Added bevel geometry

This commit is contained in:
Robert Osfield 2010-07-26 11:12:45 +00:00
parent 63ea6ae979
commit 9296391f1e

View File

@ -20,6 +20,7 @@
#include <osg/Geode>
#include <osg/Geometry>
#include <osg/PositionAttitudeTransform>
#include <osgUtil/SmoothingVisitor>
#include <osgText/Font3D>
#include <osgDB/WriteFile>
#include <osgGA/StateSetManipulator>
@ -32,7 +33,6 @@ extern int main_orig(int, char**);
extern int main_test(int, char**);
class Boundary
{
public:
@ -40,11 +40,15 @@ public:
typedef std::pair<unsigned int, unsigned int> Segment;
typedef std::vector<Segment> Segments;
osg::ref_ptr<osg::Vec3Array> _vertices;
unsigned int _start;
unsigned int _count;
Segments _segments;
Boundary(osg::Vec3Array* vertices, unsigned int start, unsigned int count)
{
_vertices = vertices;
_start = start;
_count = count;
if ((*_vertices)[start]==(*_vertices)[start+count-1])
{
@ -56,21 +60,22 @@ public:
}
_segments.reserve(count-1);
for(unsigned int i=start; i<start+count-1; ++i)
for(unsigned int i=start; i<start+count-2; ++i)
{
_segments.push_back(Segment(i,i+1));
}
_segments.push_back(Segment(start+count-2,start));
}
osg::Vec3 computeRayIntersectionPoint(const osg::Vec3& a, const osg::Vec3& an, const osg::Vec3& c, const osg::Vec3& cn)
{
float denominator = ( cn.x() * an.y() - cn.y() * an.x());
if (denominator==0.0)
if (denominator==0.0f)
{
//OSG_NOTICE<<"computeRayIntersectionPoint()<<denominator==0.0"<<std::endl;
// line segments must be parallel.
return (a+c)*0.5;
return (a+c)*0.5f;
}
float t = ((a.x()-c.x())*an.y() - (a.y()-c.y())*an.x()) / denominator;
@ -138,6 +143,7 @@ public:
return thickness;
}
float computeThickness(unsigned int i)
{
Segment& seg_before = _segments[ (i+_segments.size()-1) % _segments.size() ];
@ -205,7 +211,7 @@ public:
// OSG_NOTICE<<"bisector_abcd = "<<bisector_abcd<<", ab_sidevector="<<ab_sidevector<<", b-a="<<b-a<<", scale_factor="<<scale_factor<<std::endl;
new_vertex.z() += 0.5f;
new_vertex.z() += 5.0f;
return new_vertex;
}
@ -216,36 +222,119 @@ public:
if (geometry->getVertexArray()==0) geometry->setVertexArray(new osg::Vec3Array);
osg::Vec3Array* new_vertices = dynamic_cast<osg::Vec3Array*>(geometry->getVertexArray());
unsigned int first = new_vertices->size();
unsigned int count = 0;
// allocate the primitive set to store the face geometry
osg::DrawElementsUShort* face = new osg::DrawElementsUShort(GL_POLYGON);
face->setName("face");
// reserve enough space in the vertex array to accomodate the vertices associated with the segments
// new_vertices->reserve(new_vertices->size()+_segments.size()+1);
new_vertices->reserve(new_vertices->size() + _segments.size()+1 + _count);
// create vertices
unsigned int previous_second = _segments[0].second;
osg::Vec3 newPoint = computeBisectorPoint(0, targetThickness);
unsigned int first = new_vertices->size();
new_vertices->push_back(newPoint);
++count;
if (_segments[0].first != _start)
{
//OSG_NOTICE<<"We have pruned from the start"<<std::endl;
for(unsigned int j=_start; j<=_segments[0].first;++j)
{
face->push_back(first);
}
}
else
{
face->push_back(first);
}
for(unsigned int i=1; i<_segments.size(); ++i)
{
previous_second = _segments[i].second;
newPoint = computeBisectorPoint(i, targetThickness);
unsigned int vi = new_vertices->size();
new_vertices->push_back(newPoint);
++count;
if (previous_second != _segments[i].first)
{
//OSG_NOTICE<<"Gap in boundary"<<previous_second<<" to "<<_segments[i].first<<std::endl;
for(unsigned int j=previous_second; j<=_segments[i].first;++j)
{
face->push_back(vi);
}
}
else
{
face->push_back(vi);
}
previous_second = _segments[i].second;
}
// repeat the first point to make it a full closed loop
new_vertices->push_back((*new_vertices)[first]);
++count;
// fill the end of the polygon with repititions of the first index in the polygon to ensure
// that the orignal and new boundary polygons have the same number and pairing of indices.
// This ensures that the bevel can be created coherently.
while(face->size() < _count)
