BulletSim: Add one function that all actors who act on the physical

can use to know if the object is currently active.
Code cleaning including use of Util.ClampV function.

OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs

@@ -652,6 +652,9 @@ public sealed class BSCharacter : BSPhysObject
     public override bool IsStatic {
         get { return false; }
     }
+    public override bool IsPhysicallyActive {
+        get { return true; }
+    }
     public override bool Flying {
         get { return _flying; }
         set {

OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs

@@ -35,6 +35,7 @@ using System.Collections.Generic;
 using System.Reflection;
 using System.Runtime.InteropServices;
 using OpenMetaverse;
+using OpenSim.Framework;
 using OpenSim.Region.Physics.Manager;
 
 namespace OpenSim.Region.Physics.BulletSPlugin
@@ -154,7 +155,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
         // Return 'true' if this vehicle is doing vehicle things
         public bool IsActive
         {
-            get { return (Type != Vehicle.TYPE_NONE && !Prim.IsStatic); }
+            get { return (Type != Vehicle.TYPE_NONE && Prim.IsPhysicallyActive); }
         }
 
         #region Vehicle parameter setting

OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs

@@ -139,6 +139,11 @@ public abstract class BSPhysObject : PhysicsActor
     public abstract bool IsStatic { get; }
     public abstract bool IsSelected { get; }
 
+    // It can be confusing for an actor to know if it should move or update an object
+    //    depeneding on the setting of 'selected', 'physical, ...
+    // This flag is the true test -- if true, the object is being acted on in the physical world
+    public abstract bool IsPhysicallyActive { get; }
+
     // Materialness
     public MaterialAttributes.Material Material { get; private set; }
     public override void SetMaterial(int material)
@@ -302,8 +307,9 @@ public abstract class BSPhysObject : PhysicsActor
     public virtual bool SendCollisions()
     {
         bool ret = true;
+
         // If the 'no collision' call, force it to happen right now so quick collision_end
-        bool force = (CollisionCollection.Count == 0);
+        bool force = (CollisionCollection.Count == 0 && CollisionsLastTick.Count != 0);
 
         // throttle the collisions to the number of milliseconds specified in the subscription
         if (force || (PhysicsScene.SimulationNowTime >= NextCollisionOkTime))
@@ -318,7 +324,7 @@ public abstract class BSPhysObject : PhysicsActor
                 ret = false;
             }
 
-            // DetailLog("{0},{1}.SendCollisionUpdate,call,numCollisions={2}", LocalID, TypeName, CollisionCollection.Count);
+            DetailLog("{0},{1}.SendCollisionUpdate,call,numCollisions={2}", LocalID, TypeName, CollisionCollection.Count);
             base.SendCollisionUpdate(CollisionCollection);
 
             // Remember the collisions from this tick for some collision specific processing.

OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs

@@ -132,8 +132,8 @@ public sealed class BSPrim : BSPhysObject
         base.Destroy();
 
         // Undo any links between me and any other object
-        BSPhysObject parentBefore = Linkset.LinksetRoot;
-        int childrenBefore = Linkset.NumberOfChildren;
+        BSPhysObject parentBefore = Linkset.LinksetRoot;    // DEBUG DEBUG
+        int childrenBefore = Linkset.NumberOfChildren;      // DEBUG DEBUG
 
         Linkset = Linkset.RemoveMeFromLinkset(this);
 
@@ -727,6 +727,12 @@ public sealed class BSPrim : BSPhysObject
         get { return !IsPhantom && !_isVolumeDetect; }
     }
 
+    // The object is moving and is actively being dynamic in the physical world
+    public override bool IsPhysicallyActive
+    {
+        get { return !_isSelected && IsPhysical; }
+    }
+
     // Make gravity work if the object is physical and not selected
     // Called at taint-time!!
     private void SetObjectDynamic(bool forceRebuild)
@@ -1174,18 +1180,11 @@ public sealed class BSPrim : BSPhysObject
     // This added force will only last the next simulation tick.
     public void AddForce(OMV.Vector3 force, bool pushforce, bool inTaintTime) {
         // for an object, doesn't matter if force is a pushforce or not
-        if (!IsStatic)
+        if (IsPhysicallyActive)
         {
             if (force.IsFinite())
             {
-                float magnitude = force.Length();
-                if (magnitude > BSParam.MaxAddForceMagnitude)
-                {
-                    // Force has a limit
-                    force = force / magnitude * BSParam.MaxAddForceMagnitude;
-                }
-
-                OMV.Vector3 addForce = force;
+                OMV.Vector3 addForce = Util.ClampV(force, BSParam.MaxAddForceMagnitude);
                 // DetailLog("{0},BSPrim.addForce,call,force={1}", LocalID, addForce);
 
                 PhysicsScene.TaintedObject(inTaintTime, "BSPrim.AddForce", delegate()
@@ -1209,19 +1208,13 @@ public sealed class BSPrim : BSPhysObject
 
     public void AddForceImpulse(OMV.Vector3 impulse, bool pushforce, bool inTaintTime) {
         // for an object, doesn't matter if force is a pushforce or not
-        if (!IsStatic)
+        if (!IsPhysicallyActive)
         {
             if (impulse.IsFinite())
             {
-                float magnitude = impulse.Length();
-                if (magnitude > BSParam.MaxAddForceMagnitude)
-                {
-                    // Force has a limit
-                    impulse = impulse / magnitude * BSParam.MaxAddForceMagnitude;
-                }
-
+                OMV.Vector3 addImpulse = Util.ClampV(impulse, BSParam.MaxAddForceMagnitude);
                 // DetailLog("{0},BSPrim.addForceImpulse,call,impulse={1}", LocalID, impulse);
-                OMV.Vector3 addImpulse = impulse;
+
                 PhysicsScene.TaintedObject(inTaintTime, "BSPrim.AddImpulse", delegate()
                 {
                     // Bullet adds this impulse immediately to the velocity

OpenSim/Region/Physics/BulletSPlugin/BulletSimTODO.txt

@@ -16,6 +16,7 @@ vehicle angular banking
 Avatars walking up stairs (HALF DONE)
     Radius of the capsule affects ability to climb edges.
 Vehicle movement on terrain smoothness
+When is force introduced by SetForce removed? The prestep action could go forever.
 Boats float low in the water (DONE)
 Avatar movement
 	flying into a wall doesn't stop avatar who keeps appearing to move through the obstacle (DONE)
@@ -72,8 +73,11 @@ Incorporate inter-relationship of angular corrections. For instance, angularDefl
 
 GENERAL TODO LIST:
 =================================================
+Implement llSetPhysicalMaterial.
+Implement llSetForceAndTorque.
 Implement an avatar mesh shape. The Bullet capsule is way too limited.
 	Consider just hand creating a vertex/index array in a new BSShapeAvatar.
+Verify/fix phantom, volume-detect objects do not fall to infinity. Should stop at terrain.
 Revisit CollisionMargin. Builders notice the 0.04 spacing between prims.
 Duplicating a physical prim causes old prim to jump away
 	Dup a phys prim and the original become unselected and thus interacts w/ selected prim.
@@ -121,7 +125,7 @@ Physical and phantom will drop through the terrain
 LINKSETS
 ======================================================
 Editing a child of a linkset causes the child to go phantom
-	Move a child prim once when it is physical and can never move it again without it going phantom
+	Move a child prim once when it is physical and can never move it again without it going phantom
 Offset the center of the linkset to be the geometric center of all the prims
 	Not quite the same as the center-of-gravity
 Linksets should allow collisions to individual children