OpenSubdiv/opensubdiv/far/patchTables.cpp

494 lines
16 KiB
C++

//
// 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.
//
#include "../far/patchTables.h"
#include "../far/stencilTables.h"
#include <cstring>
namespace OpenSubdiv {
namespace OPENSUBDIV_VERSION {
namespace Far {
static void
getBeziereWeights(float t, float point[4], float deriv[3]) {
// The weights for the four uniform cubic Bezier basis functions are:
// (1 - t)^3
// 3 * t * (1-t)
// 3 * t^2 * (1-t)
// t^3
float t2 = t*t,
w0 = 1.0f - t,
w2 = w0 * w0;
assert(point);
point[0] = w0*w2;
point[1] = 3.0f * t * w2;
point[2] = 3.0f * t2 * w0;
point[3] = t * t2;
// The weights for the three uniform quadratic basis functions are:
// (1-t)^2
// 2 * t * (1-t)
// t^2
if (deriv) {
deriv[0] = w2;
deriv[1] = 2.0f * t * w0;
deriv[2] = t2;
}
}
static void
getBSplineWeights(float t, float point[4], float deriv[3]) {
// The weights for the four uniform cubic B-Spline basis functions are:
// (1/6)(1 - t)^3
// (1/6)(3t^3 - 6t^2 + 4)
// (1/6)(-3t^3 + 3t^2 + 3t + 1)
// (1/6)t^3
float t2 = t*t,
t3 = 3.0f*t2*t,
w0 = 1.0f-t;
assert(point);
point[0] = (w0*w0*w0) / 6.0f;
point[1] = (t3 - 6.0f*t2 + 4.0f) / 6.0f;
point[2] = (3.0f*t2 - t3 + 3.0f*t + 1.0f) / 6.0f;
point[3] = t3 / 18.0f;
// The weights for the three uniform quadratic basis functions are:
// (1/2)(1-t)^2
// (1/2)(1 + 2t - 2t^2)
// (1/2)t^2
if (deriv) {
deriv[0] = 0.5f * w0 * w0;
deriv[1] = 0.5f + t - t2;
deriv[2] = 0.5f * t2;
}
}
void
getBoxSplineWeights(float v, float w, float B[12]) {
float u = 1.0f - v - w;
//
// The 12 basis functions of the quartic box spline (unscaled by their common
// factor of 1/12 until later, and formatted to make it easy to spot any
// typing errors):
//
// 15 terms for the 3 points above the triangle corners
// 9 terms for the 3 points on faces opposite the triangle edges
// 2 terms for the 6 points on faces opposite the triangle corners
//
// Powers of each variable for notational convenience:
float u2 = u*u;
float u3 = u*u2;
float u4 = u*u3;
float v2 = v*v;
float v3 = v*v2;
float v4 = v*v3;
float w2 = w*w;
float w3 = w*w2;
float w4 = w*w3;
// And now the basis functions:
B[ 0] = u4 + 2.0f*u3*v;
B[ 1] = u4 + 2.0f*u3*w;
B[ 8] = w4 + 2.0f*w3*u;
B[11] = w4 + 2.0f*w3*v;
B[ 9] = v4 + 2.0f*v3*w;
B[ 5] = v4 + 2.0f*v3*u;
B[ 2] = u4 + 2.0f*u3*w + 6.0f*u3*v + 6.0f*u2*v*w + 12.0f*u2*v2 +
v4 + 2.0f*v3*w + 6.0f*v3*u + 6.0f*v2*u*w;
B[ 4] = w4 + 2.0f*w3*v + 6.0f*w3*u + 6.0f*w2*u*v + 12.0f*w2*u2 +
u4 + 2.0f*u3*v + 6.0f*u3*w + 6.0f*u2*v*w;
B[10] = v4 + 2.0f*v3*u + 6.0f*v3*w + 6.0f*v2*w*u + 12.0f*v2*w2 +
w4 + 2.0f*w3*u + 6.0f*w3*v + 6.0f*w3*u*v;
B[ 3] = v4 + 6*v3*w + 8*v3*u + 36*v2*w*u + 24*v2*u2 + 24*v*u3 +
w4 + 6*w3*v + 8*w3*u + 36*w2*v*u + 24*w2*u2 + 24*w*u3 + 6*u4 + 60*u2*v*w + 12*v2*w2;
B[ 6] = w4 + 6*w3*u + 8*w3*v + 36*w2*u*v + 24*w2*v2 + 24*w*v3 +
u4 + 6*u3*w + 8*u3*v + 36*u2*v*w + 24*u2*v2 + 24*u*v3 + 6*v4 + 60*v2*w*u + 12*w2*u2;
B[ 7] = u4 + 6*u3*v + 8*u3*w + 36*u2*v*w + 24*u2*w2 + 24*u*w3 +
v4 + 6*v3*u + 8*v3*w + 36*v2*u*w + 24*v2*w2 + 24*v*w3 + 6*w4 + 60*w2*u*v + 12*u2*v2;
for (int i = 0; i < 12; ++i) {
B[i] *= 1.0f / 12.0f;
}
}
void
PatchTables::getBasisWeights(TensorBasis basis, PatchParam::BitField bits,
