OpenSceneGraph/include/osgUtil/Tesselator
2004-08-27 08:01:17 +00:00

233 lines
7.9 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* OpenSceneGraph Public License for more details.
*/
#ifndef OSGUTIL_Tesselator
#define OSGUTIL_Tesselator
#include <osg/Geometry>
#include <osgUtil/Export>
#include <osg/GLU>
#include <vector>
/* Win32 calling conventions. (or a least thats what the GLUT example tess.c uses.)*/
#ifndef CALLBACK
#define CALLBACK
#endif
namespace osgUtil {
/** Originally a simple class for tessellating a single polygon boundary.
* Using old style glu tessellation functions for portability.
* Upgraded Jan 2004 to use the modern glu tessellation functions.*/
class OSGUTIL_EXPORT Tesselator : public osg::Referenced
{
public:
Tesselator();
~Tesselator();
/** The winding rule, see red book ch 11. */
enum WindingType{
TESS_WINDING_ODD = GLU_TESS_WINDING_ODD,
TESS_WINDING_NONZERO = GLU_TESS_WINDING_NONZERO ,
TESS_WINDING_POSITIVE = GLU_TESS_WINDING_POSITIVE ,
TESS_WINDING_NEGATIVE = GLU_TESS_WINDING_NEGATIVE ,
TESS_WINDING_ABS_GEQ_TWO = GLU_TESS_WINDING_ABS_GEQ_TWO
} ;
/** we interpret all contours in the geometry as a single set to be tesselated or
* each separate drawable's contours needs to be tesselated. */
enum TesselationType {
TESS_TYPE_GEOMETRY, // tesselate everything in the geometry object
TESS_TYPE_DRAWABLE, // tesselate each polygon, triangles & quads drawables in geometry separately
TESS_TYPE_POLYGONS // tesselate ONLY polygon drawables in geometry separately
};
/** Set and get tesselation request boundary only on/off */
void setBoundaryOnly (const bool tt) { _boundaryOnly=tt;}
inline const bool getBoundaryOnly ( ) { return _boundaryOnly;}
/** Set and get tesselation windong rule */
void setWindingType (const WindingType wt) { _wtype=wt;}
inline const WindingType getWindingType ( ) { return _wtype;}
/** Set and get tesselation type */
void setTesselationType (const TesselationType tt) { _ttype=tt;}
inline const TesselationType getTesselationType ( ) { return _ttype;}
/** Change the contours lists of the geometry into tesselated primitives (the
* list of primitives in the original geometry is stored in the tesselator for
* possible re-use.
* The name remains retesselatePolygons although it now handles trifans, strips, quads etc.
* as well as Polygons so as to not break old codes relying on this function name. */
void retesselatePolygons(osg::Geometry &cxgeom);
osg::Geometry::PrimitiveSetList getContours() { return _Contours;}
typedef std::vector<osg::Vec3*> VertexPointList;
struct Prim : public osg::Referenced
{
Prim(GLenum mode):_mode(mode) {}
typedef std::vector<osg::Vec3*> VecList;
GLenum _mode;
VecList _vertices;
};
void beginTesselation();
void beginContour();
void addVertex(osg::Vec3* vertex);
void endContour();
void endTesselation();
typedef std::vector< osg::ref_ptr<Prim> > PrimList;
PrimList& getPrimList() { return _primList; }
void reset();
protected:
/** remove unused parts of the array, eg for wehn retesselating
* tesselation can introduce extra vertices for concave or crossing boundaries,
* these will leak memory if not removed when retesselating. */
void reduceArray(osg::Array * cold, const unsigned int nnu);
void collectTesselation(osg::Geometry &cxgeom);
typedef std::map<osg::Vec3*,unsigned int> VertexPtrToIndexMap;
void addContour(GLenum mode, unsigned int first, unsigned int last, osg::Vec3Array* vertices);
void addContour(osg::PrimitiveSet* primitive, osg::Vec3Array* vertices);
void handleNewVertices(osg::Geometry& geom,VertexPtrToIndexMap &vertexPtrToIndexMap);
void begin(GLenum mode);
void vertex(osg::Vec3* vertex);
void combine(osg::Vec3* vertex,void* vertex_data[4],GLfloat weight[4]);
void end();
void error(GLenum errorCode);
static void CALLBACK beginCallback(GLenum which, void* userData);
static void CALLBACK vertexCallback(GLvoid *data, void* userData);
static void CALLBACK combineCallback(GLdouble coords[3], void* vertex_data[4],
GLfloat weight[4], void** outData,
void* useData);
static void CALLBACK endCallback(void* userData);
static void CALLBACK errorCallback(GLenum errorCode, void* userData);
struct Vec3d
{
double _v[3];
};
struct NewVertex
{
NewVertex():
_vpos(0),
_f1(0),
_v1(0),
_f2(0),
_v2(0),
_f3(0),
_v3(0),
_f4(0),
_v4(0) {}
NewVertex(const NewVertex& nv):
_vpos(nv._vpos),
_f1(nv._f1),
_v1(nv._v1),
_f2(nv._f2),
_v2(nv._v2),
_f3(nv._f3),
_v3(nv._v3),
_f4(nv._f4),
_v4(nv._v4) {}
NewVertex(osg::Vec3* vx,
float f1,osg::Vec3* v1,
float f2,osg::Vec3* v2,
float f3,osg::Vec3* v3,
float f4,osg::Vec3* v4):
_vpos(vx),
_f1(f1),
_v1(v1),
_f2(f2),
_v2(v2),
_f3(f3),
_v3(v3),
_f4(f4),
_v4(v4) {}
osg::Vec3 *_vpos; // added gwm Jan 2004 the vertex coords s.t. NewVertex can be used in a std::vector
float _f1;
osg::Vec3* _v1;
float _f2;
osg::Vec3* _v2;
float _f3;
osg::Vec3* _v3;
float _f4;
osg::Vec3* _v4;
};
//change NewVertexList from std::map<osg::Vec3*,NewVertex> NewVertexList;
// because this has undefined order of insertion for new vertices.
// which occasionally corrupted the texture mapping.
typedef std::vector<NewVertex> NewVertexList;
typedef std::vector<Vec3d*> Vec3dList;
GLUtesselator* _tobj;
PrimList _primList;
Vec3dList _coordData;
NewVertexList _newVertexList;
GLenum _errorCode;
/** winding rule, which parts will become solid */
WindingType _wtype;
/** tesselation rule, which parts will become solid */
TesselationType _ttype;
bool _boundaryOnly; // see gluTessProperty - if true: make the boundary edges only.
/** number of vertices that are part of the 'original' set of contours */
unsigned int _numberVerts;
/** List of primitives that define the contours */
osg::Geometry::PrimitiveSetList _Contours;
/** count number of primitives in a geometry to get right no. of norms/colurs etc for per_primitive attributes. */
unsigned int _index;
};
}
#endif