1. CPQ
  2. 3D Scenes
  3. 3D Scene Mesh Features

Geometry Join Feature

Article last updated:

The Geometry Join Feature combines two separate meshes in a variety of ways.

This feature Allows for the creation of complex shapes and geometries by combining multiple meshes. Three join styles are available: cut, intersect, and union. In the example below see on the left, two meshes. To the right, three resulting joins: cut, intersect, and union.

 

Geometry Join Feature Properties

Visualizing this Feature

Example: using the “Geometry Join ” feature

Property Options

Name

Name the feature. Unique names for each feature is not required, but suggested.

Target Mesh

Clicking this button allows you to select the mesh to be combined with the parent mesh.

After selecting the target, the feature takes a moment to calculate. Then…

  • Logically, the target mesh still exists. It is still listed in the node explorer on the left, and any changes made to it will effect the parent mesh.

  • Visually the target mesh changes. The visible property is set to false, so it disappears from the scene.

Join Type

The Join Type Property defines how the meshes will interact with each other:

Cut - The portion of the parent mesh that intersects with the target mesh will be removed. The target mesh itself remains unchanged, but is marked invisible.

Union - The parent mesh gains the geometry of the target mesh. The target mesh itself remains unchanged, but is marked invisible.

Intersect - The portions of the Parent and Target meshes that don’t overlap will be removed, and only the overlapping portions remain to become the geometry of the parent mesh.

 

When this feature is selected in the feature stack, a visualization appears in the scene to help you manage it.

  • A yellow visualization appears: it shows the geometry of the target mesh.

  1. Meshes > Create Primitive > Create Box.

  2. Change box shape properties to height/width/depth of 1/2/1.

  3. Meshes > Create Primitive > Create Cylinder.

  4. Change cylinder properties Position x=-0.5, y=0.25

  5. Change cylinder shape properties Radius=.25, height 1.10.

  6. Select Cylinder, add feature: Linear Pattern.

  7. Pattern translation 1,0,0.

  8. Pattern count: 2.

  9. Select Box, add feature: Join Geometry.

  10. Target Mesh: Cylinder.

The target mesh’s visibility is set to false after being marked as the target mesh for any Geometry Join feature. This is so you can immediately see the results of your join without the target mesh getting in the way. The invisible target mesh is still driving the geometry of the join: you can move it, rotate it, etc. and immediately see the results of your changes in the other mesh with the feature applied.

For example, after following the steps above, select the now-invisible cylinder mesh by clicking its entry in the explorer tree. Move or rotate the cylinder, and you’ll see those changes applied across the linear pattern feature of the cylinder, and into the join geometry feature of the box. Delete the cylinder, and you’ll see the geometry of the box change.

Tips

  • Watch the order of features.
    If you are adding the Geometry Join feature to a mesh’s feature stack, and that feature stack already has a Move Vertices feature, we suggest the Geometry Join be moved later in the stack, below the Move Vertices feature. If placed before the move vertices feature, geometry join may add vertices to the object that make selecting vertices in the move vertices feature more difficult.

  • The union option is rarely used.
    Meshes already overlap when they are in the same location in the scene, so the appearance of a union happens simply by moving two meshes into close coordinates. In the screenshot of a cylinder and cube shown above, note how the union operation on the right looks almost identical to the two independent meshes on the left.

    Instead of applying a union, first try simply placing the two meshes into a group, and then treating the group as the object (move or rotate the group). You’ll find the simple geometry of two overlapping meshes renders faster than the more complex geometry resulting from one joined mesh.

  • Stack geometry join features for complex results.
    The join feature, like all features, can be used multiple times in the feature stack. In the image below, from left to right:

A red sphere with no features.

A red sphere with a geometry join feature: it is cut with a second glassy sphere to give a bowl shape.

That same mesh with a second geometry join feature: it is cut again with a glassy cylinder to give a complex saddle shape.

  

There’s more than one way to cut into a mesh.
Remember two techniques are available for showing the interior of a mesh: A slice plane, and a union/cut box. In the following water valve example, we cutaway the grey metal valve assembly to show the orange ball valve. The top assembly is union/cut with a box mesh, the bottom assembly is cut with a slice plane. Notice the difference:

  • On top, the assembly with a union/cut feature looks like solid silver metal. Union/cut completes the cut edges of the parent mesh (it merges geometry of the box and assembly).

  • On the bottom, the assembly with a slice plane feature looks like a hollow model. The slice plane adds no geometry to the cut plane of the assembly.

 

 

Was this article helpful?