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.

0.7.5-pf-bulletsim
Robert Adams 2012-12-21 10:00:03 -08:00
parent b4f8a05e9a
commit 8c99f63239
2 changed files with 81 additions and 4 deletions

View File

@ -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);

View File

@ -532,15 +532,17 @@ 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;
if (PhysBody.HasPhysicalBody)
BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity);
}
}