godot/thirdparty/embree/kernels/subdiv/half_edge.h

372 lines
13 KiB
C++

// Copyright 2009-2021 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#pragma once
#include "catmullclark_coefficients.h"
namespace embree
{
class __aligned(32) HalfEdge
{
friend class SubdivMesh;
public:
enum PatchType : char {
BILINEAR_PATCH = 0, //!< a bilinear patch
REGULAR_QUAD_PATCH = 1, //!< a regular quad patch can be represented as a B-Spline
IRREGULAR_QUAD_PATCH = 2, //!< an irregular quad patch can be represented as a Gregory patch
COMPLEX_PATCH = 3 //!< these patches need subdivision and cannot be processed by the above fast code paths
};
enum VertexType : char {
REGULAR_VERTEX = 0, //!< regular vertex
NON_MANIFOLD_EDGE_VERTEX = 1, //!< vertex of a non-manifold edge
};
__forceinline friend PatchType max( const PatchType& ty0, const PatchType& ty1) {
return (PatchType) max((int)ty0,(int)ty1);
}
struct Edge
{
/*! edge constructor */
__forceinline Edge(const uint32_t v0, const uint32_t v1)
: v0(v0), v1(v1) {}
/*! create an 64 bit identifier that is unique for the not oriented edge */
__forceinline operator uint64_t() const
{
uint32_t p0 = v0, p1 = v1;
if (p0<p1) std::swap(p0,p1);
return (((uint64_t)p0) << 32) | (uint64_t)p1;
}
public:
uint32_t v0,v1; //!< start and end vertex of the edge
};
HalfEdge ()
: vtx_index(-1), next_half_edge_ofs(0), prev_half_edge_ofs(0), opposite_half_edge_ofs(0), edge_crease_weight(0),
vertex_crease_weight(0), edge_level(0), patch_type(COMPLEX_PATCH), vertex_type(REGULAR_VERTEX)
{
static_assert(sizeof(HalfEdge) == 32, "invalid half edge size");
}
__forceinline bool hasOpposite() const { return opposite_half_edge_ofs != 0; }
__forceinline void setOpposite(HalfEdge* opposite) { opposite_half_edge_ofs = int(opposite-this); }
__forceinline HalfEdge* next() { assert( next_half_edge_ofs != 0 ); return &this[next_half_edge_ofs]; }
__forceinline const HalfEdge* next() const { assert( next_half_edge_ofs != 0 ); return &this[next_half_edge_ofs]; }
__forceinline HalfEdge* prev() { assert( prev_half_edge_ofs != 0 ); return &this[prev_half_edge_ofs]; }
__forceinline const HalfEdge* prev() const { assert( prev_half_edge_ofs != 0 ); return &this[prev_half_edge_ofs]; }
__forceinline HalfEdge* opposite() { assert( opposite_half_edge_ofs != 0 ); return &this[opposite_half_edge_ofs]; }
__forceinline const HalfEdge* opposite() const { assert( opposite_half_edge_ofs != 0 ); return &this[opposite_half_edge_ofs]; }
__forceinline HalfEdge* rotate() { return opposite()->next(); }
__forceinline const HalfEdge* rotate() const { return opposite()->next(); }
__forceinline unsigned int getStartVertexIndex() const { return vtx_index; }
__forceinline unsigned int getEndVertexIndex () const { return next()->vtx_index; }
__forceinline Edge getEdge () const { return Edge(getStartVertexIndex(),getEndVertexIndex()); }
/*! tests if the start vertex of the edge is regular */
__forceinline PatchType vertexType() const
{
const HalfEdge* p = this;
size_t face_valence = 0;
bool hasBorder = false;
do
{
/* we need subdivision to handle edge creases */
if (p->hasOpposite() && p->edge_crease_weight > 0.0f)
return COMPLEX_PATCH;
face_valence++;
/* test for quad */
const HalfEdge* pp = p;
pp = pp->next(); if (pp == p) return COMPLEX_PATCH;
pp = pp->next(); if (pp == p) return COMPLEX_PATCH;
pp = pp->next(); if (pp == p) return COMPLEX_PATCH;
pp = pp->next(); if (pp != p) return COMPLEX_PATCH;
/* continue with next face */
p = p->prev();
if (likely(p->hasOpposite()))
p = p->opposite();
