Optimize bounding box bisection with more early culling

[libs/math.git] / source / geometry / transformedshape.h

diff --git a/source/geometry/transformedshape.h b/source/geometry/transformedshape.h
index 002f3c1a1cc859485decd5830f940137f33fda16..9387123508dcf081341c076f8c4e41970a10ead0 100644 (file)
--- a/source/geometry/transformedshape.h
+++ b/source/geometry/transformedshape.h
@@ -109,7 +109,30 @@ inline unsigned TransformedShape<T, D>::get_intersections(const Ray<T, D> &ray,
 template<typename T, unsigned D>
 inline Coverage TransformedShape<T, D>::get_coverage(const BoundingBox<T, D> &bbox) const
 {
-       return shape->get_coverage(inverse_trans.transform(bbox));
+       BoundingBox<T, D> local_bbox = inverse_trans.transform(bbox);
+       Coverage coverage = shape->get_coverage(local_bbox);
+       if(coverage==PARTIAL_COVERAGE)
+       {
+               BoundingBox<T, D> outer_bbox = transformation.transform(local_bbox);
+               LinAl::Vector<T, D> min_pt = local_bbox.get_minimum_point();
+               LinAl::Vector<T, D> max_pt = local_bbox.get_maximum_point();
+               for(unsigned i=0; i<D; ++i)
+               {
+                       T scale_ratio = (1-bbox.get_dimension(i)/outer_bbox.get_dimension(i))*local_bbox.get_dimension(i);
+                       T low_gap = bbox.get_minimum_coordinate(i)-outer_bbox.get_minimum_coordinate(i);
+                       T high_gap = outer_bbox.get_maximum_coordinate(i)-bbox.get_maximum_coordinate(i);
+                       min_pt[i] += low_gap*scale_ratio;
+                       max_pt[i] -= high_gap-scale_ratio;
+               }
+
+               local_bbox = BoundingBox<T, D>(min_pt, max_pt);
+               if(shape->get_coverage(local_bbox)>=PARTIAL_COVERAGE)
+                       return PARTIAL_COVERAGE;
+               else
+                       return UNCERTAIN_COVERAGE;
+       }
+       else
+               return coverage;
 }
 
 } // namespace Geometry