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OpenSubdiv/opensubdiv/vtr/level.cpp
barfowl 8cb4a1c8ad Fixed issues with refined topology not correctly oriented around vertices: 
- Refinement methods to populate relations updated to order correctly
    - updated topology validation method in Level
2014-09-23 17:37:33 -07:00

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//
// Copyright 2014 DreamWorks Animation LLC.
//
// 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 "../sdc/type.h"
#include "../sdc/crease.h"
#include "../vtr/array.h"
#include "../vtr/level.h"
#include "../vtr/refinement.h"
#include "../vtr/fvarLevel.h"
#include <cassert>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#include <map>
//
// Level:
// This is intended to be a fairly simple container of topology, sharpness and
// other information that is useful to retain for subdivision. It is intended to
// be constructed by other friend classes, i.e. factories and class specialized to
// contruct topology based on various splitting schemes. So its interface consists
// of simple methods for inspection, and low-level protected methods for populating
// it rather than high-level modifiers.
//
namespace OpenSubdiv {
namespace OPENSUBDIV_VERSION {
namespace Vtr {
//
// Simple (for now) constructor and destructor:
//
Level::Level() :
_faceCount(0),
_edgeCount(0),
_vertCount(0),
_depth(0),
_maxEdgeFaces(0),
_maxValence(0) {
}
Level::~Level() {
for (int i = 0; i < (int)_fvarChannels.size(); ++i) {
delete _fvarChannels[i];
}
}
//
// Debugging method to validate topology, i.e. verify appropriate symmetry
// between the relations, etc.
//
// Additions that need to be made in the near term:
// * verifying user-applied tags relating to topology:
// - non-manifold in particular (ordering above can be part of this)
// - face holes don't require anything
// - verifying orientation of components, particularly vert-edges and faces:
// - both need to be ordered correctly (when manifold)
// - both need to be in sync for an interior vertex
// ? is a rotation allowed for the interior case?
// - I don't see why not...
// ? verifying sharpness:
// - values < Smooth or > Infinite
// - sharpening of boundary edges (is this necessary, since we do it?)
// - it does ensure our work was not corrupted by client assignments
//
// Possibilities:
// - single validate() method, which will call all of:
// - validateTopology()
// - validateSharpness()
// - validateTagging()
// - consider using a mask/struct to choose what to validate, i.e.:
// - bool validate(ValidateOptions const& options) const;
//
bool
Level::validateTopology() const {
//
// Verify internal topological consistency (eventually a Level method?):
// - each face-vert has corresponding vert-face (and child)
// - each face-edge has corresponding edge-face
// - each edge-vert has corresponding vert-edge (and child)
// The above three are enough for most cases, but it is still possible
// the latter relation in each above has no correspondent in the former,
// so apply the symmetric tests:
// - each edge-face has corresponding face-edge
// - each vert-face has corresponding face-vert
// - each vert-edge has corresponding edge-vert
// We are still left with the possibility of duplicate references in
// places we don't want them. Currently a component can exist multiple
// times in a component of higher dimension.
// - each vert-face <face,child> pair is unique
// - each vert-edge <edge,child> pair is unique
//
bool returnOnFirstError = true;
bool isValid = true;
// Verify each face-vert has corresponding vert-face and child:
if ((getNumFaceVerticesTotal() == 0) || (getNumVertexFacesTotal() == 0)) {
if (getNumFaceVerticesTotal() == 0) printf("Error: missing face-verts\n");
if (getNumVertexFacesTotal() == 0) printf("Error: missing vert-faces\n");
return false;
}
for (int fIndex = 0; fIndex < getNumFaces(); ++fIndex) {
IndexArray const fVerts = getFaceVertices(fIndex);
int fVertCount = fVerts.size();
for (int i = 0; i < fVertCount; ++i) {
Index vIndex = fVerts[i];
IndexArray const vFaces = getVertexFaces(vIndex);
LocalIndexArray const vInFace = getVertexFaceLocalIndices(vIndex);
bool vertFaceOfFaceExists = false;
for (int j = 0; j < vFaces.size(); ++j) {
if ((vFaces[j] == fIndex) && (vInFace[j] == i)) {
vertFaceOfFaceExists = true;
break;
}
}
if (!vertFaceOfFaceExists) {
printf("Error in fIndex = %d: correlation of vert %d failed\n", fIndex, i);
if (returnOnFirstError) return false;
isValid = false;
}
}
}
// Verify each face-edge has corresponding edge-face:
if ((getNumEdgeFacesTotal() == 0) || (getNumFaceEdgesTotal() == 0)) {
if (getNumEdgeFacesTotal() == 0) printf("Error: missing edge-faces\n");
if (getNumFaceEdgesTotal() == 0) printf("Error: missing face-edges\n");
return false;
}
for (int fIndex = 0; fIndex < getNumFaces(); ++fIndex) {
IndexArray const fEdges = getFaceEdges(fIndex);
int fEdgeCount = fEdges.size();
for (int i = 0; i < fEdgeCount; ++i) {
int eIndex = fEdges[i];
IndexArray const eFaces = getEdgeFaces(eIndex);
int eFaceCount = eFaces.size();
bool edgeFaceOfFaceExists = false;
for (int j = 0; j < eFaceCount; ++j) {
if (eFaces[j] == fIndex) {
edgeFaceOfFaceExists = true;
break;
}
}
if (!edgeFaceOfFaceExists) {
printf("Error in fIndex = %d: correlation of edge %d failed\n", fIndex, i);
if (returnOnFirstError) return false;
isValid = false;
}
}
}
// Verify each edge-vert has corresponding vert-edge and child:
if ((getNumEdgeVerticesTotal() == 0) || (getNumVertexEdgesTotal() == 0)) {
if (getNumEdgeVerticesTotal() == 0) printf("Error: missing edge-verts\n");
if (getNumVertexEdgesTotal() == 0) printf("Error: missing vert-edges\n");
return false;
}
for (int eIndex = 0; eIndex < getNumEdges(); ++eIndex) {
IndexArray const eVerts = getEdgeVertices(eIndex);
for (int i = 0; i < 2; ++i) {
Index vIndex = eVerts[i];
IndexArray const vEdges = getVertexEdges(vIndex);
LocalIndexArray const vInEdge = getVertexEdgeLocalIndices(vIndex);
bool vertEdgeOfEdgeExists = false;
for (int j = 0; j < vEdges.size(); ++j) {
if ((vEdges[j] == eIndex) && (vInEdge[j] == i)) {
vertEdgeOfEdgeExists = true;
break;
}
}
if (!vertEdgeOfEdgeExists) {
printf("Error in eIndex = %d: correlation of vert %d failed\n", eIndex, i);
if (returnOnFirstError) return false;
isValid = false;
}
}
}
// Verify that vert-faces and vert-edges are properly ordered and in sync:
// - currently this requires the relations exactly match those that we construct from
// the ordering method, i.e. we do not allow rotations for interior vertices.