{
face->push_back(first);
}
// add DrawArrays primitive set for polygon
if (count!=0) geometry->addPrimitiveSet(new osg::DrawArrays(GL_POLYGON, first, count));
// add face primitive set for polygon
geometry->addPrimitiveSet(face);
osg::DrawElementsUShort* bevel = new osg::DrawElementsUShort(GL_QUAD_STRIP);
bevel->setName("bevel");
bevel->reserve(_count*2);
for(unsigned int i=0; i<_count; ++i)
{
unsigned int vi = new_vertices->size();
new_vertices->push_back((*_vertices)[_start+i]);
bevel->push_back(vi);
bevel->push_back((*face)[i]);
}
geometry->addPrimitiveSet(bevel);
}
};
osg::Geometry* getGeometryComponent(osg::Geometry* geometry, bool bevel)
{
osg::Vec3Array* vertices = dynamic_cast<osg::Vec3Array*>(geometry->getVertexArray());
if (!vertices) return 0;
osg::Geometry* new_geometry = new osg::Geometry;
osg::Vec3Array* new_vertices = new osg::Vec3Array(*vertices);
new_geometry->setVertexArray(new_vertices);
for(unsigned int i=0; i<geometry->getNumPrimitiveSets(); ++i)
{
osg::PrimitiveSet* primitiveSet = geometry->getPrimitiveSet(i);
if (primitiveSet->getName()=="bevel")
{
if (bevel) new_geometry->addPrimitiveSet(primitiveSet);
}
else
{
if (!bevel) new_geometry->addPrimitiveSet(primitiveSet);
}
}
osg::Vec4Array* new_colours = new osg::Vec4Array;
new_colours->push_back(bevel ? osg::Vec4(1.0,1.0,0.0,1.0) : osg::Vec4(1.0,0.0,0.0,1.0));
new_geometry->setColorArray(new_colours);
new_geometry->setColorBinding(osg::Geometry::BIND_OVERALL);
if (!bevel)
{
osg::Vec3Array* normals = new osg::Vec3Array;
normals->push_back(osg::Vec3(0.0,0.0,1.0));
new_geometry->setNormalArray(normals);
new_geometry->setNormalBinding(osg::Geometry::BIND_OVERALL);
}
return new_geometry;
}
osg::Geometry* computeThickness(osg::Geometry* orig_geometry, float thickness)
{
@ -255,11 +344,6 @@ osg::Geometry* computeThickness(osg::Geometry* orig_geometry, float thickness)
osg::Geometry* new_geometry = new osg::Geometry;
osg::Vec4Array* new_colours = new osg::Vec4Array;
new_colours->push_back(osg::Vec4(1.0,1.0,0.0,1.0));
new_geometry->setColorArray(new_colours);
new_geometry->setColorBinding(osg::Geometry::BIND_OVERALL);
for(osg::Geometry::PrimitiveSetList::iterator itr = orig_primitives.begin();
itr != orig_primitives.end();
++itr)
@ -268,8 +352,6 @@ osg::Geometry* computeThickness(osg::Geometry* orig_geometry, float thickness)
if (drawArray && drawArray->getMode()==GL_POLYGON)
{
Boundary boundary(orig_vertices, drawArray->getFirst(), drawArray->getCount());
boundary.computeAllThickness();
boundary.removeAllSegmentsBelowThickness(thickness);
boundary.addBoundaryToGeometry(new_geometry, thickness);
}
@ -343,10 +425,20 @@ int main(int argc, char** argv)
geometry->setColorArray(colours);
geometry->setColorBinding(osg::Geometry::BIND_OVERALL);
osg::Geometry* bevel = computeThickness(geometry, thickness);
osg::ref_ptr<osg::Geometry> face_and_bevel = computeThickness(geometry, thickness);
if (bevel) geode->addDrawable(bevel);
osg::Geometry* bevel = getGeometryComponent(face_and_bevel, true);
if (bevel)
{
geode->addDrawable(bevel);
osgUtil::SmoothingVisitor smoother;
smoother.smooth(*bevel);
}
osg::Geometry* face = getGeometryComponent(face_and_bevel, false);
if (face) geode->addDrawable(face);
if (useTessellator)
{
if (geometry)
@ -357,12 +449,12 @@ int main(int argc, char** argv)
ts.retessellatePolygons(*geometry);
}
if (bevel)
if (face)
{
osgUtil::Tessellator ts;
ts.setWindingType(osgUtil::Tessellator::TESS_WINDING_POSITIVE);
ts.setTessellationType(osgUtil::Tessellator::TESS_TYPE_GEOMETRY);
ts.retessellatePolygons(*bevel);
ts.retessellatePolygons(*face);
}
}
@ -374,6 +466,8 @@ int main(int argc, char** argv)
group->addChild(transform.get());
}
std::string filename;
if (arguments.read("-o", filename)) osgDB::writeNodeFile(*group, filename);
@ -381,4 +475,4 @@ int main(int argc, char** argv)
viewer.setSceneData(group.get());
viewer.addEventHandler( new osgGA::StateSetManipulator(viewer.getCamera()->getOrCreateStateSet()) );
return viewer.run();
}
}