From Stephan Huber, "attached you'll find a first implementation for the obj-plugin to write

obj-files. It is not feature complete but usable.

Known issues:
* not all materials are handled correctly (especially when using
osg::StateAttribute::OVERRIDE), not all properties are supported
* could not test point and lines, all of my programs which are capable
to read obj-files only import triangle-meshes.
* only simple texture-handling"
This commit is contained in:
Robert Osfield
2007-09-26 10:58:29 +00:00
parent 1e9b4f7855
commit bfbc73785a
4 changed files with 792 additions and 2 deletions

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@@ -1,7 +1,15 @@
#this file is automatically generated
SET(TARGET_SRC ReaderWriterOBJ.cpp obj.cpp )
SET(TARGET_H obj.h )
SET(TARGET_SRC
OBJWriterNodeVisitor.cpp
ReaderWriterOBJ.cpp
obj.cpp
)
SET(TARGET_H
OBJWriterNodeVisitor.h
obj.h
)
#### end var setup ###
SETUP_PLUGIN(obj)

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@@ -0,0 +1,568 @@
// -*-c++-*-
/*
* Wavefront OBJ loader for Open Scene Graph
*
* Copyright (C) 2001 Ulrich Hertlein <u.hertlein@web.de>
*
* Modified by Robert Osfield to support per Drawable coord, normal and
* texture coord arrays, bug fixes, and support for texture mapping.
*
* Writing support added 2007 by Stephan Huber, http://digitalmind.de,
* some ideas taken from the dae-plugin
*
* The Open Scene Graph (OSG) is a cross platform C++/OpenGL library for
* real-time rendering of large 3D photo-realistic models.
* The OSG homepage is http://www.openscenegraph.org/
*/
#include <osg/io_utils>
#include "OBJWriterNodeVisitor.h"
/** writes all values of an array out to a stream, applies a matrix beforehand if necessary */
class ValueVisitor : public osg::ValueVisitor {
public:
ValueVisitor(std::ostream& fout, const osg::Matrix& m = osg::Matrix::identity(), bool isNormal = false) :
osg::ValueVisitor(),
_fout(fout),
_m(m),
_isNormal(isNormal)
{
_applyMatrix = (_m != osg::Matrix::identity());
if (_isNormal) _origin = osg::Vec3(0,0,0) * _m;
}
virtual void apply (osg::Vec2 & inv)
{
_fout << inv[0] << ' ' << inv[1];
}
virtual void apply (osg::Vec3 & inv)
{
osg::Vec3 v(inv);
if (_applyMatrix) v = (_isNormal) ? (v * _m) - _origin : v * _m;
_fout << v[0] << ' ' << v[1] << ' ' << v[2];
}
virtual void apply (osg::Vec2b & inv)
{
_fout << inv[0] << ' ' << inv[1];
}
virtual void apply (osg::Vec3b & inv)
{
osg::Vec3 v(inv[0], inv[1], inv[2]);
if (_applyMatrix) v = (_isNormal) ? (v * _m) - _origin : v * _m;
_fout << v[0] << ' ' << v[1] << ' ' << v[2];
}
virtual void apply (osg::Vec2s & inv)
{
_fout << inv[0] << ' ' << inv[1];
}
virtual void apply (osg::Vec3s & inv)
{
osg::Vec3 v(inv[0], inv[1], inv[2]);
if (_applyMatrix) v = (_isNormal) ? (v * _m) - _origin : v * _m;
_fout << v[0] << ' ' << v[1] << ' ' << v[2];
}
private:
std::ostream& _fout;
osg::Matrix _m;
bool _applyMatrix, _isNormal;
osg::Vec3 _origin;
};
/** writes all primitives of a primitive-set out to a stream, decomposes quads to triangles, line-strips to lines etc */
class PrimitiveIndexWriter : public osg::PrimitiveIndexFunctor {
public:
PrimitiveIndexWriter(std::ostream& fout,osg::Geometry* geo, unsigned int normalIndex, unsigned int lastVertexIndex, unsigned int lastNormalIndex, unsigned int lastTexIndex) :
