agg::trans_affine transform(box2d<double> & bbox) const
{
bbox *= image_tr_;
coord<double, 2> c = bbox.center();
agg::trans_affine mtx = agg::trans_affine_translation(
0.5 * bbox.width() - c.x,
0.5 * bbox.height() - c.y);
return image_tr_ * mtx;
}
void split_box(box2d<double> const& node_extent,box2d<double> * ext)
{
coord2d c=node_extent.center();
double width=node_extent.width();
double height=node_extent.height();
double lox=node_extent.minx();
double loy=node_extent.miny();
double hix=node_extent.maxx();
double hiy=node_extent.maxy();
ext[0]=box2d<double>(lox,loy,lox + width * ratio_,loy + height * ratio_);
ext[1]=box2d<double>(hix - width * ratio_,loy,hix,loy + height * ratio_);
ext[2]=box2d<double>(lox,hiy - height*ratio_,lox + width * ratio_,hiy);
ext[3]=box2d<double>(hix - width * ratio_,hiy - height*ratio_,hix,hiy);
}