/* if there is no opposite go the long way to the other side of the border */
else
{
face_valence++;
hasBorder = true;
p = this;
while (p->hasOpposite())
p = p->rotate();
}
} while (p != this);
/* calculate vertex type */
if (face_valence == 2 && hasBorder) {
if (vertex_crease_weight == 0.0f ) return REGULAR_QUAD_PATCH;
else if (vertex_crease_weight == float(inf)) return REGULAR_QUAD_PATCH;
else return COMPLEX_PATCH;
}
else if (vertex_crease_weight != 0.0f) return COMPLEX_PATCH;
else if (face_valence == 3 && hasBorder) return REGULAR_QUAD_PATCH;
else if (face_valence == 4 && !hasBorder) return REGULAR_QUAD_PATCH;
else return IRREGULAR_QUAD_PATCH;
}
/*! tests if this edge is part of a bilinear patch */
__forceinline bool bilinearVertex() const {
return vertex_crease_weight == float(inf) && edge_crease_weight == float(inf);
}
/*! calculates the type of the patch */
__forceinline PatchType patchType() const
{
const HalfEdge* p = this;
PatchType ret = REGULAR_QUAD_PATCH;
bool bilinear = true;
ret = max(ret,p->vertexType());
bilinear &= p->bilinearVertex();
if ((p = p->next()) == this) return COMPLEX_PATCH;
ret = max(ret,p->vertexType());
bilinear &= p->bilinearVertex();
if ((p = p->next()) == this) return COMPLEX_PATCH;
ret = max(ret,p->vertexType());
bilinear &= p->bilinearVertex();
if ((p = p->next()) == this) return COMPLEX_PATCH;
ret = max(ret,p->vertexType());
bilinear &= p->bilinearVertex();
if ((p = p->next()) != this) return COMPLEX_PATCH;
if (bilinear) return BILINEAR_PATCH;
return ret;
}
/*! tests if the face is a regular b-spline face */
__forceinline bool isRegularFace() const {
return patch_type == REGULAR_QUAD_PATCH;
}
/*! tests if the face can be diced (using bspline or gregory patch) */
__forceinline bool isGregoryFace() const {
return patch_type == IRREGULAR_QUAD_PATCH || patch_type == REGULAR_QUAD_PATCH;
}
/*! tests if the base vertex of this half edge is a corner vertex */
__forceinline bool isCorner() const {
return !hasOpposite() && !prev()->hasOpposite();
}
/*! tests if the vertex is attached to any border */
__forceinline bool vertexHasBorder() const
{
const HalfEdge* p = this;
do {
if (!p->hasOpposite()) return true;
p = p->rotate();
} while (p != this);
return false;
}
/*! tests if the face this half edge belongs to has some border */
__forceinline bool faceHasBorder() const
{
const HalfEdge* p = this;
do {
if (p->vertexHasBorder() && (p->vertex_type != HalfEdge::NON_MANIFOLD_EDGE_VERTEX)) return true;
p = p->next();
} while (p != this);
return false;
}
/*! calculates conservative bounds of a catmull clark subdivision face */
__forceinline BBox3fa bounds(const BufferView<Vec3fa>& vertices) const
{
BBox3fa bounds = this->get1RingBounds(vertices);
for (const HalfEdge* p=this->next(); p!=this; p=p->next())
bounds.extend(p->get1RingBounds(vertices));
return bounds;
}
/*! tests if this is a valid patch */
__forceinline bool valid(const BufferView<Vec3fa>& vertices) const
{
size_t N = 1;
if (!this->validRing(vertices)) return false;
for (const HalfEdge* p=this->next(); p!=this; p=p->next(), N++) {
if (!p->validRing(vertices)) return false;
}
return N >= 3 && N <= MAX_PATCH_VALENCE;
}
/*! counts number of polygon edges */
__forceinline unsigned int numEdges() const
{
unsigned int N = 1;
for (const HalfEdge* p=this->next(); p!=this; p=p->next(), N++);
return N;
}
/*! calculates face and edge valence */
__forceinline void calculateFaceValenceAndEdgeValence(size_t& faceValence, size_t& edgeValence) const
{
faceValence = 0;
edgeValence = 0;
const HalfEdge* p = this;
do
{
