To draw custom areas of an application, our application will be interacting directly with the Nuklear draw command queue (the list of items to draw for rendering a frame of the user interface) so care is recommended. You can get access to nk.CommandBuffer, which is needed for each draw command by using the NkWindowGetCanvas() function. It's important that this is only called when a window is active (after NkBegin and before NkEnd). The positional values will need to be aware of other widgets and layouts loaded, which can get complicated very fast—it's easiest to draw using these commands only in an otherwise empty window so that you avoid drawing over other widgets.