Index * indexBuffer = (Index*) alloca(2 * _maxValence * sizeof(Index));
for (int vIndex = 0; vIndex < getNumVertices(); ++vIndex) {
if (_vertTags[vIndex]._incomplete || _vertTags[vIndex]._nonManifold) continue;
IndexArray const vFaces = getVertexFaces(vIndex);
IndexArray const vEdges = getVertexEdges(vIndex);
Index * vFacesOrdered = indexBuffer;
Index * vEdgesOrdered = indexBuffer + vFaces.size();
if (!orderVertexFacesAndEdges(vIndex, vFacesOrdered, vEdgesOrdered)) {
printf("Error in vIndex = %d: cannot orient incident faces and edges\n", vIndex);
if (returnOnFirstError) return false;
isValid = false;
}
for (int i = 0; i < vFaces.size(); ++i) {
if (vFaces[i] != vFacesOrdered[i]) {
printf("Error in vIndex = %d: orientation failure at incident face %d\n", vIndex, i);
if (returnOnFirstError) return false;
isValid = false;
break;
}
}
for (int i = 0; i < vEdges.size(); ++i) {
if (vEdges[i] != vEdgesOrdered[i]) {
printf("Error in vIndex = %d: orientation failure at incident edge %d\n", vIndex, i);
if (returnOnFirstError) return false;
isValid = false;
break;
}
}
}
// Verify non-manifold tags are appropriately assigned to edges and vertices:
// - note we have to validate orientation of vertex neighbors to do this rigorously
for (int eIndex = 0; eIndex < getNumEdges(); ++eIndex) {
Level::ETag const& eTag = _edgeTags[eIndex];
if (eTag._nonManifold) continue;
IndexArray const eVerts = getEdgeVertices(eIndex);
if (eVerts[0] == eVerts[1]) {
printf("Error in eIndex = %d: degenerate edge not tagged marked non-manifold\n", eIndex);
if (returnOnFirstError) return false;
isValid = false;
}
IndexArray const eFaces = getEdgeFaces(eIndex);
if ((eFaces.size() < 1) || (eFaces.size() > 2)) {
printf("Error in eIndex = %d: edge with %d faces not tagged non-manifold\n", eIndex, eFaces.size());
if (returnOnFirstError) return false;
isValid = false;
}
}
return isValid;
}
//
// Anonymous helper functions for debugging output -- yes, using printf(), this is not
// intended to serve anyone other than myself for now and I favor its formatting control
//
namespace {
template <typename INT_TYPE>
void
printIndexArray(Array<INT_TYPE> const& array) {
printf("%d [%d", array.size(), array[0]);
for (int i = 1; i < array.size(); ++i) {
printf(" %d", array[i]);
}
printf("]\n");
}
const char*
ruleString(Sdc::Crease::Rule rule) {
switch (rule) {
case Sdc::Crease::RULE_UNKNOWN: return "<uninitialized>";
case Sdc::Crease::RULE_SMOOTH: return "Smooth";
case Sdc::Crease::RULE_DART: return "Dart";
case Sdc::Crease::RULE_CREASE: return "Crease";
case Sdc::Crease::RULE_CORNER: return "Corner";
default:
assert(0);
}
return 0;
}
}
void
Level::print(const Refinement* pRefinement) const {
bool printFaceVerts = true;
bool printFaceEdges = true;
bool printFaceChildVerts = false;
bool printFaceTags = true;
bool printEdgeVerts = true;
bool printEdgeFaces = true;
bool printEdgeChildVerts = true;
bool printEdgeSharpness = true;
bool printEdgeTags = true;
bool printVertFaces = true;
bool printVertEdges = true;
bool printVertChildVerts = false;
bool printVertSharpness = true;
bool printVertTags = true;
printf("Level (0x%p):\n", this);
printf(" Depth = %d\n", _depth);
printf(" Primary component counts:\n");
printf(" faces = %d\n", _faceCount);
printf(" edges = %d\n", _edgeCount);
printf(" verts = %d\n", _vertCount);
printf(" Topology relation sizes:\n");
printf(" Face relations:\n");
printf(" face-vert counts/offset = %lu\n", (unsigned long)_faceVertCountsAndOffsets.size());
printf(" face-vert indices = %lu\n", (unsigned long)_faceVertIndices.size());
for (int i = 0; printFaceVerts && i < getNumFaces(); ++i) {
printf(" face %4d verts: ", i);
printIndexArray(getFaceVertices(i));
}
printf(" face-edge indices = %lu\n", (unsigned long)_faceEdgeIndices.size());
for (int i = 0; printFaceEdges && i < getNumFaces(); ++i) {
printf(" face %4d edges: ", i);
printIndexArray(getFaceEdges(i));
}
printf(" face tags = %lu\n", (unsigned long)_faceTags.size());
for (int i = 0; printFaceTags && i < (int)_faceTags.size(); ++i) {
FTag const& fTag = _faceTags[i];
printf(" face %4d:", i);
printf(" hole = %d", (int)fTag._hole);
printf("\n");
}
if (pRefinement) {
printf(" face child-verts = %lu\n", (unsigned long)pRefinement->_faceChildVertIndex.size());
for (int i = 0; printFaceChildVerts && i < (int)pRefinement->_faceChildVertIndex.size(); ++i) {
printf(" face %4d child vert: %d\n", i, pRefinement->_faceChildVertIndex[i]);
}
}
printf(" Edge relations:\n");
printf(" edge-vert indices = %lu\n", (unsigned long)_edgeVertIndices.size());
for (int i = 0; printEdgeVerts && i < getNumEdges(); ++i) {
printf(" edge %4d verts: ", i);
printIndexArray(getEdgeVertices(i));
}
printf(" edge-face counts/offset = %lu\n", (unsigned long)_edgeFaceCountsAndOffsets.size());
printf(" edge-face indices = %lu\n", (unsigned long)_edgeFaceIndices.size());
for (int i = 0; printEdgeFaces && i < getNumEdges(); ++i) {
printf(" edge %4d faces: ", i);
printIndexArray(getEdgeFaces(i));
}