osg::PrimitiveIndexFunctor(),
_fout(fout),
_lastVertexIndex(lastVertexIndex),
_lastNormalIndex(lastNormalIndex),
_lastTexIndex(lastTexIndex),
_hasNormalCoords(geo->getNormalArray() != NULL),
_hasTexCoords(geo->getTexCoordArray(0) != NULL),
_geo(geo),
_normalIndex(normalIndex)
{
}
virtual void setVertexArray(unsigned int,const osg::Vec2*) {}
virtual void setVertexArray(unsigned int ,const osg::Vec3* ) {}
virtual void setVertexArray(unsigned int,const osg::Vec4* ) {}
void write(unsigned int i)
{
_fout << (i + _lastVertexIndex) << "/";
if (_hasTexCoords || _hasNormalCoords)
{
if (_hasTexCoords)
_fout << (i + _lastTexIndex);
_fout << "/";
if (_hasNormalCoords)
{
if (_geo->getNormalBinding() == osg::Geometry::BIND_PER_VERTEX)
_fout << (i+_lastNormalIndex);
else
_fout << (_normalIndex + _lastNormalIndex);
}
}
_fout << " ";
}
// operator for triangles
void writeTriangle(unsigned int i1, unsigned int i2, unsigned int i3)
{
_fout << "f ";
write(i1);
write(i2);
write(i3);
_fout << std::endl;
// not sure if this is correct?
if(_geo->getNormalBinding() && _geo->getNormalBinding() == osg::Geometry::BIND_PER_PRIMITIVE) ++_normalIndex;
}
// operator for lines
void writeLine(unsigned int i1, unsigned int i2)
{
_fout << "l ";
write(i1);
write(i2);
_fout << std::endl;
// not sure if this is correct?
if(_geo->getNormalBinding() && _geo->getNormalBinding() == osg::Geometry::BIND_PER_PRIMITIVE) ++_normalIndex;
}
// operator for points
void writePoint(unsigned int i1)
{
_fout << "p ";
write(i1);
_fout << std::endl;
// not sure if this is correct?
if(_geo->getNormalBinding() && _geo->getNormalBinding() == osg::Geometry::BIND_PER_PRIMITIVE) ++_normalIndex;
}
virtual void begin(GLenum mode)
{
_modeCache = mode;
_indexCache.clear();
}
virtual void vertex(unsigned int vert)
{
_indexCache.push_back(vert);
}
virtual void end()
{
if (!_indexCache.empty())
{
drawElements(_modeCache,_indexCache.size(),&_indexCache.front());
}
}
virtual void drawArrays(GLenum mode,GLint first,GLsizei count);
virtual void drawElements(GLenum mode,GLsizei count,const GLubyte* indices)
{
drawElementsImplementation<GLubyte>(mode, count, indices);
}
virtual void drawElements(GLenum mode,GLsizei count,const GLushort* indices)
{
drawElementsImplementation<GLushort>(mode, count, indices);
}
virtual void drawElements(GLenum mode,GLsizei count,const GLuint* indices)
{
drawElementsImplementation<GLuint>(mode, count, indices);
}
protected:
template<typename T>void drawElementsImplementation(GLenum mode, GLsizei count, const T* indices)
{
if (indices==0 || count==0) return;
typedef const T* IndexPointer;
switch(mode)
{
case(GL_TRIANGLES):
{
IndexPointer ilast = &indices[count];
for(IndexPointer iptr=indices;iptr<ilast;iptr+=3)
writeTriangle(*iptr,*(iptr+1),*(iptr+2));
break;
}
case(GL_TRIANGLE_STRIP):
{
IndexPointer iptr = indices;
for(GLsizei i=2;i<count;++i,++iptr)
{
if ((i%2)) writeTriangle(*(iptr),*(iptr+2),*(iptr+1));
else writeTriangle(*(iptr),*(iptr+1),*(iptr+2));
}
break;
}
case(GL_QUADS):
{
IndexPointer iptr = indices;
for(GLsizei i=3;i<count;i+=4,iptr+=4)
{
writeTriangle(*(iptr),*(iptr+1),*(iptr+2));
writeTriangle(*(iptr),*(iptr+2),*(iptr+3));
}
break;
}
case(GL_QUAD_STRIP):
{
