]> de.git.xonotic.org Git - xonotic/netradiant.git/blobdiff - radiant/csg.cpp
radiant/brush: use std::shared_ptr
[xonotic/netradiant.git] / radiant / csg.cpp
index 5f50e7099de07e0bf926df6954a35e81dc0e9f1e..337b394176b80d0ffa08d06a038e46131d9c6c5c 100644 (file)
@@ -1,5 +1,5 @@
 /*
-   Copyright (C) 1999-2007 id Software, Inc. and contributors.
+   Copyright (C) 1999-2006 Id Software, Inc. and contributors.
    For a list of contributors, see the accompanying CONTRIBUTORS file.
 
    This file is part of GtkRadiant.
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
-#include "stdafx.h"
-#include "winding.h"
-#include "filters.h"
+#include "csg.h"
 
-/*
-   =============
-   CSG_MakeHollow
-   =============
- */
+#include "debugging/debugging.h"
 
-void Brush_Scale( brush_t* b ){
-       for ( face_t* f = b->brush_faces ; f ; f = f->next )
-       {
-               for ( int i = 0 ; i < 3 ; i++ )
-               {
-                       VectorScale( f->planepts[i], g_qeglobals.d_gridsize, f->planepts[i] );
+#include <list>
+
+#include "map.h"
+#include "brushmanip.h"
+#include "brushnode.h"
+#include "grid.h"
+
+void Face_makeBrush( Face& face, const Brush& brush, brush_vector_t& out, float offset ){
+       if ( face.contributes() ) {
+               out.push_back( new Brush( brush ) );
+               std::shared_ptr<Face> newFace = out.back()->addFace( face );
+               if ( newFace != 0 ) {
+                       newFace->flipWinding();
+                       newFace->getPlane().offset( offset );
+                       newFace->planeChanged();
                }
        }
 }
 
-void CSG_MakeHollow( void ){
-       brush_t     *b, *front, *back, *next;
-       face_t      *f;
-       face_t split;
-       vec3_t move;
-       int i;
-
-       for ( b = selected_brushes.next ; b != &selected_brushes ; b = next )
-       {
-               next = b->next;
-
-               if ( b->owner->eclass->fixedsize || b->patchBrush || b->bFiltered ) {
-                       continue;
+void Face_makeRoom( Face &face, const Brush &brush, brush_vector_t &out, float offset ){
+       if ( face.contributes() ) {
+               face.getPlane().offset( offset );
+               out.push_back( new Brush( brush ) );
+               face.getPlane().offset( -offset );
+               std::shared_ptr<Face> newFace = out.back()->addFace( face );
+               if ( newFace != 0 ) {
+                       newFace->flipWinding();
+                       newFace->planeChanged();
                }
-
-               for ( f = b->brush_faces ; f ; f = f->next )
-               {
-                       split = *f;
-                       VectorScale( f->plane.normal, g_qeglobals.d_gridsize, move );
-                       for ( i = 0 ; i < 3 ; i++ )
-                               VectorSubtract( split.planepts[i], move, split.planepts[i] );
-
-                       Brush_SplitBrushByFace( b, &split, &front, &back );
-                       if ( back ) {
-                               Brush_Free( back );
-                       }
-                       if ( front ) {
-                               Brush_AddToList( front, &selected_brushes );
-                       }
-               }
-               Brush_Free( b );
        }
-       Sys_UpdateWindows( W_ALL );
 }
 
-/*
-   =============
-   Brush_Merge
+void Brush_makeHollow( const Brush &brush, brush_vector_t &out, float offset ){
+       Brush_forEachFace( brush, [&]( Face &face ) {
+               Face_makeBrush( face, brush, out, offset );
+       } );
+}
 
-   Returns a new brush that is created by merging brush1 and brush2.
-   May return NULL if brush1 and brush2 do not create a convex brush when merged.
-   The input brushes brush1 and brush2 stay intact.
+void Brush_makeRoom( const Brush &brush, brush_vector_t &out, float offset ){
+       Brush_forEachFace( brush, [&]( Face &face ) {
+               Face_makeRoom( face, brush, out, offset );
+       } );
+}
 
-   if onlyshape is true then the merge is allowed based on the shape only
-   otherwise the texture/shader references of faces in the same plane have to
-   be the same as well.
-   =============
- */
-brush_t *Brush_Merge( brush_t *brush1, brush_t *brush2, int onlyshape ){
-       int i, shared;
-       brush_t *newbrush;
-       face_t *face1, *face2, *newface, *f;
+class BrushHollowSelectedWalker : public scene::Graph::Walker
+{
+float m_offset;
+bool m_makeRoom;
+public:
+BrushHollowSelectedWalker( float offset, bool makeRoom )
+       : m_offset( offset ), m_makeRoom( makeRoom ){
+}
 