if (pRefinement) {
printf(" edge child-verts = %lu\n", (unsigned long)pRefinement->_edgeChildVertIndex.size());
for (int i = 0; printEdgeChildVerts && i < (int)pRefinement->_edgeChildVertIndex.size(); ++i) {
printf(" edge %4d child vert: %d\n", i, pRefinement->_edgeChildVertIndex[i]);
}
}
printf(" edge sharpness = %lu\n", (unsigned long)_edgeSharpness.size());
for (int i = 0; printEdgeSharpness && i < (int)_edgeSharpness.size(); ++i) {
printf(" edge %4d sharpness: %f\n", i, _edgeSharpness[i]);
}
printf(" edge tags = %lu\n", (unsigned long)_edgeTags.size());
for (int i = 0; printEdgeTags && i < (int)_edgeTags.size(); ++i) {
ETag const& eTag = _edgeTags[i];
printf(" edge %4d:", i);
printf(" boundary = %d", (int)eTag._boundary);
printf(", semiSharp = %d", (int)eTag._semiSharp);
printf(", infSharp = %d", (int)eTag._infSharp);
printf("\n");
}
printf(" Vert relations:\n");
printf(" vert-face counts/offset = %lu\n", (unsigned long)_vertFaceCountsAndOffsets.size());
printf(" vert-face indices = %lu\n", (unsigned long)_vertFaceIndices.size());
printf(" vert-face children = %lu\n", (unsigned long)_vertFaceLocalIndices.size());
for (int i = 0; printVertFaces && i < getNumVertices(); ++i) {
printf(" vert %4d faces: ", i);
printIndexArray(getVertexFaces(i));
printf(" face-verts: ");
printIndexArray(getVertexFaceLocalIndices(i));
}
printf(" vert-edge counts/offset = %lu\n", (unsigned long)_vertEdgeCountsAndOffsets.size());
printf(" vert-edge indices = %lu\n", (unsigned long)_vertEdgeIndices.size());
printf(" vert-edge children = %lu\n", (unsigned long)_vertEdgeLocalIndices.size());
for (int i = 0; printVertEdges && i < getNumVertices(); ++i) {
printf(" vert %4d edges: ", i);
printIndexArray(getVertexEdges(i));
printf(" edge-verts: ");
printIndexArray(getVertexEdgeLocalIndices(i));
}
if (pRefinement) {
printf(" vert child-verts = %lu\n", (unsigned long)pRefinement->_vertChildVertIndex.size());
for (int i = 0; printVertChildVerts && i < (int)pRefinement->_vertChildVertIndex.size(); ++i) {
printf(" vert %4d child vert: %d\n", i, pRefinement->_vertChildVertIndex[i]);
}
}
printf(" vert sharpness = %lu\n", (unsigned long)_vertSharpness.size());
for (int i = 0; printVertSharpness && i < (int)_vertSharpness.size(); ++i) {
printf(" vert %4d sharpness: %f\n", i, _vertSharpness[i]);
}
printf(" vert tags = %lu\n", (unsigned long)_vertTags.size());
for (int i = 0; printVertTags && i < (int)_vertTags.size(); ++i) {
VTag const& vTag = _vertTags[i];
printf(" vert %4d:", i);
printf(" rule = %s", ruleString((Sdc::Crease::Rule)vTag._rule));
printf(", boundary = %d", (int)vTag._boundary);
printf(", xordinary = %d", (int)vTag._xordinary);
printf(", semiSharp = %d", (int)vTag._semiSharp);
printf(", infSharp = %d", (int)vTag._infSharp);
printf("\n");
}
fflush(stdout);
}
namespace {
template <typename TAG_TYPE, typename INT_TYPE>
void
combineTags(TAG_TYPE& dstTag, TAG_TYPE const& srcTag) {
INT_TYPE const* srcInt = reinterpret_cast<INT_TYPE const*>(&srcTag);
INT_TYPE * dstInt = reinterpret_cast<INT_TYPE *> (&dstTag);
*dstInt |= *srcInt;
}
}
Level::VTag
Level::getFaceCompositeVTag(IndexArray const& faceVerts) const {
VTag compTag = _vertTags[faceVerts[0]];
for (int i = 1; i < faceVerts.size(); ++i) {
VTag const& vertTag = _vertTags[faceVerts[i]];
if (sizeof(VTag) == sizeof(unsigned short)) {
combineTags<VTag, unsigned short>(compTag, vertTag);
} else {
assert("VTag size is uint_32 -- need to adjust composite tag code..." == 0);
}
}
return compTag;
}
//
// High-level topology gathering functions -- used mainly in patch construction. These
// may eventually be moved elsewhere, possibly to classes specialized for quad- and tri-
// patch identification and construction, but for now somewhere more accessible than the
// patch tables factory is preferable.
//
// Note a couple of nuisances...
// - these are currently specialized methods for quad-meshes
// - debatable whether we should include the four face-verts in the face functions
// - we refer to the result as a "patch" when we do
// - otherwise a "ring" of vertices is more appropriate
// - some OSD containers for the results want unsigned int and others int
//
namespace {
template <typename INT_TYPE>
inline INT_TYPE fastMod4(INT_TYPE value) { return (value & 0x3); }
inline int
fastFindIn4(Index value, IndexArray const& array) {
if (value == array[0]) return 0;
if (value == array[1]) return 1;
if (value == array[2]) return 2;
if (value == array[3]) return 3;
assert("fastFindIn4() did not find expected value!" == 0);
return -1;
}
}
//
// Gathering the one-ring of vertices from quads surrounding a manifold vertex:
// - the neighborhood of the vertex is assumed to be quad-regular
//
// Ordering of resulting vertices:
// The surrounding one-ring follows the ordering of the incident faces. For each
// incident quad, the two vertices in CCW order within that quad are added. If the
// vertex is on a boundary, a third vertex on the boundary edge will be contributed from
// the last face.
