ptexInfo.z);
BiTangent *= 3 * level;
Tangent *= 3 * level;
dUU *= 6 * level;
dVV *= 6 * level;
dUV *= 9 * level;
float3 n = cross(Tangent, BiTangent);
float3 normal = normalize(n);
float E = dot(Tangent, Tangent);
float F = dot(Tangent, BiTangent);
float G = dot(BiTangent, BiTangent);
float e = dot(normal, dUU);
float f = dot(normal, dUV);
float g = dot(normal, dVV);
float3 Nu = (f*F-e*G)/(E*G-F*F) * Tangent + (e*F-f*E)/(E*G-F*F) * BiTangent;
float3 Nv = (g*F-f*G)/(E*G-F*F) * Tangent + (f*F-g*E)/(E*G-F*F) * BiTangent;
Nu = Nu/length(n) - n * (dot(Nu,n)/pow(dot(n,n), 1.5));
Nv = Nv/length(n) - n * (dot(Nv,n)/pow(dot(n,n), 1.5));
BiTangent = mul(OsdModelViewMatrix(), float4(BiTangent, 0)).xyz;
Tangent = mul(OsdModelViewMatrix(), float4(Tangent, 0)).xyz;
normal = normalize(cross(BiTangent, Tangent));
output.Nu = Nu;
output.Nv = Nv;
#else
float B[4], D[4];
float3 BUCP[4], DUCP[4];
Univar4x4(uv.x, B, D);
for (int i=0; i<4; ++i) {
BUCP[i] = float3(0, 0, 0);
DUCP[i] = float3(0, 0, 0);
for (uint j=0; j<4; ++j) {
// reverse face front
float3 A = q[i + 4*j];
BUCP[i] += A * B[j];
DUCP[i] += A * D[j];
}
}
Univar4x4(uv.y, B, D);
for (uint i=0; i<4; ++i) {
WorldPos += B[i] * BUCP[i];
Tangent += B[i] * DUCP[i];
BiTangent += D[i] * BUCP[i];
}
int level = int(patch[0].ptexInfo.z);
BiTangent *= 3 * level;
Tangent *= 3 * level;
BiTangent = mul(OsdModelViewMatrix(), float4(BiTangent, 0)).xyz;
Tangent = mul(OsdModelViewMatrix(), float4(Tangent, 0)).xyz;
float3 normal = normalize(cross(BiTangent, Tangent));
#endif
output.position = mul(OsdModelViewMatrix(), float4(WorldPos, 1.0f));
output.normal = normal;
output.tangent = BiTangent;
output.bitangent = Tangent;
output.patchCoord = patch[0].patchCoord;
output.patchCoord.xy = float2(v, u);
OSD_COMPUTE_PTEX_COORD_DOMAIN_SHADER;
OSD_DISPLACEMENT_CALLBACK;
output.positionOut = mul(OsdProjectionMatrix(),
float4(output.position.xyz, 1.0f));
}