BGE: Occlusion culling and other performance improvements.

Added occlusion culling capability in the BGE. 
More info: http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.49/Game_Engine#BGE_Scenegraph_improvement
MSVC, scons, cmake, Makefile updated.

Other minor performance improvements:
- The rasterizer was computing the openGL model matrix of the objects too many times
- DBVT view frustrum culling was not properly culling behind the near plane:
  Large objects behind the camera were sent to the GPU
- Remove all references to mesh split/join feature as it is not yet functional

3 files changed, 8 insertions, 3 deletions

diff --git a/source/blender/makesdna/DNA_actuator_types.h b/source/blender/makesdna/DNA_actuator_types.h
index 2252126b46c..aeabae42adf 100644
--- a/source/blender/makesdna/DNA_actuator_types.h
+++ b/source/blender/makesdna/DNA_actuator_types.h
@@ -195,7 +195,8 @@ typedef struct bGameActuator {
 
 typedef struct bVisibilityActuator {
 	/** bit 0: Is this object visible? 
-	 ** bit 1: Apply recursively  */
+	 ** bit 1: Apply recursively  
+	 ** bit 2: Is this object an occluder? */
 	int flag;
 } bVisibilityActuator;
 
@@ -458,6 +459,7 @@ typedef struct FreeCamera {
 /* Set means the object will become invisible */
 #define ACT_VISIBILITY_INVISIBLE       (1 << 0)
 #define ACT_VISIBILITY_RECURSIVE       (1 << 1)
+#define ACT_VISIBILITY_OCCLUSION       (1 << 2)
 
 /* twodfilter->type */
 #define ACT_2DFILTER_ENABLED			-2
diff --git a/source/blender/makesdna/DNA_object_types.h b/source/blender/makesdna/DNA_object_types.h
index b17896aec70..3a408404b0b 100644
--- a/source/blender/makesdna/DNA_object_types.h
+++ b/source/blender/makesdna/DNA_object_types.h
@@ -437,6 +437,7 @@ extern Object workob;
 
 #define OB_COLLISION	65536
 #define OB_SOFT_BODY	0x20000
+#define OB_OCCLUDER		0x40000
 
 /* ob->gameflag2 */
 #define OB_NEVER_DO_ACTIVITY_CULLING	1
@@ -455,6 +456,7 @@ extern Object workob;
 #define OB_BODY_TYPE_DYNAMIC		2
 #define OB_BODY_TYPE_RIGID			3
 #define OB_BODY_TYPE_SOFT			4
+#define OB_BODY_TYPE_OCCLUDER		5
 
 /* ob->scavisflag */
 #define OB_VIS_SENS		1
diff --git a/source/blender/makesdna/DNA_world_types.h b/source/blender/makesdna/DNA_world_types.h
index a51e9704be2..f599364ed66 100644
--- a/source/blender/makesdna/DNA_world_types.h
+++ b/source/blender/makesdna/DNA_world_types.h
@@ -88,7 +88,8 @@ typedef struct World {
 	 * bit 5: (gameengine) : enable Bullet DBVT tree for view frustrum culling 
 	 */
 	short mode;
-	int physicsEngine;	/* here it's aligned */
+	short occlusionRes;		/* resolution of occlusion Z buffer in pixel */
+	short physicsEngine;	/* here it's aligned */
 	
 	float misi, miststa, mistdist, misthi;
 	
@@ -135,7 +136,7 @@ typedef struct World {
 #define WO_DOF                 4
 #define WO_ACTIVITY_CULLING	   8
 #define WO_AMB_OCC	   		  16
-#define WO_DBVT_CAMERA_CULLING  32
+#define WO_DBVT_CULLING		  32
 
 /* aomix */
 #define WO_AOADD	0