Edit 3D Solids

Once you have created a solid, you can create more complex shapes by combining solids. You can join solids, subtract solids from each other, or find the common volume (overlapping portion) of solids. Use the Boolean or CheckInterference method to perform these combinations.

Solids are further modified by obtaining the 2D cross section of a solid or slicing a solid into two pieces. Use the SectionSolid method to find cross sections of solids, and the SliceSolid method for slicing a solid into two pieces.

Find the interference between two solids

This example creates a box and a cylinder in model space. It then finds the interference between the two solids and creates a new solid from that interference. For ease of viewing, the box is colored white, the cylinder is colored cyan, and the interference solid is colored red.

```Sub Ch8_FindInterferenceBetweenSolids()
```
```	' Define the box
```
```	Dim boxObj As Acad3DSolid
```
```	Dim length As Double
```
```	Dim width As Double
```
```	Dim height As Double
```
```	Dim center(0 To 2) As Double
```
```	center(0) = 5: center(1) = 5: center(2) = 0
```
```	length = 5
```
```	width = 7
```
```	height = 10
```

```	' Create the box object in model space
```
```	' and color it white
```
```	Set boxObj = ThisDrawing.ModelSpace. _
```
```				AddBox(center, length, width, height)
```
```	boxObj.Color = acWhite
```

```	' Define the cylinder
```
```	Dim cylinderObj As Acad3DSolid
```
```	Dim cylinderRadius As Double
```
```	Dim cylinderHeight As Double
```
```	center(0) = 0: center(1) = 0: center(2) = 0
```
```	cylinderRadius = 5
```
```	cylinderHeight = 20
```

```	' Create the Cylinder and
```
```	' color it cyan
```
```	Set cylinderObj = ThisDrawing.ModelSpace.AddCylinder _
```
```				 (center, cylinderRadius, cylinderHeight)
```
```	cylinderObj.Color = acCyan
```

```	' Find the interference between the two solids
```
```	' and create a new solid from it. Color the
```
```	' new solid red.
```
```	Dim solidObj As Acad3DSolid
```
```	Set solidObj = boxObj.CheckInterference(cylinderObj, True)
```
```	solidObj.Color = acRed
```
```	ZoomAll
```
```End Sub
```

Slice a solid into two solids

This example creates a box in model space. It then slices the box based on a plane defined by three points. The slice is returned as a 3DSolid.

```Sub Ch8_SliceABox()
```
```	' Create the box object
```
```	Dim boxObj As Acad3DSolid
```
```	Dim length As Double
```
```	Dim width As Double
```
```	Dim height As Double
```
```	Dim center(0 To 2) As Double
```
```	center(0) = 5#: center(1) = 5#: center(2) = 0
```
```	length = 5#: width = 7: height = 10#
```

```	' Create the box (3DSolid) object in model space
```
```	Set boxObj = ThisDrawing.ModelSpace. _
```
```				AddBox(center, length, width, height)
```
```	boxObj.Color = acWhite
```

```	' Define the section plane with three points
```
```	Dim slicePt1(0 To 2) As Double
```
```	Dim slicePt2(0 To 2) As Double
```
```	Dim slicePt3(0 To 2) As Double
```

```	slicePt1(0) = 1.5: slicePt1(1) = 7.5: slicePt1(2) = 0
```
```	slicePt2(0) = 1.5: slicePt2(1) = 7.5: slicePt2(2) = 10
```
```	slicePt3(0) = 8.5: slicePt3(1) = 2.5: slicePt3(2) = 10
```

```	' slice the box and color the new solid red
```
```	Dim sliceObj As Acad3DSolid
```
```	Set sliceObj = boxObj.SliceSolid _
```
```					(slicePt1, slicePt2, slicePt3, True)
```
```	sliceObj.Color = acRed
```
```	ZoomAll
```
```End Sub
```