/* calculate bounds of current face */
unsigned int numEdges = p->numEdges();
assert(numEdges >= 3);
edgeValence += numEdges-2;
faceValence++;
p = p->prev();
/* continue with next face */
if (likely(p->hasOpposite()))
p = p->opposite();
/* if there is no opposite go the long way to the other side of the border */
else {
faceValence++;
edgeValence++;
p = this;
while (p->hasOpposite())
p = p->opposite()->next();
}
} while (p != this);
}
/*! stream output */
friend __forceinline std::ostream &operator<<(std::ostream &o, const HalfEdge &h)
{
return o << "{ " <<
"vertex = " << h.vtx_index << ", " << //" -> " << h.next()->vtx_index << ", " <<
"prev = " << h.prev_half_edge_ofs << ", " <<
"next = " << h.next_half_edge_ofs << ", " <<
"opposite = " << h.opposite_half_edge_ofs << ", " <<
"edge_crease = " << h.edge_crease_weight << ", " <<
"vertex_crease = " << h.vertex_crease_weight << ", " <<
//"edge_level = " << h.edge_level <<
" }";
}
private:
/*! calculates the bounds of the face associated with the half-edge */
__forceinline BBox3fa getFaceBounds(const BufferView<Vec3fa>& vertices) const
{
BBox3fa b = vertices[getStartVertexIndex()];
for (const HalfEdge* p = next(); p!=this; p=p->next()) {
b.extend(vertices[p->getStartVertexIndex()]);
}
return b;
}
/*! calculates the bounds of the 1-ring associated with the vertex of the half-edge */
__forceinline BBox3fa get1RingBounds(const BufferView<Vec3fa>& vertices) const
{
BBox3fa bounds = empty;
const HalfEdge* p = this;
do
{
/* calculate bounds of current face */
bounds.extend(p->getFaceBounds(vertices));
p = p->prev();
/* continue with next face */
if (likely(p->hasOpposite()))
p = p->opposite();
/* if there is no opposite go the long way to the other side of the border */
else {
p = this;
while (p->hasOpposite())
p = p->opposite()->next();
}
} while (p != this);
return bounds;
}
/*! tests if this is a valid face */
__forceinline bool validFace(const BufferView<Vec3fa>& vertices, size_t& N) const
{
const Vec3fa v = vertices[getStartVertexIndex()];
if (!isvalid(v)) return false;
size_t n = 1;
for (const HalfEdge* p = next(); p!=this; p=p->next(), n++) {
const Vec3fa v = vertices[p->getStartVertexIndex()];
if (!isvalid(v)) return false;
}
N += n-2;
return n >= 3 && n <= MAX_PATCH_VALENCE;
}
/*! tests if this is a valid ring */
__forceinline bool validRing(const BufferView<Vec3fa>& vertices) const
{
size_t faceValence = 0;
size_t edgeValence = 0;
const HalfEdge* p = this;
do
{
/* calculate bounds of current face */
if (!p->validFace(vertices,edgeValence))
return false;
faceValence++;
p = p->prev();
/* continue with next face */
if (likely(p->hasOpposite()))
p = p->opposite();
/* if there is no opposite go the long way to the other side of the border */
else {
faceValence++;
edgeValence++;
p = this;
while (p->hasOpposite())
p = p->opposite()->next();
}
} while (p != this);
return faceValence <= MAX_RING_FACE_VALENCE && edgeValence <= MAX_RING_EDGE_VALENCE;
}
private:
unsigned int vtx_index; //!< index of edge start vertex
int next_half_edge_ofs; //!< relative offset to next half edge of face
int prev_half_edge_ofs; //!< relative offset to previous half edge of face
int opposite_half_edge_ofs; //!< relative offset to opposite half edge
public:
float edge_crease_weight; //!< crease weight attached to edge
float vertex_crease_weight; //!< crease weight attached to start vertex
float edge_level; //!< subdivision factor for edge
PatchType patch_type; //!< stores type of subdiv patch
VertexType vertex_type; //!< stores type of the start vertex
char align[2];
};
}