private HitTestResultBehavior HitTestCallback(HitTestResult result)
{
RayMeshGeometry3DHitTestResult rayHit = result as RayMeshGeometry3DHitTestResult;
ProjectionCamera camera = _viewport3D.Viewport.Camera as ProjectionCamera;
HitTestResultBehavior result2;
if (rayHit != null && rayHit.ModelHit != null)
{
Model3D model = rayHit.ModelHit;
Visual3D visual3D = rayHit.VisualHit;
if (visual3D != null)
{
if (string.Compare(Convert.ToString(visual3D.GetValue(FrameworkElement.NameProperty)), "CurveVisual") != 0)
{
result2 = HitTestResultBehavior.Continue;
return(result2);
}
}
MeshGeometry3D mesh = rayHit.MeshHit;
if (mesh != null)
{
Point3D p = mesh.Positions[rayHit.VertexIndex1];
Point3D p2 = mesh.Positions[rayHit.VertexIndex2];
Point3D p3 = mesh.Positions[rayHit.VertexIndex3];
double x = p.X * rayHit.VertexWeight1 + p2.X * rayHit.VertexWeight2 + p3.X * rayHit.VertexWeight3;
double y = p.Y * rayHit.VertexWeight1 + p2.Y * rayHit.VertexWeight2 + p3.Y * rayHit.VertexWeight3;
double z = p.Z * rayHit.VertexWeight1 + p2.Z * rayHit.VertexWeight2 + p3.Z * rayHit.VertexWeight3;
// point in local coordinates
Point3D localPoint = new Point3D(x, y, z);
Point3D p4 = localPoint;
// transform to global coordinates
// first transform the Model3D hierarchy
GeneralTransform3D t2 = Viewport3DHelper.GetTransform(rayHit.VisualHit, rayHit.ModelHit);
if (t2 != null)
{
p4 = t2.Transform(p4);
}
// then transform the Visual3D hierarchy up to the Viewport3D ancestor
GeneralTransform3D t3 = Viewport3DHelper.GetTransform(_viewport3D.Viewport, rayHit.VisualHit);
if (t3 != null)
{
p4 = t3.Transform(p4);
}
double distance = (camera.Position - p4).LengthSquared;
if (distance < _minimumDistance)
{
_minimumDistance = distance;
_nearestPt = localPoint;
_nearestNormal = Vector3D.CrossProduct(p2 - p, p3 - p);
_rayhit = rayHit;
}
}
}
result2 = HitTestResultBehavior.Continue;
return(result2);
}
/// <summary>
/// Intersects the specified source mesh geometry with the specified plane.
/// </summary>
/// <param name="source">The source.</param>
/// <param name="inverseTransform">The inverse transform of the source.</param>
/// <param name="plane">The plane.</param>
/// <param name="complement">Cut with the complement set if set to <c>true</c>.</param>
/// <returns>The intersected geometry.</returns>
private MeshGeometry3D Intersect(MeshGeometry3D source, GeneralTransform3D inverseTransform, Plane3D plane, bool complement)
{
var p = inverseTransform.Transform(plane.Position);
var p2 = inverseTransform.Transform(plane.Position + plane.Normal);
var n = p2 - p;
if (complement)
{
n *= -1;
}
return(MeshGeometryHelper.Cut(source, p, n));
}
/// <summary>
/// Update the transformation on the controlled object as the dragged-mouse moves. (Ignore if the motion's not part of a drag).
///
/// </summary>
public void mouseMove(System.Windows.Input.MouseEventArgs e)
{
// if not in drag, ignore
// if in drag,
// note that current point may not lie on sphere!
// compute rotation taking start-point to current point
// concatenate that with initial transform
if (_inDrag)
{
Debug.Print("In drag!");
Point3D currPoint = spherePointFromMousePosition(e.GetPosition(_viewport3D));
Point3D origin = new Point3D(0, 0, 0);
GeneralTransform3D tt = _initialTransform.Inverse;
Vector3D vec1 = tt.Transform(_startPoint) - tt.Transform(origin);
Vector3D vec2 = tt.Transform(currPoint) - tt.Transform(origin);
Debug.Print(" vec1: " + vec1.ToString());
Debug.Print(" vec2: " + vec2.ToString());
vec1.Normalize();
vec2.Normalize();
// Now build an arcball interaction to take vec1 to vec2 and past it (i.e., double the rotation):
double angle = 2 * Math.Acos(Vector3D.DotProduct(vec1, vec2));
Vector3D axis = Vector3D.CrossProduct(vec1, vec2);
RotateTransform3D rotateTransform = new RotateTransform3D();
rotateTransform.Rotation = new AxisAngleRotation3D(axis, 180 * angle / Math.PI);
Debug.Print("axis: " + axis.ToString());
Debug.Print("angle: " + angle.ToString());
Transform3DGroup tg = new Transform3DGroup();
tg.Children.Add(rotateTransform);
tg.Children.Add(_initialTransform);
_controlled.Transform = tg;
}
}