//
int
Level::gatherManifoldVertexRingFromIncidentQuads(Index vIndex, int vOffset, int ringVerts[]) const {
Level const& level = *this;
IndexArray vEdges = level.getVertexEdges(vIndex);
IndexArray vFaces = level.getVertexFaces(vIndex);
LocalIndexArray vInFaces = level.getVertexFaceLocalIndices(vIndex);
bool isBoundary = (vEdges.size() > vFaces.size());
int ringIndex = 0;
for (int i = 0; i < vFaces.size(); ++i) {
//
// For every incident quad, we want the two vertices clockwise in each face, i.e.
// the vertex at the end of the leading edge and the vertex opposite this one:
//
IndexArray fVerts = level.getFaceVertices(vFaces[i]);
int vInThisFace = vInFaces[i];
ringVerts[ringIndex++] = vOffset + fVerts[fastMod4(vInThisFace + 1)];
ringVerts[ringIndex++] = vOffset + fVerts[fastMod4(vInThisFace + 2)];
if (isBoundary && (i == (vFaces.size() - 1))) {
ringVerts[ringIndex++] = vOffset + fVerts[fastMod4(vInThisFace + 3)];
}
}
return ringIndex;
}
//
// Gathering the 16 vertices of a quad-regular boundary patch:
// - the neighborhood of the face is assumed to be quad-regular
//
// Ordering of resulting vertices:
// It was debatable whether to include the vertices of the original face for a complete
// "patch" or just the surrounding ring -- clearly we ended up with a function for the entire
// patch, but that may change.
// The latter ring of vertices around the face (potentially returned on its own) was
// oriented with respect to the face. The ring of 12 vertices is gathered as 4 groups of 3
// vertices -- one for each corner vertex, and each group forming the quad opposite each
// corner vertex when combined with that corner vertex. The four vertices of the face begin
// the patch.
//
// | | | |
// ---5-----4-----15----14---
// | | | |
// | | | |
// ---6-----0-----3-----13---
// | |x x| |
// | |x x| |
// ---7-----1-----2-----12---
// | | | |
// | | | |
// ---8-----9-----10----11---
// | | | |
//
int
Level::gatherQuadRegularInteriorPatchVertices(
Index thisFace, unsigned int ringVerts[], int rotation) const {
Level const& level = *this;
//
// For each of the four corner vertices, there is a face diagonally opposite
// the given/central face, within which are three vertices of the ring:
//
IndexArray thisFaceVerts = level.getFaceVertices(thisFace);
if (rotation) {
ringVerts[0] = thisFaceVerts[fastMod4(rotation)];
ringVerts[1] = thisFaceVerts[fastMod4(rotation + 1)];
ringVerts[2] = thisFaceVerts[fastMod4(rotation + 2)];
ringVerts[3] = thisFaceVerts[fastMod4(rotation + 3)];
} else {
ringVerts[0] = thisFaceVerts[0];
ringVerts[1] = thisFaceVerts[1];
ringVerts[2] = thisFaceVerts[2];
ringVerts[3] = thisFaceVerts[3];
}
int ringIndex = 4;
for (int i = 0; i < 4; ++i) {
Index v = ringVerts[i];
IndexArray vFaces = level.getVertexFaces(v);
LocalIndexArray vInFaces = level.getVertexFaceLocalIndices(v);
int thisFaceInVFaces = fastFindIn4(thisFace, vFaces);
int intFaceInVFaces = fastMod4(thisFaceInVFaces + 2);
Index intFace = vFaces[intFaceInVFaces];
int vInIntFace = vInFaces[intFaceInVFaces];
IndexArray intFaceVerts = level.getFaceVertices(intFace);
ringVerts[ringIndex++] = intFaceVerts[fastMod4(vInIntFace + 1)];
ringVerts[ringIndex++] = intFaceVerts[fastMod4(vInIntFace + 2)];
ringVerts[ringIndex++] = intFaceVerts[fastMod4(vInIntFace + 3)];
}
assert(ringIndex == 16);
return 16;
}
//
// Gathering the 12 vertices of a quad-regular boundary patch:
// - the neighborhood of the face is assumed to be quad-regular
// - the single edge of the face that lies on the boundary is specified
// - only one edge of the face is a boundary edge
//
// Ordering of resulting vertices:
// It was debatable whether to include the vertices of the original face for a complete
// "patch" or just the surrounding ring -- clearly we ended up with a function for the entire
// patch, but that may change.
// The latter ring of vertices around the face (potentially returned on its own) was
// oriented beginning from the leading CCW boundary edge and ending at the trailing edge.
// The four vertices of the face begin the patch and are oriented similarly to this outer
// ring -- forming an inner ring that begins and ends in the same manner.
