Upgraded to Bullet 2.74. The upgrade introduced a few bugs, which need to be fixed before Blender 2.49.

In particular, the Bullet vehicle seems broken, and some soft-body demos don't work.
No new features or benefits are added yet, but a few improvements are planned before Blender 2.49 release.

Please update the build systems, and add those 3 files:
extern/bullet2/src/BulletCollision/CollisionDispatch/btActivatingCollisionAlgorithm.cpp
extern/bullet2/src/BulletCollision/CollisionDispatch/btGhostObject.cpp
extern/bullet2/src/BulletCollision/CollisionShapes/btConvexPointCloudShape.cpp

I'll watch the Blender mailing list, in case this commit causes some issues.

1 files changed, 13 insertions, 3 deletions

diff --git a/extern/bullet2/src/BulletDynamics/ConstraintSolver/btContactSolverInfo.h b/extern/bullet2/src/BulletDynamics/ConstraintSolver/btContactSolverInfo.h
index 916d4581f79..e99430c00de 100644
--- a/extern/bullet2/src/BulletDynamics/ConstraintSolver/btContactSolverInfo.h
+++ b/extern/bullet2/src/BulletDynamics/ConstraintSolver/btContactSolverInfo.h
@@ -21,7 +21,13 @@ enum	btSolverMode
 	SOLVER_RANDMIZE_ORDER = 1,
 	SOLVER_FRICTION_SEPARATE = 2,
 	SOLVER_USE_WARMSTARTING = 4,
-	SOLVER_CACHE_FRIENDLY = 8
+	SOLVER_USE_FRICTION_WARMSTARTING = 8,
+	SOLVER_USE_2_FRICTION_DIRECTIONS = 16,
+	SOLVER_ENABLE_FRICTION_DIRECTION_CACHING = 32,
+	SOLVER_DISABLE_VELOCITY_DEPENDENT_FRICTION_DIRECTION = 64,
+	SOLVER_CACHE_FRIENDLY = 128,
+	SOLVER_SIMD = 256,	//enabled for Windows, the solver innerloop is branchless SIMD, 40% faster than FPU/scalar version
+	SOLVER_CUDA = 512	//will be open sourced during Game Developers Conference 2009. Much faster.
 };
 
 struct btContactSolverInfoData
@@ -38,12 +44,14 @@ struct btContactSolverInfoData
 	btScalar	m_sor;
 	btScalar	m_erp;//used as Baumgarte factor
 	btScalar	m_erp2;//used in Split Impulse
+	btScalar	m_globalCfm;//constraint force mixing
 	int			m_splitImpulse;
 	btScalar	m_splitImpulsePenetrationThreshold;
 	btScalar	m_linearSlop;
 	btScalar	m_warmstartingFactor;
 
 	int			m_solverMode;
+	int	m_restingContactRestitutionThreshold;
 
 
 };
@@ -63,12 +71,14 @@ struct btContactSolverInfo : public btContactSolverInfoData
 		m_numIterations = 10;
 		m_erp = btScalar(0.2);
 		m_erp2 = btScalar(0.1);
-		m_sor = btScalar(1.3);
+		m_globalCfm = btScalar(0.);
+		m_sor = btScalar(1.);
 		m_splitImpulse = false;
 		m_splitImpulsePenetrationThreshold = -0.02f;
 		m_linearSlop = btScalar(0.0);
 		m_warmstartingFactor=btScalar(0.85);
-		m_solverMode = SOLVER_RANDMIZE_ORDER | SOLVER_CACHE_FRIENDLY | SOLVER_USE_WARMSTARTING;
+		m_solverMode = SOLVER_USE_WARMSTARTING | SOLVER_SIMD ;//SOLVER_RANDMIZE_ORDER
+		m_restingContactRestitutionThreshold = 2;//resting contact lifetime threshold to disable restitution
 	}
 };