-       // check for bounding box overlapp
-       for ( i = 0; i < 3; i++ )
-       {
-               if ( brush1->mins[i] > brush2->maxs[i] + ON_EPSILON
-                        || brush1->maxs[i] < brush2->mins[i] - ON_EPSILON ) {
-                       // never merge if the brushes overlap
-                       return NULL;
-               }
-       }
-       //
-       shared = 0;
-       // check if the new brush would be convex... flipped planes make a brush non-convex
-       for ( face1 = brush1->brush_faces; face1; face1 = face1->next )
-       {
-               // don't check the faces of brush 1 and 2 touching each other
-               for ( face2 = brush2->brush_faces; face2; face2 = face2->next )
-               {
-                       if ( Plane_Equal( &face1->plane, &face2->plane, true ) ) {
-                               shared++;
-                               // there may only be ONE shared side
-                               if ( shared > 1 ) {
-                                       return NULL;
-                               }
-                               break;
+bool pre( const scene::Path& path, scene::Instance& instance ) const {
+       if ( path.top().get().visible() ) {
+               Brush* brush = Node_getBrush( path.top() );
+               if ( brush != 0
+                        && Instance_getSelectable( instance )->isSelected()
+                        && path.size() > 1 ) {
+                       brush_vector_t out;
+
+                       if ( m_makeRoom ) {
+                               Brush_makeRoom(* brush, out, m_offset );
                        }
-               }
-               // if this face plane is shared
-               if ( face2 ) {
-                       continue;
-               }
-               //
-               for ( face2 = brush2->brush_faces; face2; face2 = face2->next )
-               {
-                       // don't check the faces of brush 1 and 2 touching each other
-                       for ( f = brush1->brush_faces; f; f = f->next )
+                       else
                        {
-                               if ( Plane_Equal( &face2->plane, &f->plane, true ) ) {
-                                       break;
-                               }
-                       }
-                       if ( f ) {
-                               continue;
-                       }
-                       //
-                       if ( Plane_Equal( &face1->plane, &face2->plane, false ) ) {
-                               //if the texture/shader references should be the same but are not
-                               if ( !onlyshape && stricmp( face1->texdef.GetName(), face2->texdef.GetName() ) != 0 ) {
-                                       return NULL;
-                               }
-                               continue;
-                       }
-                       //
-                       if ( Winding_PlanesConcave( face1->face_winding, face2->face_winding,
-                                                                               face1->plane.normal, face2->plane.normal,
-                                                                               face1->plane.dist, face2->plane.dist ) ) {
-                               return NULL;
-                       } //end if
-               } //end for
-       } //end for
-         //
-       newbrush = Brush_Alloc();
-       //
-       for ( face1 = brush1->brush_faces; face1; face1 = face1->next )
-       {
-               // don't add the faces of brush 1 and 2 touching each other
-               for ( face2 = brush2->brush_faces; face2; face2 = face2->next )
-               {
-                       if ( Plane_Equal( &face1->plane, &face2->plane, true ) ) {
-                               break;
-                       }
-               }
-               if ( face2 ) {
-                       continue;
-               }
-               // don't add faces with the same plane twice
-               for ( f = newbrush->brush_faces; f; f = f->next )
-               {
-                       if ( Plane_Equal( &face1->plane, &f->plane, false ) ) {
-                               break;
+                               Brush_makeHollow(* brush, out, m_offset );
                        }
-                       if ( Plane_Equal( &face1->plane, &f->plane, true ) ) {
-                               break;
+
+                       for ( brush_vector_t::const_iterator i = out.begin(); i != out.end(); ++i )
+                       {
+                               ( *i )->removeEmptyFaces();
+                               NodeSmartReference node( ( new BrushNode() )->node() );
+                               Node_getBrush( node )->copy( *( *i ) );
+                               delete ( *i );
+                               Node_getTraversable( path.parent() )->insert( node );
                        }
                }
-               if ( f ) {
-                       continue;
-               }
-               //
-               newface = Face_Alloc();
-               newface->texdef = face1->texdef;
-               VectorCopy( face1->planepts[0], newface->planepts[0] );
-               VectorCopy( face1->planepts[1], newface->planepts[1] );
-               VectorCopy( face1->planepts[2], newface->planepts[2] );
-               newface->plane = face1->plane;
-               newface->next = newbrush->brush_faces;
-               newbrush->brush_faces = newface;
        }
-       //
-       for ( face2 = brush2->brush_faces; face2; face2 = face2->next )
-       {
-               // don't add the faces of brush 1 and 2 touching each other
-               for ( face1 = brush1->brush_faces; face1; face1 = face1->next )
-               {
-                       if ( Plane_Equal( &face2->plane, &face1->plane, true ) ) {
-                               break;
-                       }
-               }
-               if ( face1 ) {
-                       continue;
-               }
-               // don't add faces with the same plane twice
-               for ( f = newbrush->brush_faces; f; f = f->next )
-               {
-                       if ( Plane_Equal( &face2->plane, &f->plane, false ) ) {
-                               break;
-                       }
-                       if ( Plane_Equal( &face2->plane, &f->plane, true ) ) {
-                               break;
-                       }
+       return true;
+}
+};
+
+typedef std::list<Brush*> brushlist_t;
+
+class BrushGatherSelected : public scene::Graph::Walker
+{
+brush_vector_t& m_brushlist;
+public:
+BrushGatherSelected( brush_vector_t& brushlist )
+       : m_brushlist( brushlist ){
+}
+
+bool pre( const scene::Path& path, scene::Instance& instance ) const {
+       if ( path.top().get().visible() ) {
+               Brush* brush = Node_getBrush( path.top() );
+               if ( brush != 0
+                        && Instance_getSelectable( instance )->isSelected() ) {
+                       m_brushlist.push_back( brush );
                }
-               if ( f ) {
-                       continue;
+       }
+       return true;
+}
+};
+
+class BrushDeleteSelected : public scene::Graph::Walker
+{
+public:
+bool pre( const scene::Path& path, scene::Instance& instance ) const {
+       return true;
+}
+void post( const scene::Path& path, scene::Instance& instance ) const {
+       if ( path.top().get().visible() ) {
+               Brush* brush = Node_getBrush( path.top() );
+               if ( brush != 0
+                        && Instance_getSelectable( instance )->isSelected()
+                        && path.size() > 1 ) {
+                       Path_deleteTop( path );
                }
-               //
-               newface = Face_Alloc();
-               newface->texdef = face2->texdef;
-               VectorCopy( face2->planepts[0], newface->planepts[0] );
-               VectorCopy( face2->planepts[1], newface->planepts[1] );
-               VectorCopy( face2->planepts[2], newface->planepts[2] );
-               newface->plane = face2->plane;
-               newface->next = newbrush->brush_faces;
-               newbrush->brush_faces = newface;
        }
-       // link the new brush to an entity
-       Entity_LinkBrush( brush1->owner, newbrush );
-       // build windings for the faces
-       Brush_BuildWindings( newbrush, false );
+}
+};
 