//
// ---4-----0-----3-----11---
// | |x x| |
// | |x x| |
// ---5-----1-----2-----10---
// | | | |
// | | | |
// ---6-----7-----8-----9----
// | | | |
//
int
Level::gatherQuadRegularBoundaryPatchVertices(
Index face, int unsigned ringVerts[], int boundaryEdgeInFace) const {
Level const& level = *this;
int interiorEdgeInFace = fastMod4(boundaryEdgeInFace + 2);
//
// V0 and V1 are the two interior vertices (opposite the boundary edge) around
// which we will gather most of the ring:
//
int intV0InFace = interiorEdgeInFace;
int intV1InFace = fastMod4(interiorEdgeInFace + 1);
IndexArray faceVerts = level.getFaceVertices(face);
Index v0 = faceVerts[intV0InFace];
Index v1 = faceVerts[intV1InFace];
IndexArray v0Faces = level.getVertexFaces(v0);
IndexArray v1Faces = level.getVertexFaces(v1);
LocalIndexArray v0InFaces = level.getVertexFaceLocalIndices(v0);
LocalIndexArray v1InFaces = level.getVertexFaceLocalIndices(v1);
int boundaryFaceInV0Faces = -1;
int boundaryFaceInV1Faces = -1;
for (int i = 0; i < 4; ++i) {
if (face == v0Faces[i]) boundaryFaceInV0Faces = i;
if (face == v1Faces[i]) boundaryFaceInV1Faces = i;
}
assert((boundaryFaceInV0Faces >= 0) && (boundaryFaceInV1Faces >= 0));
// Identify the four faces of interest -- previous to and opposite V0 and
// opposite and next from V1 -- relative to V0 and V1:
int prevFaceInV0Faces = fastMod4(boundaryFaceInV0Faces + 1);
int intFaceInV0Faces = fastMod4(boundaryFaceInV0Faces + 2);
int intFaceInV1Faces = fastMod4(boundaryFaceInV1Faces + 2);
int nextFaceInV1Faces = fastMod4(boundaryFaceInV1Faces + 3);
// Identify the indices of the four faces:
Index prevFace = v0Faces[prevFaceInV0Faces];
Index intV0Face = v0Faces[intFaceInV0Faces];
Index intV1Face = v1Faces[intFaceInV1Faces];
Index nextFace = v1Faces[nextFaceInV1Faces];
// Identify V0 and V1 relative to these four faces:
LocalIndex v0InPrevFace = v0InFaces[prevFaceInV0Faces];
LocalIndex v0InIntFace = v0InFaces[intFaceInV0Faces];
LocalIndex v1InIntFace = v1InFaces[intFaceInV1Faces];
LocalIndex v1InNextFace = v1InFaces[nextFaceInV1Faces];
// Access the vertices of these four faces and assign to the ring:
IndexArray prevFaceVerts = level.getFaceVertices(prevFace);
IndexArray intV0FaceVerts = level.getFaceVertices(intV0Face);
IndexArray intV1FaceVerts = level.getFaceVertices(intV1Face);
IndexArray nextFaceVerts = level.getFaceVertices(nextFace);
ringVerts[0] = faceVerts[fastMod4(boundaryEdgeInFace + 1)];
ringVerts[1] = faceVerts[fastMod4(boundaryEdgeInFace + 2)];
ringVerts[2] = faceVerts[fastMod4(boundaryEdgeInFace + 3)];
ringVerts[3] = faceVerts[ boundaryEdgeInFace];
ringVerts[4] = prevFaceVerts[fastMod4(v0InPrevFace + 2)];
ringVerts[5] = intV0FaceVerts[fastMod4(v0InIntFace + 1)];
ringVerts[6] = intV0FaceVerts[fastMod4(v0InIntFace + 2)];
ringVerts[7] = intV0FaceVerts[fastMod4(v0InIntFace + 3)];
ringVerts[8] = intV1FaceVerts[fastMod4(v1InIntFace + 1)];
ringVerts[9] = intV1FaceVerts[fastMod4(v1InIntFace + 2)];
ringVerts[10] = intV1FaceVerts[fastMod4(v1InIntFace + 3)];
ringVerts[11] = nextFaceVerts[fastMod4(v1InNextFace + 2)];
return 12;
}
//
// Gathering the 9 vertices of a quad-regular corner patch:
// - the neighborhood of the face is assumed to be quad-regular
// - the single corner vertex is specified
// - only one vertex of the face is a corner
//
// Ordering of resulting vertices:
// It was debatable whether to include the vertices of the original face for a complete
// "patch" or just the surrounding ring -- clearly we ended up with a function for the entire
// patch, but that may change.
// Like the boundary case, the latter ring of vertices around the face was oriented
// beginning from the leading CCW boundary edge and ending at the trailing edge. The four
// face vertices begin the patch, and begin with the corner vertex.
//
// 0-----3-----8---
// |x x| |
// |x x| |
// 1-----2-----7---
// | | |
// | | |
// 4-----5-----6---
// | | |
//
int
Level::gatherQuadRegularCornerPatchVertices(
Index face, unsigned int ringVerts[], int cornerVertInFace) const {
Level const& level = *this;
int interiorFaceVert = fastMod4(cornerVertInFace + 2);
IndexArray faceVerts = level.getFaceVertices(face);
Index intVert = faceVerts[interiorFaceVert];
IndexArray intVertFaces = level.getVertexFaces(intVert);
LocalIndexArray intVertInFaces = level.getVertexFaceLocalIndices(intVert);
int cornerFaceInIntVertFaces = -1;
for (int i = 0; i < intVertFaces.size(); ++i) {
if (face == intVertFaces[i]) {
cornerFaceInIntVertFaces = i;
break;
}
}
assert(cornerFaceInIntVertFaces >= 0);
// Identify the three faces relative to the interior vertex:
int prevFaceInIntVertFaces = fastMod4(cornerFaceInIntVertFaces + 1);
int intFaceInIntVertFaces = fastMod4(cornerFaceInIntVertFaces + 2);
int nextFaceInIntVertFaces = fastMod4(cornerFaceInIntVertFaces + 3);
// Identify the indices of the three other faces:
Index prevFace = intVertFaces[prevFaceInIntVertFaces];
Index intFace = intVertFaces[intFaceInIntVertFaces];
Index nextFace = intVertFaces[nextFaceInIntVertFaces];
// Identify the interior vertex relative to these three faces:
LocalIndex intVertInPrevFace = intVertInFaces[prevFaceInIntVertFaces];
LocalIndex intVertInIntFace = intVertInFaces[intFaceInIntVertFaces];
LocalIndex intVertInNextFace = intVertInFaces[nextFaceInIntVertFaces];
// Access the vertices of these three faces and assign to the ring:
IndexArray prevFaceVerts = level.getFaceVertices(prevFace);
IndexArray intFaceVerts = level.getFaceVertices(intFace);
IndexArray nextFaceVerts = level.getFaceVertices(nextFace);
ringVerts[0] = faceVerts[ cornerVertInFace];
ringVerts[1] = faceVerts[fastMod4(cornerVertInFace + 1)];
ringVerts[2] = faceVerts[fastMod4(cornerVertInFace + 2)];
ringVerts[3] = faceVerts[fastMod4(cornerVertInFace + 3)];
ringVerts[4] = prevFaceVerts[fastMod4(intVertInPrevFace + 2)];
ringVerts[5] = intFaceVerts[fastMod4(intVertInIntFace + 1)];
ringVerts[6] = intFaceVerts[fastMod4(intVertInIntFace + 2)];
ringVerts[7] = intFaceVerts[fastMod4(intVertInIntFace + 3)];
ringVerts[8] = nextFaceVerts[fastMod4(intVertInNextFace + 2)];
return 9;
}
//
// What follows is an internal/anonymous class and protected methods to complete all
// topological relations when only the face-vertex relations is defined.
