BulletSim: More aggressive as setting character velocity to zero

when should be standing.
Modify angular force routines to be the same pattern as linear force routines.
BulletSim vehicle turning is scaled like SL and is DIFFERENT THAN ODE!!
Fix some bugs in BSMotor dealing with the motor going to zero.
Add a bunch of parameters:  MaxLinearVelocity, MaxAngularVelocity,
MaxAddForceMagnitude, VehicleMaxLinearVelocity, VehicleMaxAngularVelocity,
and most of the values are defaulted to values that are larger
than in SL.
Use the new parameters in BSPrim, BSCharacter and BSDynamic.

1 files changed, 23 insertions, 7 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
index cd279e3..a9e16e6 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
@@ -200,20 +200,36 @@ public sealed class BSCharacter : BSPhysObject
             // TODO: Decide if the step parameters should be changed depending on the avatar's
             //     state (flying, colliding, ...). There is code in ODE to do this.
 
+            // COMMENTARY: when the user is making the avatar walk, except for falling, the velocity
+            //   specified for the avatar is the one that should be used. For falling, if the avatar
+            //   is not flying and is not colliding then it is presumed to be falling and the Z
+            //   component is not fooled with (thus allowing gravity to do its thing).
+            // When the avatar is standing, though, the user has specified a velocity of zero and
+            //   the avatar should be standing. But if the avatar is pushed by something in the world
+            //   (raising elevator platform, moving vehicle, ...) the avatar should be allowed to
+            //   move. Thus, the velocity cannot be forced to zero. The problem is that small velocity
+            //   errors can creap in and the avatar will slowly float off in some direction.
+            // So, the problem is that, when an avatar is standing, we cannot tell creaping error
+            //   from real pushing.OMV.Vector3.Zero;
+            // The code below keeps setting the velocity to zero hoping the world will keep pushing.
+
             _velocityMotor.Step(timeStep);
 
             // If we're not supposed to be moving, make sure things are zero.
-            if (_velocityMotor.ErrorIsZero() && _velocityMotor.TargetValue.ApproxEquals(OMV.Vector3.Zero, 0.01f))
+            if (_velocityMotor.ErrorIsZero() && _velocityMotor.TargetValue == OMV.Vector3.Zero && IsColliding)
             {
-                if (_wasWalking)
+                // The avatar shouldn't be moving
+                _velocityMotor.Zero();
+                ZeroMotion(true /* inTaintTime */);
+
+                // Standing has more friction on the ground
+                if (_currentFriction != BSParam.AvatarStandingFriction)
                 {
-                    _velocityMotor.Zero();
-                    _velocity = OMV.Vector3.Zero;
-                    PhysicsScene.PE.SetLinearVelocity(PhysBody, OMV.Vector3.Zero);
                     _currentFriction = BSParam.AvatarStandingFriction;
                     PhysicsScene.PE.SetFriction(PhysBody, _currentFriction);
-                    // DetailLog("{0},BSCharacter.MoveMotor,taint,stopping,target={1}", LocalID, _velocityMotor.TargetValue);
                 }
+                DetailLog("{0},BSCharacter.MoveMotor,taint,stopping,target={1}", LocalID, _velocityMotor.TargetValue);
+
                 _wasWalking = false;
             }
             else
@@ -242,7 +258,7 @@ public sealed class BSCharacter : BSPhysObject
                 // Add special movement force to allow avatars to walk up stepped surfaces.
                 moveForce += WalkUpStairs();
 
-                // DetailLog("{0},BSCharacter.MoveMotor,move,stepVel={1},vel={2},mass={3},moveForce={4}", LocalID, stepVelocity, _velocity, Mass, moveForce);
+                DetailLog("{0},BSCharacter.MoveMotor,move,stepVel={1},vel={2},mass={3},moveForce={4}", LocalID, stepVelocity, _velocity, Mass, moveForce);
                 PhysicsScene.PE.ApplyCentralImpulse(PhysBody, moveForce);
                 _wasWalking = true;
             }