-       return newbrush;
+void Scene_BrushMakeHollow_Selected( scene::Graph& graph, bool makeRoom ){
+       GlobalSceneGraph().traverse( BrushHollowSelectedWalker( GetGridSize(), makeRoom ) );
+       GlobalSceneGraph().traverse( BrushDeleteSelected() );
 }
 
 /*
    =============
-   Brush_MergeListPairs
-
-   Returns a list with merged brushes.
-   Tries to merge brushes pair wise.
-   The input list is destroyed.
-   Input and output should be a single linked list using .next
+   CSG_MakeHollow
    =============
  */
-brush_t *Brush_MergeListPairs( brush_t *brushlist, int onlyshape ){
-       int nummerges, merged;
-       brush_t *b1, *b2, *tail, *newbrush, *newbrushlist;
-       brush_t *lastb2;
 
-       if ( !brushlist ) {
-               return NULL;
+void CSG_MakeHollow( void ){
+       UndoableCommand undo( "brushHollow" );
+
+       Scene_BrushMakeHollow_Selected( GlobalSceneGraph(), false );
+
+       SceneChangeNotify();
+}
+
+void CSG_MakeRoom( void ){
+       UndoableCommand undo( "brushRoom" );
+
+       Scene_BrushMakeHollow_Selected( GlobalSceneGraph(), true );
+
+       SceneChangeNotify();
+}
+
+template<typename Type>
+class RemoveReference
+{
+public:
+typedef Type type;
+};
+
+template<typename Type>
+class RemoveReference<Type&>
+{
+public:
+typedef Type type;
+};
+
+template<typename Functor>
+class Dereference
+{
+const Functor& functor;
+public:
+Dereference( const Functor& functor ) : functor( functor ){
+}
+get_result_type<Functor> operator()( typename RemoveReference<get_argument<Functor, 0>>::type *firstArgument ) const {
+       return functor( *firstArgument );
+}
+};
+
+template<typename Functor>
+inline Dereference<Functor> makeDereference( const Functor& functor ){
+       return Dereference<Functor>( functor );
+}
+
+template<typename Caller>
+class BindArguments1
+{
+typedef get_argument<Caller, 1> FirstBound;
+FirstBound firstBound;
+public:
+BindArguments1( FirstBound firstBound )
+       : firstBound( firstBound ){
+}
+
+get_result_type<Caller> operator()( get_argument<Caller, 0> firstArgument ) const {
+       return Caller::call( firstArgument, firstBound );
+}
+};
+
+template<typename Caller>
+class BindArguments2
+{
+typedef get_argument<Caller, 1> FirstBound;
+typedef get_argument<Caller, 2> SecondBound;
+FirstBound firstBound;
+SecondBound secondBound;
+public:
+BindArguments2( FirstBound firstBound, SecondBound secondBound )
+       : firstBound( firstBound ), secondBound( secondBound ){
+}
+
+get_result_type<Caller> operator()( get_argument<Caller, 0> firstArgument ) const {
+       return Caller::call( firstArgument, firstBound, secondBound );
+}
+};
+
+template<typename Caller, typename FirstBound, typename SecondBound>
+BindArguments2<Caller> bindArguments( const Caller& caller, FirstBound firstBound, SecondBound secondBound ){
+       return BindArguments2<Caller>( firstBound, secondBound );
+}
+
+inline bool Face_testPlane( const Face& face, const Plane3& plane, bool flipped ){
+       return face.contributes() && !Winding_TestPlane( face.getWinding(), plane, flipped );
+}
+
+typedef Function<bool ( const Face &, const Plane3 &, bool ), Face_testPlane> FaceTestPlane;
+
+
+/// \brief Returns true if
+/// \li !flipped && brush is BACK or ON
+/// \li flipped && brush is FRONT or ON
+bool Brush_testPlane( const Brush& brush, const Plane3& plane, bool flipped ){
+       brush.evaluateBRep();
+       for ( Brush::const_iterator i( brush.begin() ); i != brush.end(); ++i )
+       {
+               if ( Face_testPlane( *( *i ), plane, flipped ) ) {
+                       return false;
+               }
        }
+       return true;
+}
 
