OpenSubdiv/opensubdiv/hbr/subdivision.h
jcowles 392e5e8bed Remove #pragma once
While this may be worth revisiting, we should first quantify the benefits and
identify the compilers that support it. Ultimately, we may never use pragma
once in favor of strictly using standard C++.
2015-05-20 09:59:18 -07:00

294 lines
11 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.
//
#ifndef OPENSUBDIV3_HBRSUBDIVISION_H
#define OPENSUBDIV3_HBRSUBDIVISION_H
#include "../version.h"
namespace OpenSubdiv {
namespace OPENSUBDIV_VERSION {
template <class T> class HbrFace;
template <class T> class HbrVertex;
template <class T> class HbrHalfedge;
template <class T> class HbrMesh;
template <class T> class HbrSubdivision {
public:
HbrSubdivision<T>()
: creaseSubdivision(k_CreaseNormal) {}
virtual ~HbrSubdivision<T>() {}
virtual HbrSubdivision<T>* Clone() const = 0;
// How to subdivide a face
virtual void Refine(HbrMesh<T>* mesh, HbrFace<T>* face) = 0;
// Subdivide a face only at a particular vertex (creating one child)
virtual HbrFace<T>* RefineFaceAtVertex(HbrMesh<T>* mesh, HbrFace<T>* face, HbrVertex<T>* vertex) = 0;
// Refine all faces around a particular vertex
virtual void RefineAtVertex(HbrMesh<T>* mesh, HbrVertex<T>* vertex);
// Given an edge, try to ensure the edge's opposite exists by
// forcing refinement up the hierarchy
virtual void GuaranteeNeighbor(HbrMesh<T>* mesh, HbrHalfedge<T>* edge) = 0;
// Given an vertex, ensure all faces in the ring around it exist
// by forcing refinement up the hierarchy
virtual void GuaranteeNeighbors(HbrMesh<T>* mesh, HbrVertex<T>* vertex) = 0;
// Returns true if the vertex, edge, or face has a limit point,
// curve, or surface associated with it
virtual bool HasLimit(HbrMesh<T>* /* mesh */, HbrFace<T>* /* face */) { return true; }
virtual bool HasLimit(HbrMesh<T>* /* mesh */, HbrHalfedge<T>* /* edge */) { return true; }
virtual bool HasLimit(HbrMesh<T>* /* mesh */, HbrVertex<T>* /* vertex */) { return true; }
// How to turn faces, edges, and vertices into vertices
virtual HbrVertex<T>* Subdivide(HbrMesh<T>* mesh, HbrFace<T>* face) = 0;
virtual HbrVertex<T>* Subdivide(HbrMesh<T>* mesh, HbrHalfedge<T>* edge) = 0;
virtual HbrVertex<T>* Subdivide(HbrMesh<T>* mesh, HbrVertex<T>* vertex) = 0;
// Returns true if the vertex is extraordinary in the subdivision scheme
virtual bool VertexIsExtraordinary(HbrMesh<T> const * /* mesh */, HbrVertex<T>* /* vertex */) { return false; }
// Returns true if the face is extraordinary in the subdivision scheme
virtual bool FaceIsExtraordinary(HbrMesh<T> const * /* mesh */, HbrFace<T>* /* face */) { return false; }
// Crease subdivision rules. When subdividing a edge with a crease
// strength, we get two child subedges, and we need to determine
// what weights to assign these subedges. The "normal" rule
// is to simply assign the current edge's crease strength - 1
// to both of the child subedges. The "Chaikin" rule looks at the
// current edge and incident edges to the current edge's end
// vertices, and weighs them; for more information consult
// the Geri's Game paper.
enum CreaseSubdivision {
k_CreaseNormal,
k_CreaseChaikin
};
CreaseSubdivision GetCreaseSubdivisionMethod() const { return creaseSubdivision; }
void SetCreaseSubdivisionMethod(CreaseSubdivision method) { creaseSubdivision = method; }
// Figures out how to assign a crease weight on an edge to its
// subedge. The subedge must be a child of the parent edge
// (either subedge->GetOrgVertex() or subedge->GetDestVertex()
// == edge->Subdivide()). The vertex supplied must NOT be
// a parent of the subedge; it is either the origin or
// destination vertex of edge.
void SubdivideCreaseWeight(HbrHalfedge<T>* edge, HbrVertex<T>* vertex, HbrHalfedge<T>* subedge);
// Returns the expected number of children faces after subdivision
// for a face with the given number of vertices.
