void StrokeIntersector::intersect(osgUtil::IntersectionVisitor &iv, osg::Drawable *drawable)
{
osg::BoundingBox bb = drawable->getBoundingBox();
bb.xMin() -= m_offset; bb.xMax() += m_offset;
bb.yMin() -= m_offset; bb.yMax() += m_offset;
bb.zMin() -= m_offset; bb.zMax() += m_offset;
osg::Vec3d s(_start), e(_end);
if (!intersectAndClip(s, e, bb)) return;
if (iv.getDoDummyTraversal()) return;
entity::Stroke* geometry = dynamic_cast<entity::Stroke*>(drawable->asGeometry());
if (geometry)
{
osg::Vec3Array* vertices = dynamic_cast<osg::Vec3Array*>(geometry->getVertexArray());
if (!vertices) return;
for (unsigned int i=1; i<vertices->size(); ++i)
{
double distance = Utilities::getSkewLinesDistance(s,e,(*vertices)[i], (*vertices)[i-1]);
if (m_offset<distance) continue;
Intersection hit;
hit.ratio = distance;
hit.nodePath = iv.getNodePath();
hit.drawable = drawable;
hit.matrix = iv.getModelMatrix();
hit.localIntersectionPoint = (*vertices)[i];
m_hitIndices.push_back(i);
insertIntersection(hit);
}
}
}
static void findIntersections(UPolygon* subject, UPolygon* clipping)
{
PointNode* A = subject->pointList;
while (A != NULL) {
PointNode* B = A->next[subject->name];
PointNode* tmp = B;
if (B == NULL) B = subject->pointList;
PointNode* C = clipping->pointList;
while (C != NULL) {
PointNode* D = C->next[clipping->name];
while (D != NULL && D->isIntersection(clipping->name))
//skip past intersections
D = D->next[clipping->name];
if (D != NULL) insertIntersection(subject, clipping,A,B,C,D);
else insertIntersection(subject,clipping,A,B,C,clipping->pointList); // loopback on clipping
C = D;
}
A = tmp;
}
}
