// Returns true if fragments have been inserted into the given ret_fragments list
bool Brush_subtract(const BrushNodePtr& brush, const Brush& other, BrushPtrVector& ret_fragments)
{
if (brush->getBrush().localAABB().intersects(other.localAABB()))
{
BrushPtrVector fragments;
fragments.reserve(other.getNumFaces());
BrushNodePtr back = std::dynamic_pointer_cast<BrushNode>(brush->clone());
for (Brush::const_iterator i(other.begin()); i != other.end(); ++i)
{
const Face& face = *(*i);
if (!face.contributes()) continue;
BrushSplitType split = Brush_classifyPlane(back->getBrush(), face.plane3());
if (split.counts[ePlaneFront] != 0 && split.counts[ePlaneBack] != 0)
{
fragments.push_back(std::dynamic_pointer_cast<BrushNode>(back->clone()));
FacePtr newFace = fragments.back()->getBrush().addFace(face);
if (newFace != 0)
{
newFace->flipWinding();
}
back->getBrush().addFace(face);
}
else if (split.counts[ePlaneBack] == 0)
{
return false;
}
}
ret_fragments.insert(ret_fragments.end(), fragments.begin(), fragments.end());
return true;
}
return false;
}
void BrushByPlaneClipper::visit(const scene::INodePtr& node) const {
// Don't clip invisible nodes
if (!node->visible()) {
return;
}
// Try to cast the instance onto a brush
Brush* brush = Node_getBrush(node);
// Return if not brush
if (brush == NULL) {
return;
}
Plane3 plane(_p0, _p1, _p2);
if (!plane.isValid()) {
return;
}
// greebo: Analyse the brush to find out which shader is the most used one
getMostUsedTexturing(brush);
BrushSplitType split = Brush_classifyPlane(*brush, _split == eFront ? -plane : plane);
if (split.counts[ePlaneBack] && split.counts[ePlaneFront]) {
// the plane intersects this brush
if (_split == eFrontAndBack) {
scene::INodePtr brushNode = GlobalBrushCreator().createBrush();
assert(brushNode != NULL);
Brush* fragment = Node_getBrush(brushNode);
assert(fragment != NULL);
fragment->copy(*brush);
FacePtr newFace = fragment->addPlane(_p0, _p1, _p2, _mostUsedShader, _mostUsedProjection);
if (newFace != NULL && _split != eFront) {
newFace->flipWinding();
}
fragment->removeEmptyFaces();
ASSERT_MESSAGE(!fragment->empty(), "brush left with no faces after split");
// Mark this brush for insertion
_insertList.insert(InsertMap::value_type(brushNode, node->getParent()));
}
FacePtr newFace = brush->addPlane(_p0, _p1, _p2, _mostUsedShader, _mostUsedProjection);
if (newFace != NULL && _split == eFront) {
newFace->flipWinding();
}
brush->removeEmptyFaces();
ASSERT_MESSAGE(!brush->empty(), "brush left with no faces after split");
}
// the plane does not intersect this brush
else if (_split != eFrontAndBack && split.counts[ePlaneBack] != 0) {
// the brush is "behind" the plane
_deleteList.insert(node);
}
}
void BrushByPlaneClipper::split(const BrushPtrVector& brushes)
{
Plane3 plane(_p0, _p1, _p2);
if (!plane.isValid())
{
return;
}
for (BrushPtrVector::const_iterator i = brushes.begin(); i != brushes.end(); ++i)
{
const BrushNodePtr& node = *i;
// Don't clip invisible nodes
if (!node->visible())
{
continue;
}
Brush& brush = node->getBrush();
scene::INodePtr parent = node->getParent();
if (!parent)
{
continue;
}
// greebo: Analyse the brush to find out which shader is the most used one
getMostUsedTexturing(brush);
BrushSplitType split = Brush_classifyPlane(brush, _split == eFront ? -plane : plane);
if (split.counts[ePlaneBack] && split.counts[ePlaneFront])
{
// the plane intersects this brush
if (_split == eFrontAndBack)
{
scene::INodePtr fragmentNode = GlobalBrushCreator().createBrush();
assert(fragmentNode != NULL);
// Put the fragment in the same layer as the brush it was clipped from
// Do this before adding the fragment to the parent, since there is an
// update algorithm setting the visibility of the fragment right there.
scene::assignNodeToLayers(fragmentNode, node->getLayers());
// greebo: For copying the texture scale the new node needs to be inserted in the scene
// otherwise the shaders cannot be captured and the scale is off
// Insert the child into the designated parent
scene::addNodeToContainer(fragmentNode, parent);
// Select the child
Node_setSelected(fragmentNode, true);
Brush* fragment = Node_getBrush(fragmentNode);
assert(fragment != NULL);
fragment->copy(brush);
FacePtr newFace = fragment->addPlane(_p0, _p1, _p2, _mostUsedShader, _mostUsedProjection);
if (newFace != NULL && _split != eFront)
{
newFace->flipWinding();
}
fragment->removeEmptyFaces();
ASSERT_MESSAGE(!fragment->empty(), "brush left with no faces after split");
}
FacePtr newFace = brush.addPlane(_p0, _p1, _p2, _mostUsedShader, _mostUsedProjection);
if (newFace != NULL && _split == eFront) {
newFace->flipWinding();
}
brush.removeEmptyFaces();
ASSERT_MESSAGE(!brush.empty(), "brush left with no faces after split");
}
// the plane does not intersect this brush
else if (_split != eFrontAndBack && split.counts[ePlaneBack] != 0)
{
// the brush is "behind" the plane
// Remove the node from the scene
scene::removeNodeFromParent(node);
}
}
}