The Extra Texture Render Element renders the entire scene project with one texture mapped onto all objects in the sceneproject. The texture applied to the scene project can be a bitmap or a procedural texture such as Dirt or Curvature.
A common use for the ExtraTex is to use Dirt as the texture, which creates an ambient occlusion element for use in the composite. In this way, ambient occlusion can be controlled separately during the compositing process.
While you can obtain a result similar to the ExtraTex render element by applying the same texture to all objects in the scene project and rendering as usual, such an approach requires additional time spent on reverting to actual materials, saving different versions of the sceneproject, etc. The ExtraTex render element provides you with a quick and easy way to render the scene project with a single texture without the extra work.
