void IBeforeSolverUpdateable.Update(float dt)
{
//We can't let multiple characters manage the same pairs simultaneously. Lock it up!
this.LockCharacterPairs();
try
{
bool hadSupport = this.SupportFinder.HasSupport;
this.CollectSupportData();
//Compute the initial velocities relative to the support.
var relativeVelocity = this.Body.LinearVelocity;
var verticalVelocity = Vector3.Dot(this.supportData.Normal, relativeVelocity);
//Don't attempt to use an object as support if we are flying away from it (and we were never standing on it to begin with).
if (this.SupportFinder.HasSupport && !hadSupport && verticalVelocity < 0)
{
this.SupportFinder.ClearSupportData();
this.supportData = new SupportData();
}
//Attempt to jump.
if (this.tryToJump) //Jumping while crouching would be a bit silly.
{
//In the following, note that the jumping velocity changes are computed such that the separating velocity is specifically achieved,
//rather than just adding some speed along an arbitrary direction. This avoids some cases where the character could otherwise increase
//the jump speed, which may not be desired.
if (this.SupportFinder.HasTraction)
{
//The character has traction, so jump straight up.
float currentDownVelocity;
Vector3.Dot(ref this.down, ref relativeVelocity, out currentDownVelocity);
//Target velocity is JumpSpeed.
float velocityChange = Math.Max(this.jumpSpeed + currentDownVelocity, 0);
this.ApplyJumpVelocity(this.down * -velocityChange, ref relativeVelocity);
//Prevent any old contacts from hanging around and coming back with a negative depth.
foreach (var pair in this.Body.CollisionInformation.Pairs)
{
pair.ClearContacts();
}
this.SupportFinder.ClearSupportData();
this.supportData = new SupportData();
}
else
{
Utilities.Logger.Error("Support Does not have traction");
}
}
this.tryToJump = false;
}
finally
{
this.UnlockCharacterPairs();
}
//Vertical support data is different because it has the capacity to stop the character from moving unless
//contacts are pruned appropriately.
Vector3 movement3D;
this.HorizontalMotionConstraint.GetMovementDirectionIn3D(out movement3D);
this.HorizontalMotionConstraint.SupportData = this.supportData;
SupportData verticalSupportData;
this.SupportFinder.GetTractionInDirection(ref movement3D, out verticalSupportData);
this.VerticalMotionConstraint.SupportData = verticalSupportData;
}
public bool GetTractionInDirection(ref Vector3 movementDirection, out SupportData supportData)
{
if (this.HasTraction)
{
int greatestIndex = -1;
float greatestDot = -float.MaxValue;
for (int i = 0; i < this.supports.Count; i++)
{
if (this.supports.Elements[i].HasTraction)
{
float dot;
Vector3.Dot(ref movementDirection, ref this.supports.Elements[i].Contact.Normal, out dot);
if (dot > greatestDot)
{
greatestDot = dot;
greatestIndex = i;
}
}
}
if (greatestIndex != -1)
{
supportData.Position = this.supports.Elements[greatestIndex].Contact.Position;
supportData.Normal = this.supports.Elements[greatestIndex].Contact.Normal;
supportData.SupportObject = this.supports.Elements[greatestIndex].Support;
supportData.HasTraction = true;
float depth = -float.MaxValue;
for (int i = 0; i < this.supports.Count; i++)
{
if (this.supports.Elements[i].HasTraction)
{
float dot;
Vector3.Dot(ref this.supports.Elements[i].Contact.Normal, ref supportData.Normal, out dot);
dot = dot * this.supports.Elements[i].Contact.PenetrationDepth;
if (dot > depth)
{
depth = dot;
}
}
}
supportData.Depth = depth;
return(true);
}
//Okay, try the ray cast result then.
if (this.SupportRayData != null && this.SupportRayData.Value.HasTraction)
{
supportData.Position = this.SupportRayData.Value.HitData.Location;
supportData.Normal = this.SupportRayData.Value.HitData.Normal;
supportData.Depth = Vector3.Dot(this.character.Down, this.SupportRayData.Value.HitData.Normal) * (this.bottomHeight - this.SupportRayData.Value.HitData.T);
supportData.SupportObject = this.SupportRayData.Value.HitObject;
supportData.HasTraction = true;
return(true);
}
//Well that's strange!
supportData = new SupportData();
return(false);
}
else
{
supportData = new SupportData();
return(false);
}
}
