BVH::BVH(Shape** shapes, int num_shapes) {
if (num_shapes == 1) {*this = BVH(shapes[0], shapes[0]);}
else if (num_shapes == 2) {*this = BVH(shapes[0], shapes[1]);}
//find midpoint of bbox to use as qsplit pivot
bbox = shapes[0] -> boundingBox(0.0f, 0.0f);
for (int i = 1; i < num_shapes; i++) {
bbox = surround(bbox, shapes[i] -> boundingBox(0.0f, 0.0f));
}
Vector3 pivot = (bbox.max() + bbox.min()) / 2.0f;
int midpt = QSplit::qsplit(shapes, num_shapes, pivot.x(), 0);
//create new bounding volume
left = buildBranch(shapes, midpt, 1);
right = buildBranch(&shapes[midpt], num_shapes - midpt, 1);
}
void SceneData::refreshBVH()
{
BVHItems objectItems;
for ( koi::RenderablePtr object : m_renderables )
{
const Bounds3f &bounds = object->getWorldBounds();
objectItems.push_back( BVHItem( bounds ) );
}
m_bvh = BVH( objectItems );
}