From 8c99f63239702bcdb8f1e0efa57efc91c98fc3d7 Mon Sep 17 00:00:00 2001 From: Robert Adams Date: Fri, 21 Dec 2012 10:00:03 -0800 Subject: BulletSim: avatar movement smoothed with motor that modifies avatar velocity to target velocity. Fails in incorporating physical world effects (gravity) so avatar doesn't fly correctly. --- .../Region/Physics/BulletSPlugin/BSCharacter.cs | 77 +++++++++++++++++++++- OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs | 8 ++- 2 files changed, 81 insertions(+), 4 deletions(-) diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs index 4dd6264..695896e 100644 --- a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs +++ b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs @@ -69,6 +69,8 @@ public sealed class BSCharacter : BSPhysObject private OMV.Vector3 _appliedVelocity; // the last velocity applied to the avatar private float _currentFriction; // the friction currently being used (changed by setVelocity). + private BSVMotor _velocityMotor; + private OMV.Vector3 _PIDTarget; private bool _usePID; private float _PIDTau; @@ -89,6 +91,18 @@ public sealed class BSCharacter : BSPhysObject if (_size.X == 0f) _size.X = PhysicsScene.Params.avatarCapsuleDepth; if (_size.Y == 0f) _size.Y = PhysicsScene.Params.avatarCapsuleWidth; + // A motor to control the acceleration and deceleration of the avatar movement. + // _velocityMotor = new BSVMotor("BSCharacter.Velocity", 3f, 5f, BSMotor.InfiniteVector, 1f); + // _velocityMotor = new BSPIDVMotor("BSCharacter.Velocity", 3f, 5f, BSMotor.InfiniteVector, 1f); + // Infinite decay and timescale values so motor only changes current to target values. + _velocityMotor = new BSVMotor("BSCharacter.Velocity", + 0.2f, // time scale + BSMotor.Infinite, // decay time scale + BSMotor.InfiniteVector, // friction timescale + 1f // efficiency + ); + _velocityMotor.PhysicsScene = PhysicsScene; // DEBUG DEBUG so motor will output detail log messages. + _flying = isFlying; _orientation = OMV.Quaternion.Identity; _velocity = OMV.Vector3.Zero; @@ -138,6 +152,10 @@ public sealed class BSCharacter : BSPhysObject ForcePosition = _position; // Set the velocity and compute the proper friction ForceVelocity = _velocity; + // Setting the current and target in the motor will cause it to start computing any deceleration. + _velocityMotor.Reset(); + _velocityMotor.SetCurrent(_velocity); + _velocityMotor.SetTarget(_velocity); // This will enable or disable the flying buoyancy of the avatar. // Needs to be reset especially when an avatar is recreated after crossing a region boundry. @@ -239,6 +257,7 @@ public sealed class BSCharacter : BSPhysObject public override void ZeroMotion(bool inTaintTime) { _velocity = OMV.Vector3.Zero; + _velocityMotor.Zero(); _acceleration = OMV.Vector3.Zero; _rotationalVelocity = OMV.Vector3.Zero; @@ -400,10 +419,38 @@ public sealed class BSCharacter : BSPhysObject public override OMV.Vector3 GeometricCenter { get { return OMV.Vector3.Zero; } } public override OMV.Vector3 CenterOfMass { get { return OMV.Vector3.Zero; } } + + // Sets the target in the motor. This starts the changing of the avatar's velocity. + public override OMV.Vector3 TargetVelocity + { + get + { + return _velocityMotor.TargetValue; + } + set + { + DetailLog("{0},BSCharacter.setTargetVelocity,call,vel={1}", LocalID, value); + OMV.Vector3 targetVel = value; + PhysicsScene.TaintedObject("BSCharacter.setTargetVelocity", delegate() + { + float timeStep = 0.089f; // DEBUG DEBUG FIX FIX FIX + _velocityMotor.Reset(); + _velocityMotor.SetTarget(targetVel); + _velocityMotor.SetCurrent(_velocity); + // Compute a velocity value and make sure it gets pushed into the avatar. + // This makes sure the avatar will start from a stop. + ForceVelocity = _velocityMotor.Step(timeStep); + }); + } + } + // Directly setting velocity means this