-       nummerges = 0;
-       do
+brushsplit_t Brush_classifyPlane( const Brush& brush, const Plane3& plane ){
+       brush.evaluateBRep();
+       brushsplit_t split;
+       for ( Brush::const_iterator i( brush.begin() ); i != brush.end(); ++i )
        {
-               for ( tail = brushlist; tail; tail = tail->next )
-               {
-                       if ( !tail->next ) {
-                               break;
-                       }
+               if ( ( *i )->contributes() ) {
+                       split += Winding_ClassifyPlane( ( *i )->getWinding(), plane );
                }
-               merged = 0;
-               newbrushlist = NULL;
-               for ( b1 = brushlist; b1; b1 = brushlist )
+       }
+       return split;
+}
+
+bool Brush_subtract( const Brush& brush, const Brush& other, brush_vector_t& ret_fragments ){
+       if ( aabb_intersects_aabb( brush.localAABB(), other.localAABB() ) ) {
+               brush_vector_t fragments;
+               fragments.reserve( other.size() );
+               Brush back( brush );
+
+               for ( const std::shared_ptr<Face>& b : other )
                {
-                       lastb2 = b1;
-                       for ( b2 = b1->next; b2; b2 = b2->next )
-                       {
-                               newbrush = Brush_Merge( b1, b2, onlyshape );
-                               if ( newbrush ) {
-                                       tail->next = newbrush;
-                                       lastb2->next = b2->next;
-                                       brushlist = brushlist->next;
-                                       b1->next = b1->prev = NULL;
-                                       b2->next = b2->prev = NULL;
-                                       Brush_Free( b1 );
-                                       Brush_Free( b2 );
-                                       for ( tail = brushlist; tail; tail = tail->next )
-                                       {
-                                               if ( !tail->next ) {
-                                                       break;
-                                               }
-                                       } //end for
-                                       merged++;
-                                       nummerges++;
-                                       break;
+                       if ( b->contributes() ) {
+                               brushsplit_t split = Brush_classifyPlane( back, b->plane3() );
+                               if ( split.counts[ePlaneFront] != 0
+                                        && split.counts[ePlaneBack] != 0 ) {
+                                       fragments.push_back( new Brush( back ) );
+                                       std::shared_ptr<Face> newFace = fragments.back()->addFace( *b );
+                                       if ( newFace != nullptr ) {
+                                               newFace->flipWinding();
+                                       }
+                                       back.addFace( *b );
+                               }
+                               else if ( split.counts[ePlaneBack] == 0 ) {
+                                       for ( Brush *i : fragments ) {
+                                               delete( i );
+                                       }
+                                       fragments.clear();
+                                       return false;
                                }
-                               lastb2 = b2;
-                       }
-                       //if b1 can't be merged with any of the other brushes
-                       if ( !b2 ) {
-                               brushlist = brushlist->next;
-                               //keep b1
-                               b1->next = newbrushlist;
-                               newbrushlist = b1;
                        }
                }
-               brushlist = newbrushlist;
-       } while ( merged );
-       return newbrushlist;
+               ret_fragments.insert( ret_fragments.end(), fragments.begin(), fragments.end() );
+               return true;
+       }
+       return false;
 }
 
-/*
-   =============
-   Brush_MergeList
+class SubtractBrushesFromUnselected : public scene::Graph::Walker
+{
+const brush_vector_t& m_brushlist;
+std::size_t& m_before;
+std::size_t& m_after;
+public:
+SubtractBrushesFromUnselected( const brush_vector_t& brushlist, std::size_t& before, std::size_t& after )
+       : m_brushlist( brushlist ), m_before( before ), m_after( after ){
+}
 
-   Tries to merge all brushes in the list into one new brush.
-   The input brush list stays intact.
-   Returns NULL if no merged brush can be created.
-   To create a new brush the brushes in the list may not overlap and
-   the outer faces of the brushes together should make a new convex brush.
+bool pre( const scene::Path& path, scene::Instance& instance ) const {
+       return true;
+}
 
-   if onlyshape is true then the merge is allowed based on the shape only
-   otherwise the texture/shader references of faces in the same plane have to
-   be the same as well.
-   =============
- */
-brush_t *Brush_MergeList( brush_t *brushlist, int onlyshape ){
-       brush_t *brush1, *brush2, *brush3, *newbrush;
-       face_t *face1, *face2, *face3, *newface, *f;
+void post( const scene::Path& path, scene::Instance& instance ) const {
+       if ( path.top().get().visible() ) {
+               Brush* brush = Node_getBrush( path.top() );
+               if ( brush != 0
+                        && !Instance_getSelectable( instance )->isSelected() ) {
+                       brush_vector_t buffer[2];
+                       bool swap = false;
+                       Brush* original = new Brush( *brush );
+                       buffer[static_cast<std::size_t>( swap )].push_back( original );
 
