how to make region if the 3D points are non coplanar using vba

Hi All

I am working on auto cad back end vba how to make a region if the 3D points are non coplanar can any one help it is urgent

Thanka in Advance

The Region is a planar entity, though that plane can have any orientation.

Can you post an example file showing what you have to work with and what you would like to have as a result?

The Region is a planar entity, though that plane can have any orientation.

 

Can you post an example file showing what you have to work with and what you would like to have as a result?

for example

the points are

' Define the four coordinates of the face

point1(0) = 0#: point1(1) = 0#: point1(2) = 0#

point2(0) = 5#: point2(1) = 0#: point2(2) = 0#

point3(0) = 5#: point3(1) = 5#: point3(2) = 20#

point4(0) = 0#: point4(1) = 5#: point4(2) = 20#

then by using this points how to make a region using vba

This would be the format for those specific points. Conceivably, you will have to modify the process a bit to accommodate arbitrary points. You may also want to delete the temporary lines.

Sub RegionFromPts()

   
   Dim curves(0 To 3) As AcadEntity
   Dim point1(0 To 2) As Double
   Dim point2(0 To 2) As Double
   Dim point3(0 To 2) As Double
   Dim point4(0 To 2) As Double
   
     point1(0) = 0#: point1(1) = 0#: point1(2) = 0#
     point2(0) = 5#: point2(1) = 0#: point2(2) = 0#
     point3(0) = 5#: point3(1) = 5#: point3(2) = 20#
     point4(0) = 0#: point4(1) = 5#: point4(2) = 20#



   Set curves(0) = ThisDrawing.ModelSpace.AddLine(point1, point2)
   Set curves(1) = ThisDrawing.ModelSpace.AddLine(point2, point3)
   Set curves(2) = ThisDrawing.ModelSpace.AddLine(point3, point4)
   Set curves(3) = ThisDrawing.ModelSpace.AddLine(point4, point1)
   ' Create the region
   Dim regionObj As Variant
   regionObj = ThisDrawing.ModelSpace.AddRegion(curves)
   ZoomAll
   
End Sub

This would be the format for those specific points. Conceivably, you will have to modify the process a bit to accommodate arbitrary points. You may also want to delete the temporary lines.

 

Sub RegionFromPts()


   Dim curves(0 To 3) As AcadEntity
   Dim point1(0 To 2) As Double
   Dim point2(0 To 2) As Double
   Dim point3(0 To 2) As Double
   Dim point4(0 To 2) As Double

     point1(0) = 0#: point1(1) = 0#: point1(2) = 0#
     point2(0) = 5#: point2(1) = 0#: point2(2) = 10#
     point3(0) = 5#: point3(1) = 5#: point3(2) = 20#
     point4(0) = 0#: point4(1) = 5#: point4(2) = 30#



   Set curves(0) = ThisDrawing.ModelSpace.AddLine(point1, point2)
   Set curves(1) = ThisDrawing.ModelSpace.AddLine(point2, point3)
   Set curves(2) = ThisDrawing.ModelSpace.AddLine(point3, point4)
   Set curves(3) = ThisDrawing.ModelSpace.AddLine(point4, point1)
   ' Create the region
   Dim regionObj As Variant
   regionObj = ThisDrawing.ModelSpace.AddRegion(curves)
   ZoomAll

End Sub

ya it works fine

but if i give z values like above 0 ,10, 20, 30 then it is not working

All four points have to be on the same plane. I’m not sure what tolerance AutoCAD uses for the AddRegion method, but I imagine it is pretty tight (1.0000E-06 perhaps).

In lieu of a separate test for planarity, the fact that a region can not be made may be a good indication that the points are not planar.

Accommodating non planar points may require the use of 3D Polylines, or broken down to two triangular Regions.