virtual int GetFaceChildrenCount(int nvertices) const = 0;
protected:
CreaseSubdivision creaseSubdivision;
// Helper routine for subclasses: for a given vertex, sums
// contributions from surrounding vertices
void AddSurroundingVerticesWithWeight(HbrMesh<T>* mesh, HbrVertex<T>* vertex, float weight, T* data);
// Helper routine for subclasses: for a given vertex with a crease
// mask, adds contributions from the two crease edges
void AddCreaseEdgesWithWeight(HbrMesh<T>* mesh, HbrVertex<T>* vertex, bool next, float weight, T* data);
private:
// Helper class used by AddSurroundingVerticesWithWeight
class SmoothSubdivisionVertexOperator : public HbrVertexOperator<T> {
public:
SmoothSubdivisionVertexOperator(T* data, bool meshHasEdits, float weight)
: m_data(data),
m_meshHasEdits(meshHasEdits),
m_weight(weight)
{
}
virtual void operator() (HbrVertex<T> &vertex) {
// Must ensure vertex edits have been applied
if (m_meshHasEdits) {
vertex.GuaranteeNeighbors();
}
m_data->AddWithWeight(vertex.GetData(), m_weight);
}
private:
T* m_data;
const bool m_meshHasEdits;
const float m_weight;
};
// Helper class used by AddCreaseEdgesWithWeight
class CreaseSubdivisionHalfedgeOperator : public HbrHalfedgeOperator<T> {
public:
CreaseSubdivisionHalfedgeOperator(HbrVertex<T> *vertex, T* data, bool meshHasEdits, bool next, float weight)
: m_vertex(vertex),
m_data(data),
m_meshHasEdits(meshHasEdits),
m_next(next),
m_weight(weight),
m_count(0)
{
}
virtual void operator() (HbrHalfedge<T> &edge) {
if (m_count < 2 && edge.IsSharp(m_next)) {
HbrVertex<T>* a = edge.GetDestVertex();
if (a == m_vertex) a = edge.GetOrgVertex();
// Must ensure vertex edits have been applied
if (m_meshHasEdits) {
a->GuaranteeNeighbors();
}
m_data->AddWithWeight(a->GetData(), m_weight);
m_count++;
}
}
private:
HbrVertex<T>* m_vertex;
T* m_data;
const bool m_meshHasEdits;
const bool m_next;
const float m_weight;
int m_count;
};
private:
// Helper class used by RefineAtVertex.
class RefineFaceAtVertexOperator : public HbrFaceOperator<T> {
public:
RefineFaceAtVertexOperator(HbrSubdivision<T>* subdivision, HbrMesh<T>* mesh, HbrVertex<T> *vertex)
: m_subdivision(subdivision),
m_mesh(mesh),
m_vertex(vertex)
{
}
virtual void operator() (HbrFace<T> &face) {
m_subdivision->RefineFaceAtVertex(m_mesh, &face, m_vertex);
}
private:
HbrSubdivision<T>* const m_subdivision;
HbrMesh<T>* const m_mesh;
HbrVertex<T>* const m_vertex;
};
};
template <class T>
void
HbrSubdivision<T>::RefineAtVertex(HbrMesh<T>* mesh, HbrVertex<T>* vertex) {
GuaranteeNeighbors(mesh, vertex);
RefineFaceAtVertexOperator op(this, mesh, vertex);
vertex->ApplyOperatorSurroundingFaces(op);
}
template <class T>
void
HbrSubdivision<T>::SubdivideCreaseWeight(HbrHalfedge<T>* edge, HbrVertex<T>* vertex, HbrHalfedge<T>* subedge) {
float sharpness = edge->GetSharpness();
// In all methods, if the parent edge is infinitely sharp, the
// child edge is also infinitely sharp
if (sharpness >= HbrHalfedge<T>::k_InfinitelySharp) {
subedge->SetSharpness(HbrHalfedge<T>::k_InfinitelySharp);
}
// Chaikin's curve subdivision: use 3/4 of the parent sharpness,
// plus 1/4 of crease sharpnesses incident to vertex
else if (creaseSubdivision == HbrSubdivision<T>::k_CreaseChaikin) {
float childsharp = 0.0f;
int n = 0;
// Add 1/4 of the sharpness of all crease edges incident to
// the vertex (other than this crease edge)
class ChaikinEdgeCreaseOperator : public HbrHalfedgeOperator<T> {
public:
ChaikinEdgeCreaseOperator(
HbrHalfedge<T> const * edge, float & childsharp, int & count) :
m_edge(edge), m_childsharp(childsharp), m_count(count) { }
virtual void operator() (HbrHalfedge<T> &edge) {
// Skip original edge or it's opposite
if ((&edge==m_edge) || (&edge==m_edge->GetOpposite()))
return;
if (edge.GetSharpness() > HbrHalfedge<T>::k_Smooth) {
m_childsharp += edge.GetSharpness();
++m_count;
}
}
private:
HbrHalfedge<T> const * m_edge;
float & m_childsharp;
int & m_count;
};
ChaikinEdgeCreaseOperator op(edge, childsharp, n);
vertex->GuaranteeNeighbors();
vertex->ApplyOperatorSurroundingEdges(op);
if (n) {
childsharp = childsharp * 0.25f / float(n);
}
// Add 3/4 of the sharpness of this crease edge
childsharp += sharpness * 0.75f;
childsharp -= 1.0f;
if (childsharp < (float) HbrHalfedge<T>::k_Smooth) {
childsharp = (float) HbrHalfedge<T>::k_Smooth;
}
subedge->SetSharpness(childsharp);
} else {
sharpness -= 1.0f;
if (sharpness < (float) HbrHalfedge<T>::k_Smooth) {
sharpness = (float) HbrHalfedge<T>::k_Smooth;
}
subedge->SetSharpness(sharpness);
}
}
template <class T>
void
HbrSubdivision<T>::AddSurroundingVerticesWithWeight(HbrMesh<T>* mesh, HbrVertex<T>* vertex, float weight, T* data) {
SmoothSubdivisionVertexOperator op(data, mesh->HasVertexEdits(), weight);
vertex->ApplyOperatorSurroundingVertices(op);
}
template <class T>
void
HbrSubdivision<T>::AddCreaseEdgesWithWeight(HbrMesh<T>* mesh, HbrVertex<T>* vertex, bool next, float weight, T* data) {
CreaseSubdivisionHalfedgeOperator op(vertex, data, mesh->HasVertexEdits(), next, weight);
vertex->ApplyOperatorSurroundingEdges(op);
}
} // end namespace OPENSUBDIV_VERSION
using namespace OPENSUBDIV_VERSION;
} // end namespace OpenSubdiv
#endif /* OPENSUBDIV3_HBRSUBDIVISION_H */