An opaque handle to a render target object.

Render targets are collections of images that can be rendered into. Each image in the collection is referred to as an "attachment". Some attachments have special meaning, for example the depth or the combined depth+stencil attachment, the contents of which are used in depth/stencil tests. A render target is not allowed to have multiple depth or depth+stencil attachments, however it is allowed to have multiple color attachments (up to a certain limit).