IndexPointer iptr = indices;
for(GLsizei i=3;i<count;i+=2,iptr+=2)
{
writeTriangle(*(iptr),*(iptr+1),*(iptr+2));
writeTriangle(*(iptr+1),*(iptr+3),*(iptr+2));
}
break;
}
case(GL_POLYGON): // treat polygons as GL_TRIANGLE_FAN
case(GL_TRIANGLE_FAN):
{
IndexPointer iptr = indices;
unsigned int first = *iptr;
++iptr;
for(GLsizei i=2;i<count;++i,++iptr)
{
writeTriangle(first,*(iptr),*(iptr+1));
}
break;
}
case(GL_POINTS):
{
IndexPointer ilast = &indices[count];
for(IndexPointer iptr=indices;iptr<ilast;++iptr)
{
writePoint(*iptr);
}
break;
}
case(GL_LINES):
{
IndexPointer ilast = &indices[count];
for(IndexPointer iptr=indices;iptr<ilast;iptr+=2)
{
writeLine(*iptr, *(iptr+1));
}
break;
}
case(GL_LINE_STRIP):
{
IndexPointer ilast = &indices[count];
for(IndexPointer iptr=indices+1;iptr<ilast;iptr+=2)
{
writeLine(*(iptr-1), *iptr);
}
break;
}
case(GL_LINE_LOOP):
{
IndexPointer ilast = &indices[count];
for(IndexPointer iptr=indices+1;iptr<ilast;iptr+=2)
{
writeLine(*(iptr-1), *iptr);
}
writeLine(*ilast, *indices);
break;
}
default:
// uhm should never come to this point :)
break;
}
}
private:
std::ostream& _fout;
GLenum _modeCache;
std::vector<GLuint> _indexCache;
unsigned int _lastVertexIndex, _lastNormalIndex, _lastTexIndex;
bool _hasNormalCoords, _hasTexCoords;
osg::Geometry* _geo;
unsigned int _normalIndex;
};
void PrimitiveIndexWriter::drawArrays(GLenum mode,GLint first,GLsizei count)
{
switch(mode)
{
case(GL_TRIANGLES):
{
unsigned int pos=first;
for(GLsizei i=2;i<count;i+=3,pos+=3)
{
writeTriangle(pos,pos+1,pos+2);
}
break;
}
case(GL_TRIANGLE_STRIP):
{
unsigned int pos=first;
for(GLsizei i=2;i<count;++i,++pos)
{
if ((i%2)) writeTriangle(pos,pos+2,pos+1);
else writeTriangle(pos,pos+1,pos+2);
}
break;
}
case(GL_QUADS):
{
unsigned int pos=first;
for(GLsizei i=3;i<count;i+=4,pos+=4)
{
writeTriangle(pos,pos+1,pos+2);
writeTriangle(pos,pos+2,pos+3);
}
break;
}
case(GL_QUAD_STRIP):
{
unsigned int pos=first;
for(GLsizei i=3;i<count;i+=2,pos+=2)
{
writeTriangle(pos,pos+1,pos+2);
writeTriangle(pos+1,pos+3,pos+2);
}
break;
}
case(GL_POLYGON): // treat polygons as GL_TRIANGLE_FAN
case(GL_TRIANGLE_FAN):
{
unsigned int pos=first+1;
for(GLsizei i=2;i<count;++i,++pos)
{
writeTriangle(first,pos,pos+1);
}
break;
}
case(GL_POINTS):
{
for(GLsizei i=0;i<count;++i)
{
writePoint(i);
}
break;
}
case(GL_LINES):
{
for(GLsizei i=0;i<count;i+=2)
{
writeLine(i, i+1);
}
break;
}
case(GL_LINE_STRIP):
{
for(GLsizei i=1;i<count;++i)
{
writeLine(i-1, i);
}
break;
}
case(GL_LINE_LOOP):
{
for(GLsizei i=1;i<count;++i)
{
writeLine(i-1, i);
}
writeLine(count-1, 0);
break;
}
default:
osg::notify(osg::WARN) << "OBJWriterNodeVisitor :: can't handle mode " << mode << std::endl;
break;
}
}
OBJWriterNodeVisitor::OBJMaterial::OBJMaterial(osg::Material* mat, osg::Texture* tex) :
diffuse(1,1,1,1),
ambient(0.2,0.2,0.2,1),
specular(0,0,0,1),
image("")
{
static unsigned int s_objmaterial_id = 0;
++s_objmaterial_id;
std::stringstream ss;
ss << "material_" << s_objmaterial_id;
name = ss.str();
if (mat) {
diffuse = mat->getDiffuse(osg::Material::FRONT);
ambient = mat->getAmbient(osg::Material::FRONT);
specular = mat->getSpecular(osg::Material::FRONT);
}
if (tex) {
osg::Image* img = tex->getImage(0);
if ((img) && (!img->getFileName().empty()))