-       if ( !brushlist ) {
-               return NULL;
-       }
-       for ( brush1 = brushlist; brush1; brush1 = brush1->next )
-       {
-               // check if the new brush would be convex... flipped planes make a brush concave
-               for ( face1 = brush1->brush_faces; face1; face1 = face1->next )
-               {
-                       // don't check face1 if it touches another brush
-                       for ( brush2 = brushlist; brush2; brush2 = brush2->next )
                        {
-                               if ( brush2 == brush1 ) {
-                                       continue;
-                               }
-                               for ( face2 = brush2->brush_faces; face2; face2 = face2->next )
+                               for ( brush_vector_t::const_iterator i( m_brushlist.begin() ); i != m_brushlist.end(); ++i )
                                {
-                                       if ( Plane_Equal( &face1->plane, &face2->plane, true ) ) {
-                                               break;
+                                       for ( brush_vector_t::iterator j( buffer[static_cast<std::size_t>( swap )].begin() ); j != buffer[static_cast<std::size_t>( swap )].end(); ++j )
+                                       {
+                                               if ( Brush_subtract( *( *j ), *( *i ), buffer[static_cast<std::size_t>( !swap )] ) ) {
+                                                       delete ( *j );
+                                               }
+                                               else
+                                               {
+                                                       buffer[static_cast<std::size_t>( !swap )].push_back( ( *j ) );
+                                               }
                                        }
-                               }
-                               if ( face2 ) {
-                                       break;
+                                       buffer[static_cast<std::size_t>( swap )].clear();
+                                       swap = !swap;
                                }
                        }
-                       // if face1 touches another brush
-                       if ( brush2 ) {
-                               continue;
+
+                       brush_vector_t& out = buffer[static_cast<std::size_t>( swap )];
+
+                       if ( out.size() == 1 && out.back() == original ) {
+                               delete original;
                        }
-                       //
-                       for ( brush2 = brush1->next; brush2; brush2 = brush2->next )
+                       else
                        {
-                               // don't check the faces of brush 2 touching another brush
-                               for ( face2 = brush2->brush_faces; face2; face2 = face2->next )
+                               ++m_before;
+                               for ( brush_vector_t::const_iterator i = out.begin(); i != out.end(); ++i )
                                {
-                                       for ( brush3 = brushlist; brush3; brush3 = brush3->next )
-                                       {
-                                               if ( brush3 == brush2 ) {
-                                                       continue;
-                                               }
-                                               for ( face3 = brush3->brush_faces; face3; face3 = face3->next )
-                                               {
-                                                       if ( Plane_Equal( &face2->plane, &face3->plane, true ) ) {
-                                                               break;
-                                                       }
-                                               }
-                                               if ( face3 ) {
-                                                       break;
-                                               }
+                                       ++m_after;
+                                       ( *i )->removeEmptyFaces();
+                                       if ( !( *i )->empty() ) {
+                                               NodeSmartReference node( ( new BrushNode() )->node() );
+                                               Node_getBrush( node )->copy( *( *i ) );
+                                               delete ( *i );
+                                               Node_getTraversable( path.parent() )->insert( node );
                                        }
-                                       // if face2 touches another brush
-                                       if ( brush3 ) {
-                                               continue;
-                                       }
-                                       //
-                                       if ( Plane_Equal( &face1->plane, &face2->plane, false ) ) {
-                                               //if the texture/shader references should be the same but are not
-                                               if ( !onlyshape && stricmp( face1->texdef.GetName(), face2->texdef.GetName() ) != 0 ) {
-                                                       return NULL;
-                                               }
-                                               continue;
-                                       }
-                                       //
-                                       if ( Winding_PlanesConcave( face1->face_winding, face2->face_winding,
-                                                                                               face1->plane.normal, face2->plane.normal,
-                                                                                               face1->plane.dist, face2->plane.dist ) ) {
-                                               return NULL;
+                                       else{
+                                               delete ( *i );
                                        }
                                }
+                               Path_deleteTop( path );
                        }
                }
        }
-       //
-       newbrush = Brush_Alloc();
-       //
-       for ( brush1 = brushlist; brush1; brush1 = brush1->next )
+}
+};
+
+void CSG_Subtract(){
+       brush_vector_t selected_brushes;
+       GlobalSceneGraph().traverse( BrushGatherSelected( selected_brushes ) );
+
+       if ( selected_brushes.empty() ) {
+               globalOutputStream() << "CSG Subtract: No brushes selected.\n";
+       }
+       else
        {
-               for ( face1 = brush1->brush_faces; face1; face1 = face1->next )
-               {
-                       // don't add face1 to the new brush if it touches another brush
-                       for ( brush2 = brushlist; brush2; brush2 = brush2->next )
-                       {
-                               if ( brush2 == brush1 ) {
-                                       continue;
-                               }
-                               for ( face2 = brush2->brush_faces; face2; face2 = face2->next )
-                               {
-                                       if ( Plane_Equal( &face1->plane, &face2->plane, true ) ) {
-                                               break;
+               globalOutputStream() << "CSG Subtract: Subtracting " << Unsigned( selected_brushes.size() ) << " brushes.\n";
+
+               UndoableCommand undo( "brushSubtract" );
+
+               // subtract selected from unselected
+               std::size_t before = 0;
+               std::size_t after = 0;
+               GlobalSceneGraph().traverse( SubtractBrushesFromUnselected( selected_brushes, before, after ) );
+               globalOutputStream() << "CSG Subtract: Result: "
+                                                        << Unsigned( after ) << " fragment" << ( after == 1 ? "" : "s" )
+                                                        << " from " << Unsigned( before ) << " brush" << ( before == 1 ? "" : "es" ) << ".\n";
+
+               SceneChangeNotify();
+       }
+}
+
+class BrushSplitByPlaneSelected : public scene::Graph::Walker
+{
+const Vector3& m_p0;
+const Vector3& m_p1;
+const Vector3& m_p2;
+const char* m_shader;
+const TextureProjection& m_projection;
+EBrushSplit m_split;
+public:
+BrushSplitByPlaneSelected( const Vector3& p0, const Vector3& p1, const Vector3& p2, const char* shader, const TextureProjection& projection, EBrushSplit split )
+       : m_p0( p0 ), m_p1( p1 ), m_p2( p2 ), m_shader( shader ), m_projection( projection ), m_split( split ){
+}
+
+bool pre( const scene::Path& path, scene::Instance& instance ) const {
+       return true;
+}
+
+void post( const scene::Path& path, scene::Instance& instance ) const {
+       if ( path.top().get().visible() ) {
+               Brush* brush = Node_getBrush( path.top() );
+               if ( brush != 0
+                        && Instance_getSelectable( instance )->isSelected() ) {
+                       Plane3 plane( plane3_for_points( m_p0, m_p1, m_p2 ) );
+                       if ( plane3_valid( plane ) ) {
+                               brushsplit_t split = Brush_classifyPlane( *brush, m_split == eFront ? plane3_flipped( plane ) : plane );
+                               if ( split.counts[ePlaneBack] && split.counts[ePlaneFront] ) {
+                                       // the plane intersects this brush
+                                       if ( m_split == eFrontAndBack ) {
+                                               NodeSmartReference node( ( new BrushNode() )->node() );
+                                               Brush* fragment = Node_getBrush( node );
+                                               fragment->copy( *brush );
+                                               std::shared_ptr<Face> newFace =
+                                                       fragment->addPlane( m_p0, m_p1, m_p2, m_shader, m_projection );
+                                               if ( newFace != 0 && m_split != eFront ) {
+                                                       newFace->flipWinding();
+                                               }
+                                               fragment->removeEmptyFaces();
+                                               ASSERT_MESSAGE( !fragment->empty(), "brush left with no faces after split" );
+
+                                               Node_getTraversable( path.parent() )->insert( node );
+                                               {
+                                                       scene::Path fragmentPath = path;
+                                                       fragmentPath.top() = makeReference( node.get() );
+                                                       selectPath( fragmentPath, true );
+                                               }
                                        }
+
+                                       std::shared_ptr<Face> newFace = brush->addPlane( m_p0, m_p1, m_p2, m_shader, m_projection );
+                                       if ( newFace != 0 && m_split == eFront ) {
+                                               newFace->flipWinding();
+                                       }
+                                       brush->removeEmptyFaces();
+                                       ASSERT_MESSAGE( !brush->empty(), "brush left with no faces after split" );
                                }
-                               if ( face2 ) {
-                                       break;
-                               }
-                       }
-                       if ( brush2 ) {
-                               continue;
-                       }
-                       // don't add faces with the same plane twice
-                       for ( f = newbrush->brush_faces; f; f = f->next )
-                       {
-                               if ( Plane_Equal( &face1->plane, &f->plane, false ) ) {
-                                       break;
-                               }
-                               if ( Plane_Equal( &face1->plane, &f->plane, true ) ) {
-                                       break;
+                               else
+                               // the plane does not intersect this brush
+                               if ( m_split != eFrontAndBack && split.counts[ePlaneBack] != 0 ) {
+                                       // the brush is "behind" the plane
+                                       Path_deleteTop( path );
                                }
                        }
-                       if ( f ) {
-                               continue;
-                       }
-                       //
-                       newface = Face_Alloc();
-                       newface->texdef = face1->texdef;
-                       VectorCopy( face1->planepts[0], newface->planepts[0] );
-                       VectorCopy( face1->planepts[1], newface->planepts[1] );
-                       VectorCopy( face1->planepts[2], newface->planepts[2] );
-                       newface->plane = face1->plane;
-                       newface->next = newbrush->brush_faces;
-                       newbrush->brush_faces = newface;
                }
        }
-       // link the new brush to an entity
-       Entity_LinkBrush( brushlist->owner, newbrush );
-       // build windings for the faces
-       Brush_BuildWindings( newbrush, false );
+}
+};
 
