public static float FindMinSeparation(out int indexA, out int indexB, float t)
{
Transform xfA, xfB;
_sweepA.GetTransform(out xfA, t);
_sweepB.GetTransform(out xfB, t);
switch (_type)
{
case SeparationFunctionType.Points:
{
Vector2 axisA = MathUtils.MulT(ref xfA.q, _axis);
Vector2 axisB = MathUtils.MulT(ref xfB.q, -_axis);
indexA = _proxyA.GetSupport(axisA);
indexB = _proxyB.GetSupport(axisB);
Vector2 localPointA = _proxyA.Vertices[indexA];
Vector2 localPointB = _proxyB.Vertices[indexB];
Vector2 pointA = MathUtils.Mul(ref xfA, localPointA);
Vector2 pointB = MathUtils.Mul(ref xfB, localPointB);
float separation = Vector2.Dot(pointB - pointA, _axis);
return(separation);
}
case SeparationFunctionType.FaceA:
{
Vector2 normal = MathUtils.Mul(ref xfA.q, _axis);
Vector2 pointA = MathUtils.Mul(ref xfA, _localPoint);
Vector2 axisB = MathUtils.MulT(ref xfB.q, -normal);
indexA = -1;
indexB = _proxyB.GetSupport(axisB);
Vector2 localPointB = _proxyB.Vertices[indexB];
Vector2 pointB = MathUtils.Mul(ref xfB, localPointB);
float separation = Vector2.Dot(pointB - pointA, normal);
return(separation);
}
case SeparationFunctionType.FaceB:
{
Vector2 normal = MathUtils.Mul(ref xfB.q, _axis);
Vector2 pointB = MathUtils.Mul(ref xfB, _localPoint);
Vector2 axisA = MathUtils.MulT(ref xfA.q, -normal);
indexB = -1;
indexA = _proxyA.GetSupport(axisA);
Vector2 localPointA = _proxyA.Vertices[indexA];
Vector2 pointA = MathUtils.Mul(ref xfA, localPointA);
float separation = Vector2.Dot(pointA - pointB, normal);
return(separation);
}
default:
Debug.Assert(false);
indexA = -1;
indexB = -1;
return(0.0f);
}
}