image = img->getFileName();
}
}
std::ostream& operator<<(std::ostream& fout, const OBJWriterNodeVisitor::OBJMaterial& mat) {
fout << "newmtl " << mat.name << std::endl;
fout << " " << "Ka " << mat.ambient << std::endl;
fout << " " << "Kd " << mat.diffuse << std::endl;
fout << " " << "Ks " << mat.specular << std::endl;
if(!mat.image.empty())
fout << " " << "map_Kd " << mat.image << std::endl;
return fout;
}
void OBJWriterNodeVisitor::writeMaterials(std::ostream& fout)
{
for(MaterialMap::iterator i = _materialMap.begin(); i != _materialMap.end(); ++i)
{
fout << (*i).second << std::endl;
}
}
std::string OBJWriterNodeVisitor::getUniqueName(const std::string& defaultvalue) {
std::string name = "";
for(std::list<std::string>::iterator i = _nameStack.begin(); i != _nameStack.end(); ++i) {
if (!name.empty()) name+="_";
name += (*i);
}
if (!defaultvalue.empty())
name += "_" +defaultvalue;
if (_nameMap.find(name) == _nameMap.end())
_nameMap.insert(std::make_pair(name, 0));
std::stringstream ss;
ss << name << "_" << _nameMap[name];
++(_nameMap[name]);
return ss.str();
}
void OBJWriterNodeVisitor::processArray(const std::string& key, osg::Array* array, const osg::Matrix& m, bool isNormal)
{
if (array == NULL)
return;
ValueVisitor vv(_fout, m, isNormal);
_fout << std::endl;
for(unsigned int i = 0; i < array->getNumElements(); ++i) {
_fout << key << ' ';
array->accept(i, vv);
_fout << std::endl;
}
_fout << "# " << array->getNumElements() << " elements written" << std::endl;
}
void OBJWriterNodeVisitor::processStateSet(osg::StateSet* ss)
{
if (_materialMap.find(ss) != _materialMap.end()) {
_fout << "usemtl " << _materialMap[ss].name << std::endl;
return;
}
osg::Material* mat = dynamic_cast<osg::Material*>(ss->getAttribute(osg::StateAttribute::MATERIAL));
osg::Texture* tex = dynamic_cast<osg::Texture*>(ss->getTextureAttribute(0, osg::StateAttribute::TEXTURE));
if (mat || tex)
{
_materialMap.insert(std::make_pair(ss, OBJMaterial(mat, tex)));
_fout << "usemtl " << _materialMap[ss].name << std::endl;
}
}
void OBJWriterNodeVisitor::processGeometry(osg::Geometry* geo, osg::Matrix& m) {
_fout << std::endl;
_fout << "o " << getUniqueName( geo->getName().empty() ? geo->className() : geo->getName() ) << std::endl;
processStateSet(_currentStateSet.get());
processArray("v", geo->getVertexArray(), m, false);
processArray("vn", geo->getNormalArray(), m, true);
processArray("vt", geo->getTexCoordArray(0)); // we support only tex-unit 0
unsigned int normalIndex = 0;
for(unsigned int i = 0; i < geo->getNumPrimitiveSets(); ++i)
{
osg::PrimitiveSet* ps = geo->getPrimitiveSet(i);
PrimitiveIndexWriter pif(_fout, geo, normalIndex, _lastVertexIndex, _lastNormalIndex, _lastTexIndex);
ps->accept(pif);
if(geo->getNormalArray() && geo->getNormalBinding() == osg::Geometry::BIND_PER_PRIMITIVE_SET)
++normalIndex;
}
if (geo->getVertexArray())
_lastVertexIndex += geo->getVertexArray()->getNumElements();
if (geo->getNormalArray())
_lastNormalIndex += geo->getNormalArray()->getNumElements();
if(geo->getTexCoordArray(0))
_lastTexIndex += geo->getTexCoordArray(0)->getNumElements();
}
void OBJWriterNodeVisitor::apply( osg::Geode &node )
{
pushStateSet(node.getStateSet());
_nameStack.push_back(node.getName());