-       return newbrush;
+void Scene_BrushSplitByPlane( scene::Graph& graph, const Vector3& p0, const Vector3& p1, const Vector3& p2, const char* shader, EBrushSplit split ){
+       TextureProjection projection;
+       TexDef_Construct_Default( projection );
+       graph.traverse( BrushSplitByPlaneSelected( p0, p1, p2, shader, projection, split ) );
+       SceneChangeNotify();
 }
 
-/*
-   =============
-   Brush_Subtract
 
-   Returns a list of brushes that remain after B is subtracted from A.
-   May by empty if A is contained inside B.
-   The originals are undisturbed.
-   =============
- */
-brush_t *Brush_Subtract( brush_t *a, brush_t *b ){
-       // a - b = out (list)
-       brush_t *front, *back;
-       brush_t *in, *out, *next;
-       face_t *f;
-
-       in = a;
-       out = NULL;
-       for ( f = b->brush_faces; f && in; f = f->next )
-       {
-               Brush_SplitBrushByFace( in, f, &front, &back );
-               if ( in != a ) {
-                       Brush_Free( in );
-               }
-               if ( front ) { // add to list
-                       front->next = out;
-                       out = front;
-               }
-               in = back;
-       }
-       //NOTE: in != a just in case brush b has no faces
-       if ( in && in != a ) {
-               Brush_Free( in );
-       }
-       else
-       {   //didn't really intersect
-               for ( b = out; b; b = next )
-               {
-                       next = b->next;
-                       b->next = b->prev = NULL;
-                       Brush_Free( b );
-               }
-               return a;
+class BrushInstanceSetClipPlane : public scene::Graph::Walker
+{
+Plane3 m_plane;
+public:
+BrushInstanceSetClipPlane( const Plane3& plane )
+       : m_plane( plane ){
+}
+
+bool pre( const scene::Path& path, scene::Instance& instance ) const {
+       BrushInstance* brush = Instance_getBrush( instance );
+       if ( brush != 0
+                && path.top().get().visible()
+                && brush->isSelected() ) {
+               BrushInstance& brushInstance = *brush;
+               brushInstance.setClipPlane( m_plane );
        }
-       return out;
+       return true;
+}
+};
+
+void Scene_BrushSetClipPlane( scene::Graph& graph, const Plane3& plane ){
+       graph.traverse( BrushInstanceSetClipPlane( plane ) );
 }
 
 /*
    =============
-   CSG_Subtract
+   CSG_Merge
    =============
  */
-void CSG_Subtract( void ){
-       brush_t     *b, *s, *fragments, *nextfragment, *frag, *next, *snext;
-       brush_t fragmentlist;
-       int i, numfragments, numbrushes;
-
-       Sys_Printf( "Subtracting...\n" );
+bool Brush_merge( Brush& brush, const brush_vector_t& in, bool onlyshape ){
+       // gather potential outer faces
 
-       if ( selected_brushes.next == &selected_brushes ) {
-               Sys_Printf( "No brushes selected.\n" );
-               return;
-       }
-
-       fragmentlist.next = &fragmentlist;
-       fragmentlist.prev = &fragmentlist;
-
-       numfragments = 0;
-       numbrushes = 0;
-       for ( b = selected_brushes.next ; b != &selected_brushes ; b = next )
        {
-               next = b->next;
+               typedef std::vector<const Face*> Faces;
+               Faces faces;
+               for ( brush_vector_t::const_iterator i( in.begin() ); i != in.end(); ++i )
+               {
+                       ( *i )->evaluateBRep();
+                       for ( Brush::const_iterator j( ( *i )->begin() ); j != ( *i )->end(); ++j )
+                       {
+                               if ( !( *j )->contributes() ) {
+                                       continue;
+                               }
 
-               if ( b->owner->eclass->fixedsize ) {
-                       continue;   // can't use texture from a fixed entity, so don't subtract
+                               const Face& face1 = *( *j );
 
-               }
-               // chop all fragments further up
-               for ( s = fragmentlist.next; s != &fragmentlist; s = snext )
-               {
-                       snext = s->next;
+                               bool skip = false;
+                               // test faces of all input brushes
+                               //!\todo SPEEDUP: Flag already-skip faces and only test brushes from i+1 upwards.
+                               for ( brush_vector_t::const_iterator k( in.begin() ); !skip && k != in.end(); ++k )
+                               {
+                                       if ( k != i ) { // don't test a brush against itself
+                                               for ( Brush::const_iterator l( ( *k )->begin() ); !skip && l != ( *k )->end(); ++l )
+                                               {
+                                                       const Face& face2 = *( *l );
 
-                       for ( i = 0 ; i < 3 ; i++ )
-                               if ( b->mins[i] >= s->maxs[i] - ON_EPSILON
-                                        || b->maxs[i] <= s->mins[i] + ON_EPSILON ) {
-                                       break;
+                                                       // face opposes another face
+                                                       if ( plane3_opposing( face1.plane3(), face2.plane3() ) ) {
+                                                               // skip opposing planes
+                                                               skip  = true;
+                                                               break;
+                                                       }
+                                               }
+                                       }
                                }
-                       if ( i != 3 ) {
-                               continue;   // definately don't touch
-                       }
-                       fragments = Brush_Subtract( s, b );
-                       // if the brushes did not really intersect
-                       if ( fragments == s ) {
-                               continue;
-                       }
-                       // try to merge fragments
-                       fragments = Brush_MergeListPairs( fragments, true );
-                       // add the fragments to the list
-                       for ( frag = fragments; frag; frag = nextfragment )
-                       {
-                               nextfragment = frag->next;
-                               frag->next = NULL;
-                               frag->owner = s->owner;
-                               Brush_AddToList( frag, &fragmentlist );
-                       }
-                       // free the original brush
-                       Brush_Free( s );
-               }
-
-               // chop any active brushes up
-               for ( s = active_brushes.next; s != &active_brushes; s = snext )
-               {
-                       snext = s->next;
 
-                       if ( s->owner->eclass->fixedsize || s->patchBrush || s->bFiltered ) {
-                               continue;
-                       }
+                               // check faces already stored
+                               for ( Faces::const_iterator m = faces.begin(); !skip && m != faces.end(); ++m )
+                               {
+                                       const Face& face2 = *( *m );
 
-                       if ( s->brush_faces->pShader->getFlags() & QER_NOCARVE ) {
-                               continue;
-                       }
+                                       // face equals another face
+                                       if ( plane3_equal( face1.plane3(), face2.plane3() ) ) {
+                                               //if the texture/shader references should be the same but are not
+                                               if ( !onlyshape && !shader_equal( face1.getShader().getShader(), face2.getShader().getShader() ) ) {
+                                                       return false;
+                                               }
+                                               // skip duplicate planes
+                                               skip = true;
+                                               break;
+                                       }
 
-                       for ( i = 0 ; i < 3 ; i++ )
-                               if ( b->mins[i] >= s->maxs[i] - ON_EPSILON
-                                        || b->maxs[i] <= s->mins[i] + ON_EPSILON ) {
-                                       break;
+                                       // face1 plane intersects face2 winding or vice versa
+                                       if ( Winding_PlanesConcave( face1.getWinding(), face2.getWinding(), face1.plane3(), face2.plane3() ) ) {
+                                               // result would not be convex
+                                               return false;
+                                       }
                                }
-                       if ( i != 3 ) {
-                               continue;   // definately don't touch
 
+                               if ( !skip ) {
+                                       faces.push_back( &face1 );
+                               }
                        }
-                       fragments = Brush_Subtract( s, b );
-                       // if the brushes did not really intersect
-                       if ( fragments == s ) {
-                               continue;
-                       }
-                       //
-                       Undo_AddBrush( s );
-                       // one extra brush chopped up
-                       numbrushes++;
-                       // try to merge fragments
-                       fragments = Brush_MergeListPairs( fragments, true );
-                       // add the fragments to the list
-                       for ( frag = fragments; frag; frag = nextfragment )
-                       {
-                               nextfragment = frag->next;
-                               frag->next = NULL;
-                               frag->owner = s->owner;
-                               Brush_AddToList( frag, &fragmentlist );
+               }
+               for ( Faces::const_iterator i = faces.begin(); i != faces.end(); ++i )
+               {
+                       if ( !brush.addFace( *( *i ) ) ) {
+                               // result would have too many sides
+                               return false;
                        }
-                       // free the original brush
-                       Brush_Free( s );
                }
        }
 
