Checking for shape intersection

I've tried somthing like:

Shape1.GetPosition x,y
Shape2.IsOnShape (x,y)

but it's too slow. Now I'm using:

Set tempShape=shape1.Intersect(shape2)
tempShape.Delete

which looks clumsy but (Surprisingly!)is not slower then the first and is much more reliable.Can you give me any tips for improving performance?And is there any real documentation about CorelDraw12 object model ?
Thank you.

[shelbym]

I find the VBA help file to be the best resource, it includes examples and is pretty easy to follow here is the page on Intersect Shape.Intersect

Shape.Intersect

Function Intersect(ByVal TargetShape As Shape, [ByVal LeaveSource As Boolean = True], [ByVal LeaveTarget As Boolean = True]) As Shape

Description

The Intersect method creates an object which is an intersection of two shapes.
 
TargetShape
 Specifies the object that intersects with the shape object [in]
 
LeaveSource
 Determines whether to keep the shape object after the intersection is complete [in]
Optional
Default value = True
 
LeaveTarget
 Determines whether to keep the target object after the intersection is complete [in]
Optional
Default value = True 

Example

The following example creates a color diagram for the additive color model (RGB). Three circles are filled, each with red, green, and blue. At the intersections of the circles, the resulting color blend fills the areas: white in the middle, while cyan, magenta, and yellow fill the areas between each pair of circles.

Sub Test()

 Dim s(0 To 2) As Shape
 Dim si(0 To 2) As Shape
 Dim sm As Shape
 Dim x As Double, y As Double
 Dim i As Long, n As Long
 Dim r As Long, g As Long, b As Long
 Dim c1 As Color, c2 As Color

 For i = 0 To 2

  x = ActivePage.SizeWidth / 2 + 1 * Cos(i * 2.09439507)
  y = ActivePage.SizeHeight / 2 + 1 * Sin(i * 2.09439507)
  Set s(i) = ActiveLayer.CreateEllipse2(x, y, 1.5)
  r = -255 * (i = 0)
  g = -255 * (i = 1)
  b = -255 * (i = 2)
  s(i).Fill.UniformColor.RGBAssign r, g, b

 Next i

 For i = 0 To 2

  n = (i + 1) Mod 3
  Set si(i) = s(i).Intersect(s(n))
  Set c1 = s(i).Fill.UniformColor
  Set c2 = s(n).Fill.UniformColor
  r = c1.RGBRed + c2.RGBRed
  g = c1.RGBGreen + c2.RGBGreen
  b = c1.RGBBlue + c2.RGBBlue
  si(i).Fill.UniformColor.RGBAssign r, g, b

 Next i

 Set sm = si(1).Intersect(si(2))
 sm.Fill.UniformColor.RGBAssign 255, 255, 255

End Sub

[shelbym]

Here is the Shape.IsOnShape Example from the help file:

Sub Test()

 Dim s As Shape
 Dim x As Double, y As Double

 While ActiveDocument.GetUserClick(x, y, 0, 100, False, cdrCursorPickOvertarget) = 0

  For Each s In ActivePage.Shapes
   Select Case s.IsOnShape(x, y)
    Case cdrOnMarginOfShape
     If s.Outline.Type = cdrOutline Then
      s.Outline.Color.RGBAssign 255, 255, 0
      Exit For
     End If

    Case cdrInsideShape
     s.Fill.UniformColor.RGBAssign 255, 255, 0
     Exit For
   End Select
  Next s
 Wend

End Sub

[shelbym]

You might also try SubPath.GetIntesections, example follows:

The following example displays the number of times the two selected curves intersect, and marks each intersection point with a small circle.

Sub Test()

 Dim sr As ShapeRange
 Dim sp1 As SubPath, sp2 As SubPath
 Dim cps As CrossPoints, cp As CrossPoint
 Dim x As Double, y As Double, n As Long

 Set sr = ActiveSelectionRange

 If sr.Count <> 2 Then
  MsgBox "Please select two curves", vbCritical
  Exit Sub
 End If

 If sr(1).Type <> cdrCurveShape Or sr(2).Type <> cdrCurveShape Then
  MsgBox "One of the selected shapes is not a curve", vbCritical
  Exit Sub
 End If

 n = 0
 For Each sp1 In sr(1).Curve.Subpaths
  For Each sp2 In sr(2).Curve.Subpaths
   Set cps = sp1.GetIntersections(sp2)
   For Each cp In cps

   ActiveLayer.CreateEllipse2 cp.PositionX, cp.PositionY, 0.05
   Next cp
   n = n + cps.Count
  Next sp2
 Next sp1

 MsgBox n & " intersection point(s) found"
End Sub