is what the user really wants now. public override OMV.Vector3 Velocity { get { return _velocity; } set { _velocity = value; + _velocityMotor.Reset(); + _velocityMotor.SetCurrent(_velocity); + _velocityMotor.SetTarget(_velocity); // m_log.DebugFormat("{0}: set velocity = {1}", LogHeader, _velocity); PhysicsScene.TaintedObject("BSCharacter.setVelocity", delegate() { @@ -415,6 +462,8 @@ public sealed class BSCharacter : BSPhysObject public override OMV.Vector3 ForceVelocity { get { return _velocity; } set { + PhysicsScene.AssertInTaintTime("BSCharacter.ForceVelocity"); + // Depending on whether the avatar is moving or not, change the friction // to keep the avatar from slipping around if (_velocity.Length() == 0) @@ -511,6 +560,13 @@ public sealed class BSCharacter : BSPhysObject get { return _flying; } set { _flying = value; + + // Velocity movement is different when flying: flying velocity degrades over time. + if (_flying) + _velocityMotor.TargetValueDecayTimeScale = 1f; + else + _velocityMotor.TargetValueDecayTimeScale = BSMotor.Infinite; + // simulate flying by changing the effect of gravity Buoyancy = ComputeBuoyancyFromFlying(_flying); } @@ -581,7 +637,10 @@ public sealed class BSCharacter : BSPhysObject } public override float ForceBuoyancy { get { return _buoyancy; } - set { _buoyancy = value; + set { + PhysicsScene.AssertInTaintTime("BSCharacter.ForceBuoyancy"); + + _buoyancy = value; DetailLog("{0},BSCharacter.setForceBuoyancy,taint,buoy={1}", LocalID, _buoyancy); // Buoyancy is faked by changing the gravity applied to the object float grav = PhysicsScene.Params.gravity * (1f - _buoyancy); @@ -698,6 +757,21 @@ public sealed class BSCharacter : BSPhysObject LastEntityProperties = CurrentEntityProperties; CurrentEntityProperties = entprop; + // Avatars don't respond to world friction, etc. They only go the speed I tell them too. + // Special kludge here for falling. Even though the target velocity might not have a + // Z component, the avatar could be falling (walked off a ledge, stopped flying, ...) + // and that velocity component must be retained. + float timeStep = 0.089f; // DEBUG DEBUG FIX FIX FIX + OMV.Vector3 stepVelocity = _velocityMotor.Step(timeStep); + stepVelocity.Z += entprop.Velocity.Z; + _velocity = stepVelocity; + BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity); + /* + OMV.Vector3 stepVelocity = _velocityMotor.Step(timeStep); + OMV.Vector3 avVel = new OMV.Vector3(stepVelocity.X, stepVelocity.Y, entprop.Velocity.Z); + _velocity = avVel; + BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, avVel); + if (entprop.Velocity != LastEntityProperties.Velocity) { // Changes in the velocity are suppressed in avatars. @@ -706,6 +780,7 @@ public sealed class BSCharacter : BSPhysObject _velocity = avVel; BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, avVel); } + */ // Tell the linkset about value changes Linkset.UpdateProperties(this, true); diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs index 1c6f946..68a0db6 100644 --- a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs +++ b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs @@ -532,16 +532,18 @@ public sealed class BSPrim : BSPhysObject PhysicsScene.TaintedObject("BSPrim.setVelocity", delegate() { // DetailLog("{0},BSPrim.SetVelocity,taint,vel={1}", LocalID, _velocity); - if (PhysBody.HasPhysicalBody) - BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity); + ForceVelocity = _velocity; }); } } public override OMV.Vector3 ForceVelocity { get { return _velocity; } set { + PhysicsScene.AssertInTaintTime("BSPrim.ForceVelocity"); + _velocity = value; - BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity); + if (PhysBody.HasPhysicalBody) + BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity); } } public override OMV.Vector3 Torque { -- cgit v1.1