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UE3 Home > Unreal Editor and Tools > Reference Tree Tool

Reference Tree Tool


The Reference Tree is a tool that allows you to list the reference chains for a specific asset. A reference chain is a list of references in which each object in the list references the objects below it in the list. The reference tree tool allows you to easily find how objects are being referenced. In the following image you can see that the root of the tree is a texture named T_Ivy_01_D. The root of the tree is always the object being examined. You can see that the texture is referenced by four actors via a material and a static mesh. In other words, the texture is used in a material instance constant which is the material on a static mesh used by the four actors.


The previous image is a simple example and the actual results can be much more complex depending on your levels. Here is an example of a more complex tree in which a texture has many different paths to actors.


Using the Reference Tree

To use the reference tree simply right click on object in the content browser and select the "Show Reference Tree" menu option.


The initial load of the reference tree dialog may take a few seconds depending on how complex your game is and how many objects you have. Internally the reference tree builds a graph of all objects in order to find a complete list of references. This takes some time.

Once the dialog is open searches for new assets is very fast. The dialog stays on top of the editor main frame and does not block other work. To start a new search once the dialog is already open, simply right click on any object in the content browser and choose "Show Reference Tree" or drag and drop an asset from the content browser into the reference tree dialog.


View Menu

  • Rebuild Tree: This regenerates the tree and examines all loaded objects. This may take some time but it is useful if you have changed references to the asset being examined.
  • Expand All: Expands all nodes in the tree.
  • Collapse All: Collapses all nodes in the tree.

Options Menu

  • Show Script References By default references to assets in script are not shown. To show them, you can check this option.

Context Menu

It is possible to right click items in the tree.

If you right click on an actor you will get this menu:

  • Select Actor: Selects and focuses in on the actor in the perspective viewport. Note: Double clicking on the actor in the reference tree will also do this.
  • View Properties: Views the property window for the actor.

If you right click on a browsable asset you get this menu:

  • Show in Content Browser: Syncs the content browser to the selected asset. Note: Double clicking on the asset in the reference tree will also do this.
  • Open Editor: Opens the editor specific to the asset you click on. For example using this on a skeletal mesh will show the AnimSet Viewer for the skeletal mesh.


  • The reference tree tool only shows browsable objects or actors.
  • Due to performance reasons with the tree, only the first 100 items in each leaf of the tree are shown. If there are more than 100 items a node will be added saying how much more there are.
  • The tool is a work in progress currently.