BulletSim: add comments to force and impulse setting functions

so it is clear what Bullet is actually doing with the set values.

1 files changed, 8 insertions, 0 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSAPIUnman.cs b/OpenSim/Region/Physics/BulletSPlugin/BSAPIUnman.cs
index 45ecf56..14de2eb 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSAPIUnman.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSAPIUnman.cs
@@ -921,6 +921,7 @@ public override void SetCenterOfMassByPosRot(BulletBody obj, Vector3 pos, Quater
 }
 
 // Add a force to the object as if its mass is one.
+// Deep down in Bullet: m_totalForce += force*m_linearFactor;
 public override void ApplyCentralForce(BulletBody obj, Vector3 force)
 {
     BulletBodyUnman bodyu = obj as BulletBodyUnman;
@@ -964,6 +965,7 @@ public override void SetSleepingThresholds(BulletBody obj, float lin_threshold,
     BSAPICPP.SetSleepingThresholds2(bodyu.ptr, lin_threshold, ang_threshold);
 }
 
+// Deep down in Bullet: m_totalTorque += torque*m_angularFactor;
 public override void ApplyTorque(BulletBody obj, Vector3 torque)
 {
     BulletBodyUnman bodyu = obj as BulletBodyUnman;
@@ -971,6 +973,8 @@ public override void ApplyTorque(BulletBody obj, Vector3 torque)
 }
 
 // Apply force at the given point. Will add torque to the object.
+// Deep down in Bullet: applyCentralForce(force);
+//                              applyTorque(rel_pos.cross(force*m_linearFactor));
 public override void ApplyForce(BulletBody obj, Vector3 force, Vector3 pos)
 {
     BulletBodyUnman bodyu = obj as BulletBodyUnman;
@@ -978,6 +982,7 @@ public override void ApplyForce(BulletBody obj, Vector3 force, Vector3 pos)
 }
 
 // Apply impulse to the object. Same as "ApplycentralForce" but force scaled by object's mass.
+// Deep down in Bullet: m_linearVelocity += impulse *m_linearFactor * m_inverseMass;
 public override void ApplyCentralImpulse(BulletBody obj, Vector3 imp)
 {
     BulletBodyUnman bodyu = obj as BulletBodyUnman;
@@ -985,6 +990,7 @@ public override void ApplyCentralImpulse(BulletBody obj, Vector3 imp)
 }
 
 // Apply impulse to the object's torque. Force is scaled by object's mass.
+// Deep down in Bullet: m_angularVelocity += m_invInertiaTensorWorld * torque * m_angularFactor;
 public override void ApplyTorqueImpulse(BulletBody obj, Vector3 imp)
 {
     BulletBodyUnman bodyu = obj as BulletBodyUnman;
@@ -992,6 +998,8 @@ public override void ApplyTorqueImpulse(BulletBody obj, Vector3 imp)
 }
 
 // Apply impulse at the point given. For is scaled by object's mass and effects both linear and angular forces.
+// Deep down in Bullet: applyCentralImpulse(impulse);
+//                              applyTorqueImpulse(rel_pos.cross(impulse*m_linearFactor));
 public override void ApplyImpulse(BulletBody obj, Vector3 imp, Vector3 pos)
 {
     BulletBodyUnman bodyu = obj as BulletBodyUnman;