void ForestTechniqueManager::createTreeList(osg::Node* terrain,const osg::Vec3& origin, const osg::Vec3& size,unsigned int numTreesToCreate,TreeList& trees)
{
float max_TreeHeight = sqrtf(size.length2()/(float)numTreesToCreate);
float max_TreeWidth = max_TreeHeight*0.5f;
float min_TreeHeight = max_TreeHeight*0.3f;
float min_TreeWidth = min_TreeHeight*0.5f;
trees.reserve(trees.size()+numTreesToCreate);
for(unsigned int i=0;i<numTreesToCreate;++i)
{
Tree* tree = new Tree;
tree->_position.set(random(origin.x(),origin.x()+size.x()),random(origin.y(),origin.y()+size.y()),origin.z());
tree->_color.set(random(128,255),random(128,255),random(128,255),255);
tree->_width = random(min_TreeWidth,max_TreeWidth);
tree->_height = random(min_TreeHeight,max_TreeHeight);
tree->_type = 0;
if (terrain)
{
osg::ref_ptr<osgUtil::LineSegmentIntersector> intersector =
new osgUtil::LineSegmentIntersector(tree->_position,tree->_position+osg::Vec3(0.0f,0.0f,size.z()));
osgUtil::IntersectionVisitor iv(intersector.get());
terrain->accept(iv);
if (intersector->containsIntersections())
{
osgUtil::LineSegmentIntersector::Intersections& intersections = intersector->getIntersections();
for(osgUtil::LineSegmentIntersector::Intersections::iterator itr = intersections.begin();
itr != intersections.end();
++itr)
{
const osgUtil::LineSegmentIntersector::Intersection& intersection = *itr;
tree->_position = intersection.getWorldIntersectPoint();
}
}
}
trees.push_back(tree);
}
}