float s, float t, float point[16], float deriv1[16], float deriv2[16]) {
int const rots[4][16] =
{ { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
{ 12, 8, 4, 0, 13, 9, 5, 1, 14, 10, 6, 2, 15, 11, 7, 3 },
{ 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 },
{ 3, 7, 11, 15, 2, 6, 10, 14, 1, 5, 9, 13, 0, 4, 8, 12 } };
assert(bits.GetRotation()<4);
int const * rot = rots[bits.GetRotation()];
float sWeights[4], tWeights[4], d1Weights[3], d2Weights[3];
if (basis==BASIS_BSPLINE) {
getBSplineWeights(s, point ? sWeights : 0, deriv1 ? d1Weights : 0);
getBSplineWeights(t, point ? tWeights : 0, deriv2 ? d2Weights : 0);
} else if (basis==BASIS_BEZIER) {
getBeziereWeights(s, point ? sWeights : 0, deriv1 ? d1Weights : 0);
getBeziereWeights(t, point ? tWeights : 0, deriv2 ? d2Weights : 0);
} else {
assert(0);
}
if (point) {
// Compute the tensor product weight corresponding to each control
// vertex
memset(point, 0, 16*sizeof(float));
for (int i = 0; i < 4; ++i) {
for (int j = 0; j < 4; ++j) {
point[rot[4*i+j]] += sWeights[j] * tWeights[i];
}
}
}
if (deriv1 and deriv2) {
// Compute the tangent stencil. This is done by taking the tensor
// product between the quadratic weights computed for s and the cubic
// weights computed for t. The stencil is constructed using
// differences between consecutive vertices in each row (i.e.
// in the s direction).
memset(deriv1, 0, 16*sizeof(float));
for (int i = 0, k = 0; i < 4; ++i) {
float prevWeight = 0.0f;
for (int j = 0; j < 3; ++j) {
float weight = d1Weights[j]*tWeights[i];
deriv1[rot[k++]] += prevWeight - weight;
prevWeight = weight;
}
deriv1[rot[k++]]+=prevWeight;
}
memset(deriv2, 0, 16*sizeof(float));
#define FASTER_TENSOR
#ifdef FASTER_TENSOR
// XXXX manuelk this might be slightly more efficient ?
float dW[4];
dW[0] = - d2Weights[0];
dW[1] = d2Weights[0] - d2Weights[1];
dW[2] = d2Weights[1] - d2Weights[2];
dW[3] = d2Weights[2];
for (int i = 0, k = 0; i < 4; ++i) {
for (int j = 0; j < 4; ++j) {
deriv2[rot[k++]] = sWeights[j] * dW[i];
}
}
#else
for (int j = 0; j < 4; ++j) {
float prevWeight = 0.0f;
for (int i = 0; i < 3; ++i) {
float weight = sWeights[j]*d2Weights[i];
deriv2[rot[4*i+j]]+=prevWeight - weight;
prevWeight = weight;
}
deriv2[rot[12+j]] += prevWeight;
}
#endif
// Scale derivatives up based on level of subdivision
float scale = float(1 << bits.GetDepth());
for (int k=0; k<16; ++k) {
deriv1[k] *= scale;
deriv2[k] *= scale;
}
}
}
PatchTables::PatchTables(int maxvalence) :
_maxValence(maxvalence), _endcapStencilTables(0), _fvarPatchTables(0) { }
// Copy constructor
// XXXX manuelk we need to eliminate this constructor (C++11 smart pointers)
PatchTables::PatchTables(PatchTables const & src) :
_maxValence(src._maxValence),
_numPtexFaces(src._numPtexFaces),
_patchArrays(src._patchArrays),
_patchVerts(src._patchVerts),
_paramTable(src._paramTable),
#ifdef ENDCAP_TOPOPOLGY
_endcapTopology(src._endcapTopology),
#endif
_quadOffsetsTable(src._quadOffsetsTable),
_vertexValenceTable(src._vertexValenceTable),
_sharpnessIndices(src._sharpnessIndices),
_sharpnessValues(src._sharpnessValues) {
_endcapStencilTables = src._endcapStencilTables ?
