/// <summary>
/// Perform one solver iteration. Returns true if converged.
/// </summary>
/// <param name="baumgarte">The baumgarte value.</param>
/// <returns></returns>
public bool Solve(float baumgarte)
{
float minSeparation = 0.0f;
for (int i = 0; i < _count; ++i)
{
TOIConstraint c = _constraints[i];
Body bodyA = c.BodyA;
Body bodyB = c.BodyB;
float massA = bodyA.Mass;
float massB = bodyB.Mass;
// Only the TOI body should move.
if (bodyA == _toiBody)
{
massB = 0.0f;
}
else
{
massA = 0.0f;
}
float invMassA = massA * bodyA.InvMass;
float invIA = massA * bodyA.InvI;
float invMassB = massB * bodyB.InvMass;
float invIB = massB * bodyB.InvI;
// Solve normal constraints
for (int j = 0; j < c.PointCount; ++j)
{
TOISolverManifold psm = new TOISolverManifold(ref c, j);
Vector2 normal = psm.Normal;
Vector2 point = psm.Point;
float separation = psm.Separation;
Vector2 rA = point - bodyA.Sweep.c;
Vector2 rB = point - bodyB.Sweep.c;
// Track max constraint error.
minSeparation = Math.Min(minSeparation, separation);
// Prevent large corrections and allow slop.
float C = MathUtils.Clamp(baumgarte * (separation + Settings.LinearSlop),
-Settings.MaxLinearCorrection, 0.0f);
// Compute the effective mass.
float rnA = MathUtils.Cross(rA, normal);
float rnB = MathUtils.Cross(rB, normal);
float K = invMassA + invMassB + invIA * rnA * rnA + invIB * rnB * rnB;
// Compute normal impulse
float impulse = K > 0.0f ? -C / K : 0.0f;
Vector2 P = impulse * normal;
bodyA.Sweep.c -= invMassA * P;
bodyA.Sweep.a -= invIA * MathUtils.Cross(rA, P);
bodyA.SynchronizeTransform();
bodyB.Sweep.c += invMassB * P;
bodyB.Sweep.a += invIB * MathUtils.Cross(rB, P);
bodyB.SynchronizeTransform();
}
}
// We can't expect minSpeparation >= -b2_linearSlop because we don't
// push the separation above -b2_linearSlop.
return(minSeparation >= -1.5f * Settings.LinearSlop);
}
/// <summary>
/// Perform one solver iteration. Returns true if converged.
/// </summary>
/// <param name="baumgarte">The baumgarte value.</param>
/// <returns></returns>
public bool Solve(float baumgarte)
{
float minSeparation = 0.0f;
for (int i = 0; i < _count; ++i)
{
TOIConstraint c = _constraints[i];
Body bodyA = c.BodyA;
Body bodyB = c.BodyB;
float massA = bodyA.Mass;
float massB = bodyB.Mass;
// Only the TOI body should move.
if (bodyA == _toiBody)
{
massB = 0.0f;
}
else
{
massA = 0.0f;
}
float invMassA = massA * bodyA.InvMass;
float invIA = massA * bodyA.InvI;
float invMassB = massB * bodyB.InvMass;
float invIB = massB * bodyB.InvI;
// Solve normal constraints
for (int j = 0; j < c.PointCount; ++j)
{
TOISolverManifold psm = new TOISolverManifold(ref c, j);
Vector2 normal = psm.Normal;
Vector2 point = psm.Point;
float separation = psm.Separation;
Vector2 rA = point - bodyA.Sweep.c;
Vector2 rB = point - bodyB.Sweep.c;
// Track max constraint error.
minSeparation = Math.Min(minSeparation, separation);
// Prevent large corrections and allow slop.
float C = MathUtils.Clamp(baumgarte * (separation + Settings.LinearSlop),
-Settings.MaxLinearCorrection, 0.0f);
// Compute the effective mass.
float rnA = MathUtils.Cross(rA, normal);
float rnB = MathUtils.Cross(rB, normal);
float K = invMassA + invMassB + invIA * rnA * rnA + invIB * rnB * rnB;
// Compute normal impulse
float impulse = K > 0.0f ? -C / K : 0.0f;
Vector2 P = impulse * normal;
bodyA.Sweep.c -= invMassA * P;
bodyA.Sweep.a -= invIA * MathUtils.Cross(rA, P);
bodyA.SynchronizeTransform();
bodyB.Sweep.c += invMassB * P;
bodyB.Sweep.a += invIB * MathUtils.Cross(rB, P);
bodyB.SynchronizeTransform();
}
}
// We can't expect minSpeparation >= -b2_linearSlop because we don't
// push the separation above -b2_linearSlop.
return minSeparation >= -1.5f * Settings.LinearSlop;
}