public void SliceShapePostStep(cpSpace space, cpShape shape, SliceContext context)
{
cpVect a = context.a;
cpVect b = context.b;
// Clipping plane normal and distance.
cpVect n = cpVect.cpvnormalize(cpVect.cpvperp(cpVect.cpvsub(b, a)));
float dist = cpVect.cpvdot(a, n);
ClipPoly(space, shape, n, dist);
ClipPoly(space, shape, cpVect.cpvneg(n), -dist);
cpBody body = shape.GetBody();
space.RemoveShape(shape);
space.RemoveBody(body);
}
private void SliceObject(Vect from, Vect to)
{
var context = new SliceContext {
A = from,
B = to
};
SegmentQueryInfo[] infos = space.SegmentQuery(sliceStart, context.B, 0.0, ChipmunkDemoGame.GrabbableFilter).ToArray();
if (infos.Length == 0)
{
return;
}
foreach (SegmentQueryInfo info in infos)
{
SliceQuery(info.Shape, info.Point, info.Normal, info.Alpha, context);
}
}
public void SliceQuery(cpShape shape, float t, cpVect n, SliceContext context)
{
cpVect a = context.a;
cpVect b = context.b;
// Check that the slice was complete by checking that the endpoints aren't in the sliced shape.
cpPointQueryInfo inf1 = null;
cpPointQueryInfo inf2 = null;
if (shape.PointQuery(a, ref inf1) > 0 && shape.PointQuery(b, ref inf2) > 0)
{
// Can't modify the space during a query.
// Must make a post-step callback to do the actual slicing.
context.space.AddPostStepCallback(
(s, o1, o2) => SliceShapePostStep(s, (cpShape)o1, (SliceContext)o2),
shape, context);
}
}
private void SliceQuery(Shape shape, Vect point, Vect normal, double alpha, SliceContext context)
{
Vect a = context.A;
Vect b = context.B;
// Check that the slice was complete by checking that the endpoints aren't in the sliced shape.
PointQueryInfo infoA = shape.PointQuery(a);
if (infoA == null || infoA.Distance <= 0.0)
{
return;
}
PointQueryInfo infoB = shape.PointQuery(b);
if (infoB == null || infoB.Distance <= 0.0)
{
return;
}
// Can't modify the space during a query.
// Must make a post-step callback to do the actual slicing.
space.AddPostStepCallback(SliceShapePostStep, shape, context);
}
public override void Update(float dt)
{
base.Update(dt);
space.Step(dt);
bool lastClickState = false;
sliceStart = cpVect.Zero;
// Annoying state tracking code that you wouldn't need
// in a real event driven system.
if (CCMouse.Instance.rightclick != lastClickState)
{
if (CCMouse.Instance.rightclick)
{
// MouseDown
sliceStart = CCMouse.Instance.Position;
}
else
{
// MouseUp
SliceContext context = new SliceContext(sliceStart, CCMouse.Instance.Position, space);
space.SegmentQuery(sliceStart,
CCMouse.Instance.Position, 0, GRAB_FILTER, (shape, v1, v2, d, o) =>
SliceQuery(shape, d, v1, (SliceContext)o),
context);
}
lastClickState = CCMouse.Instance.rightclick;
}
write = CCMouse.Instance.rightclick;
}
public override object VisitSlice([NotNull] SliceContext context)
{
return((string)Visit(context.GetChild(0)));
}