new StencilTables(*src._endcapStencilTables) : 0;
_fvarPatchTables = src._fvarPatchTables ?
new FVarPatchTables(*src._fvarPatchTables) : 0;
}
PatchTables::~PatchTables() {
delete _endcapStencilTables;
delete _fvarPatchTables;
}
//
// PatchArrays
//
struct PatchTables::PatchArray {
PatchArray(PatchDescriptor d, int np, Index v, Index p, Index qo) :
desc(d), numPatches(np), vertIndex(v),
patchIndex(p), quadOffsetIndex (qo) { }
PatchDescriptor desc; // type of patches in the array
int numPatches; // number of patches in the array
Index vertIndex, // index to the first control vertex
patchIndex, // index of the first patch in the array
quadOffsetIndex; // index of the first quad offset entry
};
inline PatchTables::PatchArray &
PatchTables::getPatchArray(Index arrayIndex) {
assert(arrayIndex<(Index)GetNumPatchArrays());
return _patchArrays[arrayIndex];
}
inline PatchTables::PatchArray const &
PatchTables::getPatchArray(Index arrayIndex) const {
assert(arrayIndex<(Index)GetNumPatchArrays());
return _patchArrays[arrayIndex];
}
void
PatchTables::reservePatchArrays(int numPatchArrays) {
_patchArrays.reserve(numPatchArrays);
}
inline int
getPatchSize(PatchDescriptor desc) {
int size = desc.GetNumControlVertices();
// XXXX manuelk we do not store the topology for Gregory Basis
// patch types yet - so point to the 4 corners of the 0-ring
if (desc.GetType() == PatchDescriptor::GREGORY_BASIS) {
size = 4;
}
return size;
}
void
PatchTables::pushPatchArray(PatchDescriptor desc, int npatches,
Index * vidx, Index * pidx, Index * qoidx) {
if (npatches>0) {
_patchArrays.push_back(PatchArray(
desc, npatches, *vidx, *pidx, qoidx ? *qoidx : 0));
int nverts = getPatchSize(desc);
*vidx += npatches * nverts;
*pidx += npatches;
if (qoidx) {
*qoidx += (desc.GetType() == PatchDescriptor::GREGORY) ?
npatches*nverts : 0;
}
}
}
Index *
PatchTables::getSharpnessIndices(int arrayIndex) {
return &_sharpnessIndices[getPatchArray(arrayIndex).patchIndex];
}
float *
PatchTables::getSharpnessValues(int arrayIndex) {
return &_sharpnessValues[getPatchArray(arrayIndex).patchIndex];
}
PatchDescriptor
PatchTables::GetPatchDescriptor(PatchHandle const & handle) const {
return getPatchArray(handle.arrayIndex).desc;
}
PatchDescriptor
PatchTables::GetPatchArrayDescriptor(int arrayIndex) const {
return getPatchArray(arrayIndex).desc;
}
int
PatchTables::GetNumPatchArrays() const {
return (int)_patchArrays.size();
}
int
PatchTables::GetNumPatches(int arrayIndex) const {
return getPatchArray(arrayIndex).numPatches;
}
int
PatchTables::GetNumControlVertices(int arrayIndex) const {
PatchArray const & pa = getPatchArray(arrayIndex);
return pa.numPatches * getPatchSize(pa.desc);
}
IndexArray
PatchTables::getPatchArrayVertices(int arrayIndex) {
PatchArray const & pa = getPatchArray(arrayIndex);
int size = getPatchSize(pa.desc);
assert(pa.vertIndex<(Index)_patchVerts.size());
return IndexArray(&_patchVerts[pa.vertIndex], pa.numPatches * size);
}
IndexArray const
PatchTables::GetPatchArrayVertices(int arrayIndex) const {
PatchArray const & pa = getPatchArray(arrayIndex);
int size = getPatchSize(pa.desc);
assert(pa.vertIndex<(Index)_patchVerts.size());
return IndexArray(&_patchVerts[pa.vertIndex], pa.numPatches * size);
}
IndexArray const
PatchTables::GetPatchVertices(PatchHandle const & handle) const {
PatchArray const & pa = getPatchArray(handle.arrayIndex);
Index vert = pa.vertIndex;
// XXXX manuelk we do not store the topology for Gregory Basis
// patch types yet - so point to the 4 corners of the 0-ring
vert += (pa.desc.GetType() == PatchDescriptor::GREGORY_BASIS) ?