-       // move all fragments to the active brush list
-       for ( frag = fragmentlist.next; frag != &fragmentlist; frag = nextfragment )
-       {
-               nextfragment = frag->next;
-               numfragments++;
-               Brush_RemoveFromList( frag );
-               Brush_AddToList( frag, &active_brushes );
-               Undo_EndBrush( frag );
-       }
+       brush.removeEmptyFaces();
 
-       /*if (numfragments == 0)
-          {
-           Sys_Printf("Selected brush%s did not intersect with any other brushes.\n",
-                       (selected_brushes.next->next == &selected_brushes) ? "":"es");
-           return;
-          }*/
-       Sys_Printf( "done. (created %d fragment%s out of %d brush%s)\n", numfragments, ( numfragments == 1 ) ? "" : "s",
-                               numbrushes, ( numbrushes == 1 ) ? "" : "es" );
-       Sys_UpdateWindows( W_ALL );
+       return true;
 }
 
-/*
-   =============
-   CSG_Merge
-   =============
- */
 void CSG_Merge( void ){
-       brush_t *b, *next, *newlist, *newbrush;
-       struct entity_s *owner;
+       brush_vector_t selected_brushes;
 
-       Sys_Printf( "Merging...\n" );
+       // remove selected
+       GlobalSceneGraph().traverse( BrushGatherSelected( selected_brushes ) );
 
-       if ( selected_brushes.next == &selected_brushes ) {
-               Sys_Printf( "No brushes selected.\n" );
+       if ( selected_brushes.empty() ) {
+               globalOutputStream() << "CSG Merge: No brushes selected.\n";
                return;
        }
 
-       if ( selected_brushes.next->next == &selected_brushes ) {
-               Sys_Printf( "At least two brushes have to be selected.\n" );
+       if ( selected_brushes.size() < 2 ) {
+               globalOutputStream() << "CSG Merge: At least two brushes have to be selected.\n";
                return;
        }
 
-       owner = selected_brushes.next->owner;
-
-       for ( b = selected_brushes.next; b != &selected_brushes; b = next )
-       {
-               next = b->next;
-
-               if ( b->owner->eclass->fixedsize ) {
-                       // can't use texture from a fixed entity, so don't subtract
-                       Sys_Printf( "Cannot add fixed size entities.\n" );
-                       return;
-               }
-
-               if ( b->patchBrush ) {
-                       Sys_Printf( "Cannot add patches.\n" );
-                       return;
-               }
-
-               // TTimo: cleanup
-               // disable the qer_nocarve for CSG-MERGE operations
-#if 0
-               if ( b->brush_faces->d_texture->bFromShader && ( b->brush_faces->d_texture->nShaderFlags & QER_NOCARVE ) ) {
-                       Sys_Printf( "Cannot add brushes using shaders that don't allows CSG operations.\n" );
-                       return;
-               }
-#endif
-
-               if ( b->owner != owner ) {
-                       Sys_Printf( "Cannot add brushes from different entities.\n" );
-                       return;
-               }
-
-       }
+       globalOutputStream() << "CSG Merge: Merging " << Unsigned( selected_brushes.size() ) << " brushes.\n";
 
-       newlist = NULL;
-       for ( b = selected_brushes.next; b != &selected_brushes; b = next )
-       {
-               next = b->next;
+       UndoableCommand undo( "brushMerge" );
 
-               Brush_RemoveFromList( b );
-               b->next = newlist;
-               b->prev = NULL;
-               newlist = b;
-       }
+       scene::Path merged_path = GlobalSelectionSystem().ultimateSelected().path();
 
-       newbrush = Brush_MergeList( newlist, true );
+       NodeSmartReference node( ( new BrushNode() )->node() );
+       Brush* brush = Node_getBrush( node );
        // if the new brush would not be convex
-       if ( !newbrush ) {
-               // add the brushes back into the selection
-               for ( b = newlist; b; b = next )
-               {
-                       next = b->next;
-                       b->next = NULL;
-                       b->prev = NULL;
-                       Brush_AddToList( b, &selected_brushes );
-               }
-               Sys_Printf( "Cannot add a set of brushes with a concave hull.\n" );
-               return;
+       if ( !Brush_merge( *brush, selected_brushes, true ) ) {
+               globalOutputStream() << "CSG Merge: Failed - result would not be convex.\n";
        }
-       // free the original brushes
-       for ( b = newlist; b; b = next )
+       else
        {
-               next = b->next;
-               b->next = NULL;
-               b->prev = NULL;
-               Brush_Free( b );
-       }
+               ASSERT_MESSAGE( !brush->empty(), "brush left with no faces after merge" );
 
-       newbrush->bFiltered = FilterBrush( newbrush ); // spog - set filters for the new brush
+               // free the original brushes
+               GlobalSceneGraph().traverse( BrushDeleteSelected() );
 
-       Brush_AddToList( newbrush, &selected_brushes );
+               merged_path.pop();
+               Node_getTraversable( merged_path.top() )->insert( node );
+               merged_path.push( makeReference( node.get() ) );
 
-       Sys_Printf( "done.\n" );
-       Sys_UpdateWindows( W_ALL );
+               selectPath( merged_path, true );
+
+               globalOutputStream() << "CSG Merge: Succeeded.\n";
+               SceneChangeNotify();
+       }
 }