//
// In keeping with the original idea that Level is just data and relies on other
// classes to construct it, this functionality may be warranted elsewhere, but we are
// collectively unclear as to where that should be at present. In the meantime, the
// implementation is provided here so that we can test and make use of it.
//
namespace {
//
// This is an internal helper class to manage the assembly of the tological relations
// that do not have a predictable size, i.e. faces-per-edge, faces-per-vertex and
// edges-per-vertex. Level manages these with two vectors:
//
// - a vector of integer pairs for the "counts" and "offsets"
// - a vector of incident members accessed by the "offset" of each
//
// The "dynamic relation" allocates the latter vector of members based on a typical
// number of members per component, e.g. we expect valence 4 vertices in a typical
// quad-mesh, and so an "expected" number might be 6 to accomodate a few x-ordinary
// vertices. The member vector is allocated with this number per component and the
// counts and offsets initialized to refer to them -- but with the counts set to 0.
// The count will be incremented as members are identified and entered, and if any
// component "overflows" the expected number of members, the members are moved to a
// separate vector in an std::map for the component.
//
// Once all incident members have been added, the main vector is compressed and may
// need to merge entries from the map in the process.
//
typedef std::map<Index, IndexVector> IrregIndexMap;
class DynamicRelation {
public:
DynamicRelation(IndexVector& countAndOffsets, IndexVector& indices, int membersPerComp);
~DynamicRelation() { }
public:
// Methods dealing with the members for each component:
IndexArray getCompMembers(Index index);
void appendCompMember(Index index, Index member);
// Methods dealing with the components:
void appendComponent();
void compressMemberIndices();
public:
int _compCount;
int _memberCountPerComp;
IndexVector & _countsAndOffsets;
IndexVector & _regIndices;
IrregIndexMap _irregIndices;
};
inline
DynamicRelation::DynamicRelation(IndexVector& countAndOffsets, IndexVector& indices, int membersPerComp) :
_compCount(0),
_memberCountPerComp(membersPerComp),
_countsAndOffsets(countAndOffsets),
_regIndices(indices) {
_compCount = (int) _countsAndOffsets.size() / 2;
for (int i = 0; i < _compCount; ++i) {
_countsAndOffsets[2*i] = 0;
_countsAndOffsets[2*i+1] = i * _memberCountPerComp;
}
_regIndices.resize(_compCount * _memberCountPerComp);
}
inline IndexArray
DynamicRelation::getCompMembers(Index compIndex) {
int count = _countsAndOffsets[2*compIndex];
if (count > _memberCountPerComp) {
IndexVector & irregMembers = _irregIndices[compIndex];
return IndexArray(&irregMembers[0], (int)irregMembers.size());
} else {
int offset = _countsAndOffsets[2*compIndex+1];
return IndexArray(&_regIndices[offset], count);
}
}
inline void
DynamicRelation::appendCompMember(Index compIndex, Index memberValue) {
int count = _countsAndOffsets[2*compIndex];
int offset = _countsAndOffsets[2*compIndex+1];
if (count < _memberCountPerComp) {
_regIndices[offset + count] = memberValue;
} else {
IndexVector& irregMembers = _irregIndices[compIndex];
if (count > _memberCountPerComp) {
irregMembers.push_back(memberValue);
} else {
irregMembers.resize(_memberCountPerComp + 1);
std::memcpy(&irregMembers[0], &_regIndices[offset], sizeof(Index) * _memberCountPerComp);
irregMembers[_memberCountPerComp] = memberValue;
}
}
_countsAndOffsets[2*compIndex] ++;
}
inline void
DynamicRelation::appendComponent() {
_countsAndOffsets.push_back(0);
_countsAndOffsets.push_back(_compCount * _memberCountPerComp);
++ _compCount;
_regIndices.resize(_compCount * _memberCountPerComp);
}
void
DynamicRelation::compressMemberIndices() {
if (_irregIndices.size() == 0) {
int memberCount = _countsAndOffsets[0];
for (int i = 1; i < _compCount; ++i) {
int count = _countsAndOffsets[2*i];
int offset = _countsAndOffsets[2*i + 1];
memmove(&_regIndices[memberCount], &_regIndices[offset], count * sizeof(Index));
_countsAndOffsets[2*i + 1] = memberCount;
memberCount += count;
}
_regIndices.resize(memberCount);
} else {
// Assign new offsets-per-component while determining if we can trivially compressed in place:
bool cannotBeCompressedInPlace = false;
int memberCount = _countsAndOffsets[0];
for (int i = 1; i < _compCount; ++i) {
_countsAndOffsets[2*i + 1] = memberCount;
cannotBeCompressedInPlace |= (memberCount > (_memberCountPerComp * i));
memberCount += _countsAndOffsets[2*i];
}
cannotBeCompressedInPlace |= (memberCount > (_memberCountPerComp * _compCount));
// Copy members into the original or temporary vector accordingly:
IndexVector tmpIndices;
if (cannotBeCompressedInPlace) {
tmpIndices.resize(memberCount);
}
IndexVector& dstIndices = cannotBeCompressedInPlace ? tmpIndices : _regIndices;
for (int i = 0; i < _compCount; ++i) {
int count = _countsAndOffsets[2*i];
Index *dstMembers = &dstIndices[_countsAndOffsets[2*i + 1]];
Index *srcMembers = (count <= _memberCountPerComp)
? &_regIndices[i * _memberCountPerComp]
: &_irregIndices[i][0];
memmove(dstMembers, srcMembers, count * sizeof(Index));
}
if (cannotBeCompressedInPlace) {
_regIndices.swap(tmpIndices);
} else {
_regIndices.resize(memberCount);
}
}
}
}
//
// Methods to populate the missing topology relations of the Level:
//
inline Index
Level::findEdge(Index v0Index, Index v1Index, IndexArray const& v0Edges) const {
if (v0Index != v1Index) {
for (int j = 0; j < v0Edges.size(); ++j) {
IndexArray eVerts = this->getEdgeVertices(v0Edges[j]);
if ((eVerts[0] == v1Index) || (eVerts[1] == v1Index)) {
return v0Edges[j];
}
}
} else {
for (int j = 0; j < v0Edges.size(); ++j) {
IndexArray eVerts = this->getEdgeVertices(v0Edges[j]);
if (eVerts[0] == eVerts[1]) {
return v0Edges[j];
}
}
}
return INDEX_INVALID;
}
Index
Level::findEdge(Index v0Index, Index v1Index) const {
return this->findEdge(v0Index, v1Index, this->getVertexEdges(v0Index));
}
void
Level::completeTopologyFromFaceVertices() {
//
// Its assumed (a pre-condition) that face-vertices have been fully specified and that we
// are to construct the remaining relations: including the edge list. We may want to
// support the existence of the edge list too in future:
//
int vCount = this->getNumVertices();
int fCount = this->getNumFaces();
int eCount = this->getNumEdges();
assert((vCount > 0) && (fCount > 0) && (eCount == 0));
// May be unnecessary depending on how the vertices and faces were defined, but worth a
// call to ensure all data related to verts and faces is available -- this will be a
// harmless call if all has been taken care of).