handle.vertIndex / 5 : handle.vertIndex;
assert(vert<(Index)_patchVerts.size());
return IndexArray(&_patchVerts[vert], getPatchSize(pa.desc));
}
IndexArray const
PatchTables::GetPatchVertices(int arrayIndex, int patchIndex) const {
PatchArray const & pa = getPatchArray(arrayIndex);
int size = getPatchSize(pa.desc);
assert((pa.vertIndex + patchIndex*size)<(Index)_patchVerts.size());
return IndexArray(&_patchVerts[pa.vertIndex + patchIndex*size], size);
}
PatchParam
PatchTables::GetPatchParam(PatchHandle const & handle) const {
assert(handle.patchIndex < (Index)_paramTable.size());
return _paramTable[handle.patchIndex];
}
PatchParam
PatchTables::GetPatchParam(int arrayIndex, int patchIndex) const {
PatchArray const & pa = getPatchArray(arrayIndex);
assert((pa.patchIndex + patchIndex) < (int)_paramTable.size());
return _paramTable[pa.patchIndex + patchIndex];
}
PatchParamArray
PatchTables::getPatchParams(int arrayIndex) {
PatchArray const & pa = getPatchArray(arrayIndex);
return PatchParamArray(&_paramTable[pa.patchIndex], pa.numPatches);
}
PatchParamArray const
PatchTables::GetPatchParams(int arrayIndex) const {
PatchArray const & pa = getPatchArray(arrayIndex);
return PatchParamArray(&_paramTable[pa.patchIndex], pa.numPatches);
}
float
PatchTables::GetSingleCreasePatchSharpnessValue(PatchHandle const & handle) const {
assert((handle.patchIndex) < (int)_sharpnessIndices.size());
Index index = _sharpnessIndices[handle.patchIndex];
if (index == Vtr::INDEX_INVALID) {
return 0.0f;
}
assert(index < (Index)_sharpnessValues.size());
return _sharpnessValues[index];
}
float
PatchTables::GetSingleCreasePatchSharpnessValue(int arrayIndex, int patchIndex) const {
PatchArray const & pa = getPatchArray(arrayIndex);
assert((pa.patchIndex + patchIndex) < (int)_sharpnessIndices.size());
Index index = _sharpnessIndices[pa.patchIndex + patchIndex];
if (index == Vtr::INDEX_INVALID) {
return 0.0f;
}
assert(index < (Index)_sharpnessValues.size());
return _sharpnessValues[index];
}
PatchTables::QuadOffsetsArray const
PatchTables::GetPatchQuadOffsets(PatchHandle const & handle) const {
PatchArray const & pa = getPatchArray(handle.arrayIndex);
return Vtr::Array<unsigned int>(&_quadOffsetsTable[pa.quadOffsetIndex + handle.vertIndex], 4);
}
IndexArray
PatchTables::getFVarVerts(int arrayIndex, int channel) {
PatchArray const & pa = getPatchArray(arrayIndex);
assert(_fvarPatchTables and (channel<(int)_fvarPatchTables->_channels.size()));
std::vector<Index> & verts = _fvarPatchTables->_channels[channel].patchVertIndices;
int ofs = pa.patchIndex * pa.desc.GetNumFVarControlVertices();
return IndexArray(&verts[ofs],pa.numPatches * pa.desc.GetNumFVarControlVertices());
}
bool
PatchTables::IsFeatureAdaptive() const {
// check for presence of tables only used by adaptive patches
if (not _vertexValenceTable.empty() or _endcapStencilTables)
return true;
// otherwise, we have to check each patch array
for (int i=0; i<GetNumPatchArrays(); ++i) {
PatchDescriptor const & desc = _patchArrays[i].desc;
if (desc.GetType()>=PatchDescriptor::REGULAR and
desc.GetType()<=PatchDescriptor::GREGORY_BASIS) {
return true;
}
}
return false;
}
int
PatchTables::GetNumPatchesTotal() const {
// there is one PatchParam record for each patch in the mesh
return (int)_paramTable.size();
}
// Returns the first array of patches matching the descriptor
Index
PatchTables::findPatchArray(PatchDescriptor desc) {
for (int i=0; i<(int)_patchArrays.size(); ++i) {
if (_patchArrays[i].desc==desc)
return i;
}
return Vtr::INDEX_INVALID;
}
} // end namespace Far
} // end namespace OPENSUBDIV_VERSION
} // end namespace OpenSubdiv