osg::Matrix m = osg::computeLocalToWorld(getNodePath());
unsigned int count = node.getNumDrawables();
for ( unsigned int i = 0; i < count; i++ )
{
osg::Geometry *g = node.getDrawable( i )->asGeometry();
if ( g != NULL )
{
pushStateSet(g->getStateSet());
processGeometry(g,m);
popStateSet(g->getStateSet());
}
}
popStateSet(node.getStateSet());
_nameStack.pop_back();
}

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@@ -0,0 +1,160 @@
// -*-c++-*-
/*
* Wavefront OBJ loader for Open Scene Graph
*
* Copyright (C) 2001 Ulrich Hertlein <u.hertlein@web.de>
*
* Modified by Robert Osfield to support per Drawable coord, normal and
* texture coord arrays, bug fixes, and support for texture mapping.
*
* Writing support added 2007 by Stephan Huber, http://digitalmind.de,
* some ideas taken from the dae-plugin
*
* The Open Scene Graph (OSG) is a cross platform C++/OpenGL library for
* real-time rendering of large 3D photo-realistic models.
* The OSG homepage is http://www.openscenegraph.org/
*/
#ifndef OBJ_WRITER_NODE_VISITOR_HEADER__
#define OBJ_WRITER_NODE_VISITOR_HEADER__
#include <string>
#include <stack>
#include <sstream>
#include <osg/Notify>
#include <osg/Node>
#include <osg/MatrixTransform>
#include <osg/Geode>
#include <osg/Geometry>
#include <osg/StateSet>
#include <osg/Material>
#include <osg/Texture2D>
#include <osg/TexGen>
#include <osg/TexMat>
#include <osgDB/Registry>
#include <osgDB/ReadFile>
#include <osgDB/FileUtils>
#include <osgDB/FileNameUtils>
#include <map>
#include <set>
class OBJWriterNodeVisitor: public osg::NodeVisitor {
public:
OBJWriterNodeVisitor(std::ostream& fout, const std::string materialFileName = "") :
osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ALL_CHILDREN),
_fout(fout),
_currentStateSet(new osg::StateSet()),
_lastVertexIndex(1),
_lastNormalIndex(1),
_lastTexIndex(1)
{
_fout << "# file written by OpenSceneGraph" << std::endl << std::endl;
if (!materialFileName.empty()) {
_fout << "mtllib " << materialFileName << std::endl << std::endl;
}
}
virtual void apply(osg::Geode &node);
virtual void apply(osg::Group &node)
{
_nameStack.push_back( node.getName().empty() ? node.className() : node.getName() );
_fout << std::endl;
_fout << "g " << getUniqueName() << std::endl;
osg::NodeVisitor::traverse( node );
_nameStack.pop_back();
}
void traverse (osg::Node &node)
{
pushStateSet(node.getStateSet());
osg::NodeVisitor::traverse( node );
popStateSet(node.getStateSet());
}
void pushStateSet(osg::StateSet* ss)
{
if (NULL!=ss) {
// Save our current stateset
_stateSetStack.push(_currentStateSet.get());
// merge with node stateset
_currentStateSet = static_cast<osg::StateSet*>(_currentStateSet->clone(osg::CopyOp::SHALLOW_COPY));
_currentStateSet->merge(*ss);
}
}
void popStateSet(osg::StateSet* ss)
{
if (NULL!=ss) {
// restore the previous stateset
_currentStateSet = _stateSetStack.top();
_stateSetStack.pop();
}
}
void writeMaterials(std::ostream& fout);
class OBJMaterial {
public:
OBJMaterial() {}
OBJMaterial(osg::Material* mat, osg::Texture* tex);
osg::Vec4 diffuse, ambient, specular;
std::string image;
std::string name;
};
protected:
struct CompareStateSet
{
bool operator()(const osg::ref_ptr<osg::StateSet>& ss1, const osg::ref_ptr<osg::StateSet>& ss2) const
