Recursive portal culling is implemented. This is the 3rd phase. There is one bug where portals are behaving weird when camera is right on the portal plane

panda/src/pgraph/portalClipper.I

@@ -101,24 +101,43 @@ draw_camera_frustum() {
 }
 
 ////////////////////////////////////////////////////////////////////
-//     Function: PortalClipper::set_reduced_frustum
+//     Function: PortalClipper::set_view_frustum
 //       Access: Public
-//  Description: set the current reduced frustum before traversing
+//  Description: set the current view frustum before traversing
 //           
 ////////////////////////////////////////////////////////////////////
 INLINE void PortalClipper::
-set_reduced_frustum(BoundingHexahedron *frustum) {
-  _reduced_frustum = frustum;
+set_view_frustum(BoundingHexahedron *frustum) {
+  _view_frustum = frustum;
 }
+
+////////////////////////////////////////////////////////////////////
+//     Function: PortalClipper::is_facing_view
+//       Access: Public
+//  Description: checks if the portal plane (in camera space)
+//               is facing the camera's near plane
+////////////////////////////////////////////////////////////////////
+INLINE bool PortalClipper::
+is_facing_view(Planef portal_plane)
+{
+  Planef view_plane(_view_frustum->get_point(4), _view_frustum->get_point(5), _view_frustum->get_point(6));
+
+  // use the view_frustum's near plane to calculate direction
+  pgraph_cat.debug() << portal_plane.get_normal() << "; " << -view_plane.get_normal() << endl;
+  float direction = portal_plane.get_normal().dot(-view_plane.get_normal());
+  pgraph_cat.debug() << "Found direction of " << direction << endl;
+  return (direction < _FACING_THRESHOLD);
+}
+
 ////////////////////////////////////////////////////////////////////
-//     Function: PortalClipper::is_in_view
+//     Function: PortalClipper::is_whole_portal_in_view
 //       Access: Public
 //  Description: checks if portal_node is within the view frustum.
 //               If so, then the portal is worth considering. This
 //               is a 1st level test to weed out most of the portals
 ////////////////////////////////////////////////////////////////////
 INLINE bool PortalClipper::
-is_in_view(const NodePath &node_path) {
+is_whole_portal_in_view(const NodePath &node_path) {
 
   const BoundingVolume *bv = &_portal_node->get_bound();
 
@@ -130,27 +149,28 @@ is_in_view(const NodePath &node_path) {
   CPT(TransformState) ctransform = node_path.get_transform(_scene_setup->get_cull_center());
   gbv->xform(ctransform->get_mat());
 
-  int result = _reduced_frustum->contains(gbv);
-  pgraph_cat.debug() << "1st level test if portal is in view " << result << endl;
+  int result = _view_frustum->contains(gbv);
+
+  pgraph_cat.debug() << "1st level test if portal: " << *_view_frustum << " is in view " << result << endl;
   return (result != 0);
 }
 
 ////////////////////////////////////////////////////////////////////
-//     Function: PortalClipper::facing_camera
+//     Function: PortalClipper::is_partial_portal_in_view
 //       Access: Public
 //  Description: checks if any of the _coords is within the view frustum.
 //               If so, then the portal is facing the camera. 2nd level
 //               test to make sure this portal is worth visiting
 ////////////////////////////////////////////////////////////////////
 INLINE bool PortalClipper::
-is_facing_camera(const NodePath &node_path) {
+is_partial_portal_in_view(const NodePath &node_path) {
   int result = 0;
 
-  // check if the camera_center to portal_center lineseg is in view
+  // check if any of the _coords in tested frustum
   for (int j=0; j<_num_vert; ++j) {
-    result |= _reduced_frustum->contains(_coords[j]);
+    result |= _view_frustum->contains(_coords[j]);
   }
-  pgraph_cat.debug() << "frustum->contains(coord) result = " << result << endl;
+  pgraph_cat.debug() << "frustum: " << *_view_frustum << " contains(coord) result = " << result << endl;
 
   return (result != 0);
 }

panda/src/pgraph/portalClipper.cxx

@@ -47,7 +47,7 @@ PortalClipper(GeometricBoundingVolume *frustum, SceneSetup *scene_setup) {
   _geom_point = new GeomPoint;
   _geom_linestrip = new GeomLinestrip;
 
-  _view_frustum = _reduced_frustum = DCAST(BoundingHexahedron, frustum);
+  _view_frustum = DCAST(BoundingHexahedron, frustum);
 
   _scene_setup = scene_setup;
 }
@@ -260,6 +260,10 @@ prepare_portal(const NodePath &node_path)
   temp[2] = temp[2]*cmat;
   temp[3] = temp[3]*cmat;
 
+  Planef portal_plane(temp[0], temp[1], temp[2]);
+  if (!is_facing_view(portal_plane))
+    return;
+
   pgraph_cat.spam() << "after transformation to camera space" << endl;
   pgraph_cat.spam() << temp[0] << endl;
   pgraph_cat.spam() << temp[1] << endl;
@@ -275,9 +279,6 @@ prepare_portal(const NodePath &node_path)
 
   pgraph_cat.spam() << "min_x " << min_x << ";max_x " << max_x << ";min_z " << min_z << ";max_z " << max_z << endl;
 
-
-  Planef portal_plane(temp[0], temp[1], temp[2]);
-
   float y;
 
   y = get_plane_depth(min_x, min_z, &portal_plane);
@@ -303,7 +304,7 @@ prepare_portal(const NodePath &node_path)
   pgraph_cat.spam() << _coords[3] << endl;
 
   // check if portal is in view
-  if (is_in_view(node_path)) {
+  if (is_whole_portal_in_view(node_path)) {
     pgraph_cat.debug() << "portal passed 1st level test \n";
     
     // ok, now lets add the original portal
@@ -376,7 +377,7 @@ clip_portal(const NodePath &node_path)
     from_direction = _coords[(j+1)%_num_vert] - _coords[j];
     is_intersect = plane.intersects_line(t, from_origin, from_direction);
     if (is_intersect && (t > 0.0 && t < 1.0)) {
-      pgraph_cat.debug() << "bottom plane intersected segement " << j << "->" 
+      pgraph_cat.debug() << "bottom plane intersected segment " << j << "->" 
                          << (j+1)%_num_vert << " at t=" << t << endl;
       cut_point = from_origin + t*from_direction;
       pgraph_cat.debug() << "cut_point: " << cut_point << endl;
@@ -400,7 +401,7 @@ clip_portal(const NodePath &node_path)
     from_direction = _coords[(j+1)%_num_vert] - _coords[j];
     is_intersect = plane.intersects_line(t, from_origin, from_direction);
     if (is_intersect && (t > 0.0 && t < 1.0)) {
-      pgraph_cat.debug() << "top plane intersected segement " << j << "->" 
+      pgraph_cat.debug() << "top plane intersected segment " << j << "->" 
                          << (j+1)%_num_vert << " at t=" << t << endl;
       cut_point = from_origin + t*from_direction;
       pgraph_cat.debug() << "cut_point: " << cut_point << endl;
@@ -424,7 +425,7 @@ clip_portal(const NodePath &node_path)
     from_direction = _coords[(j+1)%_num_vert] - _coords[j];
     is_intersect = plane.intersects_line(t, from_origin, from_direction);
     if (is_intersect && (t > 0.0 && t < 1.0)) {
-      pgraph_cat.debug() << "right plane intersected segement " << j << "->" 
+      pgraph_cat.debug() << "right plane intersected segment " << j << "->" 
                          << (j+1)%_num_vert << " at t=" << t << endl;
       cut_point = from_origin + t*from_direction;
       pgraph_cat.debug() << "cut_point: " << cut_point << endl;
@@ -448,7 +449,7 @@ clip_portal(const NodePath &node_path)
     from_direction = _coords[(j+1)%_num_vert] - _coords[j];
     is_intersect = plane.intersects_line(t, from_origin, from_direction);
     if (is_intersect && (t > 0.0 && t < 1.0)) {
-      pgraph_cat.debug() << "left plane intersected segement " << j << "->" 
+      pgraph_cat.debug() << "left plane intersected segment " << j << "->" 
                          << (j+1)%_num_vert << " at t=" << t << endl;
       cut_point = from_origin + t*from_direction;
       pgraph_cat.debug() << "cut_point: " << cut_point << endl;
@@ -473,7 +474,7 @@ clip_portal(const NodePath &node_path)
   draw_to(_coords[0]);
 
   // 2nd level test, more accurate to determine if the portal is worth visiting
-  if (!is_facing_camera(node_path)) {
+  if (!is_partial_portal_in_view(node_path)) {
     pgraph_cat.debug() << "portal failed 2nd level test \n";
     _num_vert = 0;
   }
@@ -562,13 +563,11 @@ get_reduced_frustum(const NodePath &node_path)
                        _view_frustum->get_point(4), _view_frustum->get_point(5),
                        _view_frustum->get_point(6), _view_frustum->get_point(7));
 
-  pgraph_cat.spam() << *reduced_frustum << endl;
+  pgraph_cat.debug() << *reduced_frustum << endl;
 
   // draw this hexahedron
   _color = Colorf(0,0,1,1);
   draw_hexahedron(DCAST(BoundingHexahedron, reduced_frustum));
 
-  _reduced_frustum = DCAST(BoundingHexahedron, reduced_frustum);
-
   return reduced_frustum;
 }

panda/src/pgraph/portalClipper.h

@@ -63,12 +63,12 @@ public:
   PortalClipper(GeometricBoundingVolume *frustum, SceneSetup *scene_setup);
   ~PortalClipper();
 
-  INLINE bool is_in_view(const NodePath &node_path);
-  INLINE bool is_facing_camera(const NodePath &node_path);
-  void prepare_portal(const NodePath &node_path);
+  INLINE bool is_whole_portal_in_view(const NodePath &node_path);
+  INLINE bool is_partial_portal_in_view(const NodePath &node_path);
+  INLINE bool is_facing_view(Planef portal_plane);
 
+  void prepare_portal(const NodePath &node_path);
   void clip_portal(const NodePath &node_path);
-
   PT(BoundingVolume) get_reduced_frustum(const NodePath &node_path);
 
   void draw_lines();
@@ -83,7 +83,7 @@ public:
 
   INLINE float get_plane_depth(float x, float z, Planef *portal_plane);
 
-  INLINE void  set_reduced_frustum(BoundingHexahedron *frustum);
+  INLINE void  set_view_frustum(BoundingHexahedron *frustum);
 
 public:
   static TypeHandle get_class_type() {
@@ -129,7 +129,6 @@ private:
   PT(GeomLinestrip) _geom_linestrip;
 
   BoundingHexahedron *_view_frustum;
-  BoundingHexahedron *_reduced_frustum;
 
   PortalNode *_portal_node;  // current working portal for dereference ease
 

panda/src/pgraph/portalNode.cxx

@@ -48,7 +48,7 @@ PortalNode(const string &name) :
 {
   _zone_in = NULL;
   _zone_out = NULL;
-  _visible = false;
+  _visible = true;
 }
 
 ////////////////////////////////////////////////////////////////////
@@ -65,7 +65,7 @@ PortalNode(const PortalNode &copy) :
 {
   _zone_in = NULL;
   _zone_out = NULL;
-  _visible = false;
+  _visible = true;
 }
 
 ////////////////////////////////////////////////////////////////////
@@ -180,28 +180,30 @@ cull_callback(CullTraverser *trav, CullTraverserData &data) {
   PortalClipper *portal_viewer = trav->get_portal_clipper();
   if (!_zone_out.is_empty() && portal_viewer) {
     //CullTraverserData next_data(data, _zone_out);
-    if (is_visible()) {
-      pgraph_cat.debug() << "portal node visible " << *this << endl;
-      PT(GeometricBoundingVolume) vf = trav->get_view_frustum();
-      PT(BoundingVolume) reduced_frustum;
+    pgraph_cat.debug() << "checking portal node  " << *this << endl;
+    PT(GeometricBoundingVolume) vf = trav->get_view_frustum();
+    PT(BoundingVolume) reduced_frustum;
+     
+    // following three functions do nothing, if the portal is not visible
+    portal_viewer->prepare_portal(data._node_path.get_node_path());
+    portal_viewer->clip_portal(data._node_path.get_node_path());
+    if ((reduced_frustum = portal_viewer->get_reduced_frustum(data._node_path.get_node_path()))) {
+      // This reduced frustum is in camera space
+      pgraph_cat.debug() << "got reduced frustum " << reduced_frustum << endl;
+      vf = DCAST(GeometricBoundingVolume, reduced_frustum);
+      
+      portal_viewer->set_view_frustum(DCAST(BoundingHexahedron,vf->make_copy()));
+      
+      // trasform it to cull_center space
+      CPT(TransformState) cull_center_transform = 
+        portal_viewer->_scene_setup->get_cull_center().get_transform(_zone_out);
+      vf->xform(cull_center_transform->get_mat());
       
-      portal_viewer->prepare_portal(data._node_path.get_node_path());
-      portal_viewer->clip_portal(data._node_path.get_node_path());
-      if ((reduced_frustum = portal_viewer->get_reduced_frustum(data._node_path.get_node_path()))) {
-        // This reduced frustum is in camera space
-        pgraph_cat.debug() << "got reduced frustum " << reduced_frustum << endl;
-        vf = DCAST(GeometricBoundingVolume, reduced_frustum);
-        
-        // trasform it to cull_center space
-        CPT(TransformState) cull_center_transform = 
-          portal_viewer->_scene_setup->get_cull_center().get_transform(_zone_out);
-        vf->xform(cull_center_transform->get_mat());
-      }
       pgraph_cat.spam() << "vf is " << *vf << "\n";
-
+    
       // Get the net trasform of the _zone_out
       CPT(TransformState) zone_transform = _zone_out.get_net_transform();
-
+      
       CullTraverserData next_data(_zone_out, trav->get_render_transform()->compose(zone_transform),
                                   zone_transform,
                                   trav->get_initial_state(), vf,