The order in which Unity renders objects is based on two things: which render queue the object is in, and how Unity sorts objects within that render queue.
Unity sorts objects into groups called render queues. Unity renders the contents of one render queue, and then renders the contents of another render queue, and so on.
Unity has the following named render queues, which it renders in the following order:
| Name | Index | Description |
|---|---|---|
| Background | 1000 | Use this queue for anything that should be drawn in the background of your Scene. |
| Geometry | 2000 | Use this queue for opaque geometry. This is the default queue. |
| AlphaTest | 2450 | Use this queue for alpha tested geometry. This is after the Geometry queue because it’s more efficient to render alpha-tested objects after all solid ones are drawn. |
| Transparent | 3000 | Use this queue for anything alpha-blended (shaders that don’t write to the depth buffer). Examples include glass, or particle effects. |
| Overlay | 4000 | Use this queue for effects that are rendered on top of everything else, such as lens flares. |
Note that Skybox materials are a special case. Unity draws Skybox materials after all opaque geometry (after queue index 2500), but before all transparent geometry (before queue index 2501).
Within each render queue, Unity sorts and draws objects based on their distance from the camera. The sorting behavior depends on the index of the render queue:
How you change the sorting behavior within a render queue depends on the index of the render queue: