godot/thirdparty/thekla_atlas/nvmesh/halfedge/Edge.h

71 lines
1.8 KiB
C++

// This code is in the public domain -- castanyo@yahoo.es
#pragma once
#ifndef NV_MESH_HALFEDGE_EDGE_H
#define NV_MESH_HALFEDGE_EDGE_H
#include "nvmath/Vector.h"
namespace nv
{
namespace HalfEdge { class Vertex; class Face; class Edge; }
/// Half edge edge.
class HalfEdge::Edge
{
NV_FORBID_COPY(Edge);
public:
uint id;
Edge * next;
Edge * prev; // This is not strictly half-edge, but makes algorithms easier and faster.
Edge * pair;
Vertex * vertex;
Face * face;
// Default constructor.
Edge(uint id) : id(id), next(NULL), prev(NULL), pair(NULL), vertex(NULL), face(NULL)
{
}
// Vertex queries.
const Vertex * from() const { return vertex; }
Vertex * from() { return vertex; }
const Vertex * to() const { return pair->vertex; } // This used to be 'next->vertex', but that changed often when the connectivity of the mesh changes.
Vertex * to() { return pair->vertex; }
// Edge queries.
void setNext(Edge * e) { next = e; if (e != NULL) e->prev = this; }
void setPrev(Edge * e) { prev = e; if (e != NULL) e->next = this; }
// @@ Add these helpers:
//Edge * nextBoundary();
//Edge * prevBoundary();
// @@ It would be more simple to only check m_pair == NULL
// Face queries.
bool isBoundary() const { return !(face && pair->face); }
// @@ This is not exactly accurate, we should compare the texture coordinates...
bool isSeam() const { return vertex != pair->next->vertex || next->vertex != pair->vertex; }
bool isValid() const;
// Geometric queries.
Vector3 midPoint() const;
float length() const;
float angle() const;
};
} // nv namespace
#endif // NV_MESH_HALFEDGE_EDGE_H