{
//std::cout << "CompareStateSet: " << ss1->compare(*ss2, false) << " " << ss1 << " " << ss2 << std::endl;
return ss1->compare(*ss2, true) < 0;
}
};
private:
void processGeometry(osg::Geometry* geo, osg::Matrix& m);
void processArray(const std::string& key, osg::Array* array, const osg::Matrix& m = osg::Matrix::identity(), bool isNormal = false);
void processStateSet(osg::StateSet* stateset);
std::string getUniqueName(const std::string& defaultValue = "");
typedef std::stack<osg::ref_ptr<osg::StateSet> > StateSetStack;
typedef std::map< osg::ref_ptr<osg::StateSet>, OBJMaterial, CompareStateSet> MaterialMap;
std::ostream& _fout;
std::list<std::string> _nameStack;
StateSetStack _stateSetStack;
osg::ref_ptr<osg::StateSet> _currentStateSet;
std::map<std::string, unsigned int> _nameMap;
unsigned int _lastVertexIndex, _lastNormalIndex, _lastTexIndex;
MaterialMap _materialMap;
};
#endif

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@@ -8,6 +8,9 @@
* Modified by Robert Osfield to support per Drawable coord, normal and
* texture coord arrays, bug fixes, and support for texture mapping.
*
* Writing support added 2007 by Stephan Huber, http://digitalmind.de,
* some ideas taken from the dae-plugin
*
* The Open Scene Graph (OSG) is a cross platform C++/OpenGL library for
* real-time rendering of large 3D photo-realistic models.
* The OSG homepage is http://www.openscenegraph.org/
@@ -41,6 +44,7 @@
#include <osgUtil/Tessellator>
#include "obj.h"
#include "OBJWriterNodeVisitor.h"
#include <map>
#include <set>
@@ -58,6 +62,56 @@ public:
virtual ReadResult readNode(const std::string& fileName, const osgDB::ReaderWriter::Options* options) const;
virtual ReadResult readNode(std::istream& fin, const Options* options) const;
virtual WriteResult writeObject(const osg::Object& obj,const std::string& fileName,const Options* options=NULL) const
{
const osg::Node* node = dynamic_cast<const osg::Node*>(&obj);
if (node)
return writeNode(*node, fileName, options);
else
return WriteResult(WriteResult::FILE_NOT_HANDLED);
}
virtual WriteResult writeNode(const osg::Node& node,const std::string& fileName,const Options* options =NULL) const
{
if (!acceptsExtension(osgDB::getFileExtension(fileName)))
return WriteResult(WriteResult::FILE_NOT_HANDLED);
std::ofstream f(fileName.c_str());
std::string materialFile = osgDB::getNameLessExtension(fileName) + ".mtl";
OBJWriterNodeVisitor nv(f, osgDB::getSimpleFileName(materialFile));
// we must cast away constness
(const_cast<osg::Node*>(&node))->accept(nv);
std::ofstream mf(materialFile.c_str());
nv.writeMaterials(mf);
return WriteResult(WriteResult::FILE_SAVED);
}
virtual WriteResult writeObject(const osg::Object& obj,std::ostream& fout,const Options* options=NULL) const
{
const osg::Node* node = dynamic_cast<const osg::Node*>(&obj);
if (node)
return writeNode(*node, fout, options);
else
return WriteResult(WriteResult::FILE_NOT_HANDLED);
}
virtual WriteResult writeNode(const osg::Node& node,std::ostream& fout,const Options* =NULL) const
{
// writing to a stream does not support materials
OBJWriterNodeVisitor nv(fout);
// we must cast away constness
(const_cast<osg::Node*>(&node))->accept(nv);
return WriteResult(WriteResult::FILE_SAVED);
}
protected: