/// <summary>
/// Gets the point on the sketch plane that is intersected by a given ray
/// </summary>
/// <param name="sketchPlane">The sketch plane</param>
/// <param name="lineRange">The ray information</param>
/// <returns>The point on the plane of <paramref name="sketchPlane"/> that intersects the ray given by <paramref name="lineRange"/>, or <c>null</c>
/// if no such point exists.</returns>
public static Point3D?PointFromRay(this SketchPlane sketchPlane, LineRange lineRange)
{
Contract.Requires(sketchPlane != null);
var plane = Plane3D.FromPointAndNormal(sketchPlane.Center, sketchPlane.Normal);
var t = plane.IntersectLine(lineRange.Point1, lineRange.Point2);
if (double.IsNaN(t))
{
return(null);
}
else
{
return(MathUtils3D.Lerp(lineRange.Point1, lineRange.Point2, t));
}
}
private NewConeViewModel.DragStartProximities GetDragStartProximity(LineRange startRay)
{
NewConeViewModel.DragStartProximities result = default(NewConeViewModel.DragStartProximities);
bool success = false;
var htParams = new RayHitTestParameters(startRay.Point1, startRay.Point2 - startRay.Point1);
var topNode = this.VisualPathUp().TakeWhile(x => x is Visual3D).OfType <Visual3D>().Last();
VisualTreeHelper.HitTest(
topNode,
null,
htResult =>
{
if (htResult.VisualHit.VisualPathUp().Contains(cylinder))
{
var htResult3d = htResult as RayMeshGeometry3DHitTestResult;
var topPlane = Plane3D.FromPointAndNormal(viewModel.Center + 0.5 * viewModel.Length * viewModel.Axis, viewModel.Axis);
var botPlane = Plane3D.FromPointAndNormal(viewModel.Center - 0.5 * viewModel.Length * viewModel.Axis, viewModel.Axis);
var topDist = topPlane.DistanceFromPoint(htResult3d.PointHit);
var botDist = botPlane.DistanceFromPoint(htResult3d.PointHit);
if (topDist < botDist)
{
result = NewConeViewModel.DragStartProximities.Top;
}
else
{
result = NewConeViewModel.DragStartProximities.Bottom;
}
success = true;
return(HitTestResultBehavior.Stop);
}
else
{
return(HitTestResultBehavior.Continue);
}
},
htParams);
Debug.Assert(success == true);
return(result);
}
