Maplands uses a depth buffer to render the world progressively
A depth buffer can be enabled for a layer. By specifying the depth of the current drawing operation, it can be drawn on top of previously drawn contents while preserving detail based on depth. This feature is used by Maplands to render block tiles of the world. Unlike layers, there are up to 65536 levels of depth here, but drawing a higher layer on a lower layer erases the lower layer's contents.