//
// Remember to resize edges similarly after the edge list has been assembled...
this->resizeVertices(vCount);
this->resizeFaces(fCount);
this->resizeEdges(0);
//
// Resize face-edges to match face-verts and reserve for edges based on an estimate:
//
this->_faceEdgeIndices.resize(this->getNumFaceVerticesTotal());
int eCountEstimate = (vCount << 1);
this->_edgeVertIndices.reserve(eCountEstimate * 2);
this->_edgeFaceIndices.reserve(eCountEstimate * 2);
this->_edgeFaceCountsAndOffsets.reserve(eCountEstimate * 2);
//
// Create the dynamic relations to be populated (edge-faces will remain empty as reserved
// above since there are currently no edges) and iterate through the faces to do so:
//
const int avgSize = 6;
DynamicRelation dynEdgeFaces(this->_edgeFaceCountsAndOffsets, this->_edgeFaceIndices, 2);
DynamicRelation dynVertFaces(this->_vertFaceCountsAndOffsets, this->_vertFaceIndices, avgSize);
DynamicRelation dynVertEdges(this->_vertEdgeCountsAndOffsets, this->_vertEdgeIndices, avgSize);
for (Index fIndex = 0; fIndex < fCount; ++fIndex) {
IndexArray fVerts = this->getFaceVertices(fIndex);
IndexArray fEdges = this->getFaceEdges(fIndex);
for (int i = 0; i < fVerts.size(); ++i) {
Index v0Index = fVerts[i];
Index v1Index = fVerts[(i+1) % fVerts.size()];
// Look for the edge in v0's incident edge members:
IndexArray v0Edges = dynVertEdges.getCompMembers(v0Index);
Index eIndex = this->findEdge(v0Index, v1Index, v0Edges);
// If no edge found, create/append a new one:
if (!IndexIsValid(eIndex)) {
eIndex = (Index) this->_edgeCount;
this->_edgeCount ++;
this->_edgeVertIndices.push_back(v0Index);
this->_edgeVertIndices.push_back(v1Index);
dynEdgeFaces.appendComponent();
dynVertEdges.appendCompMember(v0Index, eIndex);
dynVertEdges.appendCompMember(v1Index, eIndex);
}
dynEdgeFaces.appendCompMember(eIndex, fIndex);
dynVertFaces.appendCompMember(v0Index, fIndex);
fEdges[i] = eIndex;
}
_maxValence = std::max(_maxValence, fVerts.size());
}
dynEdgeFaces.compressMemberIndices();
dynVertFaces.compressMemberIndices();
dynVertEdges.compressMemberIndices();
//
// At this point all incident members are associated with each component. We now need
// to populate the "local indices" for each -- accounting for on-manifold potential --
// and orient each set. There is little wortwhile advantage in having the local indices
// available for the orientation as the orienting code "walks" around the components
// independent of their given order. And since determining the local indices is more
// involved for non-manifold vertices (needing to deal with repeated entries) we are
// better of orienting to determine manifold status and then computing local indices
// according to the manifold status.
//
// Resize edges with the Level to ensure anything else related to edges is created:
eCount = this->getNumEdges();
this->resizeEdges(eCount);
for (Index eIndex = 0; eIndex < eCount; ++eIndex) {
Level::ETag& eTag = this->_edgeTags[eIndex];
IndexArray eFaces = this->getEdgeFaces(eIndex);
IndexArray eVerts = this->getEdgeVertices(eIndex);
_maxEdgeFaces = std::max(_maxEdgeFaces, eFaces.size());
if ((eFaces.size() < 1) || (eFaces.size() > 2)) {
eTag._nonManifold = true;
}
if (eVerts[0] == eVerts[1]) {
printf("ASSERTION - degenerate edges not yet supported!\n");
assert(eVerts[0] != eVerts[1]);
eTag._nonManifold = true;
}
// Mark incident vertices non-manifold to avoid attempting to orient them:
if (eTag._nonManifold) {
this->_vertTags[eVerts[0]]._nonManifold = true;
this->_vertTags[eVerts[1]]._nonManifold = true;
}
}
orientIncidentComponents();
populateLocalIndices();
}
void
Level::populateLocalIndices() {
//
// We have two sets of local indices -- vert-faces and vert-edges:
//
int vCount = this->getNumVertices();
this->_vertFaceLocalIndices.resize(this->_vertFaceIndices.size());
this->_vertEdgeLocalIndices.resize(this->_vertEdgeIndices.size());
for (Index vIndex = 0; vIndex < vCount; ++vIndex) {
IndexArray vFaces = this->getVertexFaces(vIndex);
LocalIndexArray vInFaces = this->getVertexFaceLocalIndices(vIndex);
for (int i = 0; i < vFaces.size(); ++i) {
IndexArray fVerts = this->getFaceVertices(vFaces[i]);
int vInFaceIndex = (int)(std::find(fVerts.begin(), fVerts.end(), vIndex) - fVerts.begin());
vInFaces[i] = (LocalIndex) vInFaceIndex;
}
}
for (Index vIndex = 0; vIndex < vCount; ++vIndex) {
IndexArray vEdges = this->getVertexEdges(vIndex);
LocalIndexArray vInEdges = this->getVertexEdgeLocalIndices(vIndex);
for (int i = 0; i < vEdges.size(); ++i) {
IndexArray eVerts = this->getEdgeVertices(vEdges[i]);
vInEdges[i] = (vIndex == eVerts[1]);
}
_maxValence = std::max(_maxValence, vEdges.size());
}
}
void
Level::orientIncidentComponents() {
int vCount = this->getNumVertices();
for (Index vIndex = 0; vIndex < vCount; ++vIndex) {
Level::VTag vTag = this->_vertTags[vIndex];
if (!vTag._nonManifold) {
if (!orderVertexFacesAndEdges(vIndex)) {
vTag._nonManifold = true;
}
}
}
}
namespace {
inline int
findInArray(IndexArray const& array, Index value) {
return (int)(std::find(array.begin(), array.end(), value) - array.begin());
}
}
bool
Level::orderVertexFacesAndEdges(Index vIndex, Index * vFacesOrdered, Index * vEdgesOrdered) const {
IndexArray const vEdges = this->getVertexEdges(vIndex);
IndexArray const vFaces = this->getVertexFaces(vIndex);
int fCount = vFaces.size();
int eCount = vEdges.size();
if ((fCount == 0) || (eCount < 2) || ((eCount - fCount) > 1)) return false;
//
// Note we have already eliminated the possibility of incident degenerate edges
// and other bad edges earlier -- marking its vertices non-manifold as a result
// and explicitly avoiding this method:
//
Index fStart = INDEX_INVALID;
Index eStart = INDEX_INVALID;
int fvStart = 0;
if (eCount == fCount) {
// Interior case -- start with the first face
fStart = vFaces[0];
fvStart = findInArray(this->getFaceVertices(fStart), vIndex);
eStart = this->getFaceEdges(fStart)[fvStart];
} else {
// Boundary case -- start with (identify) the leading of two boundary edges:
for (int i = 0; i < eCount; ++i) {
IndexArray const eFaces = this->getEdgeFaces(vEdges[i]);
if (eFaces.size() == 1) {
eStart = vEdges[i];
fStart = eFaces[0];
fvStart = findInArray(this->getFaceVertices(fStart), vIndex);
// Singular edge -- look for forward edge to this vertex:
if (eStart == (this->getFaceEdges(fStart)[fvStart])) {
break;
}
}
}
}
//
// We have identified a starting face, face-vert and leading edge from
// which to walk counter clockwise to identify manifold neighbors. If
// this vertex is really locally manifold, we will end up back at the
// starting edge or at the other singular edge of a boundary:
//
int eCountOrdered = 1;
int fCountOrdered = 1;
vFacesOrdered[0] = fStart;
vEdgesOrdered[0] = eStart;
Index eFirst = eStart;
while (eCountOrdered < eCount) {
//
// Find the next edge, i.e. the one counter-clockwise to the last:
//
IndexArray const fVerts = this->getFaceVertices(fStart);
IndexArray const fEdges = this->getFaceEdges(fStart);
int feStart = fvStart;
int feNext = feStart ? (feStart - 1) : (fVerts.size() - 1);
Index eNext = fEdges[feNext];
// Two non-manifold situations detected:
// - two subsequent edges the same, i.e. a "repeated edge" in a face
// - back at the start before all edges processed
if ((eNext == eStart) || (eNext == eFirst)) return false;
//
// Add the next edge and if more faces to visit (not at the end of
// a boundary) look to its opposite face:
//
vEdgesOrdered[eCountOrdered++] = eNext;
if (fCountOrdered < fCount) {
IndexArray const eFaces = this->getEdgeFaces(eNext);
if (eFaces.size() == 0) return false;
if ((eFaces.size() == 1) && (eFaces[0] == fStart)) return false;
fStart = eFaces[eFaces[0] == fStart];
fvStart = findInArray(this->getFaceEdges(fStart), eNext);
vFacesOrdered[fCountOrdered++] = fStart;
}
eStart = eNext;
}
assert(eCountOrdered == eCount);
assert(fCountOrdered == fCount);
return true;
}
bool
Level::orderVertexFacesAndEdges(Index vIndex) {
IndexArray vFaces = this->getVertexFaces(vIndex);
IndexArray vEdges = this->getVertexEdges(vIndex);
Index * vFacesOrdered = (Index *)alloca((vFaces.size() + vEdges.size()) * sizeof(Index));
Index * vEdgesOrdered = vFacesOrdered + vFaces.size();
if (orderVertexFacesAndEdges(vIndex, vFacesOrdered, vEdgesOrdered)) {
std::memcpy(&vFaces[0], vFacesOrdered, vFaces.size() * sizeof(Index));
std::memcpy(&vEdges[0], vEdgesOrdered, vEdges.size() * sizeof(Index));
return true;
}
return false;
}
//
// In development -- methods for accessing face-varying data channels...
//
int
Level::createFVarChannel(int fvarValueCount, Sdc::Options const& fvarOptions) {
FVarLevel* fvarLevel = new FVarLevel(*this);
fvarLevel->setOptions(fvarOptions);
fvarLevel->resizeValues(fvarValueCount);
fvarLevel->resizeComponents();
_fvarChannels.push_back(fvarLevel);
return (int)_fvarChannels.size() - 1;
}
void
Level::destroyFVarChannel(int channel) {
delete _fvarChannels[channel];
_fvarChannels.erase(_fvarChannels.begin() + channel);
}
int
Level::getNumFVarValues(int channel) const {
return _fvarChannels[channel]->getNumValues();
}
IndexArray const
Level::getFVarFaceValues(Index faceIndex, int channel) const {
return _fvarChannels[channel]->getFaceValues(faceIndex);
}
IndexArray
Level::getFVarFaceValues(Index faceIndex, int channel) {
return _fvarChannels[channel]->getFaceValues(faceIndex);
}
void
Level::completeFVarChannelTopology(int channel) {
return _fvarChannels[channel]->completeTopologyFromFaceValues();
}
} // end namespace Vtr
} // end namespace OPENSUBDIV_VERSION
} // end namespace OpenSubdiv
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