Define one or more macros for configuring the output layout

[sdilts]

There should be a way to set the configuration for each output such as scale factor, resolution, and layout using one or more declarative-style macros.

Layout positioning is probably going to be the most complex problem, as screen mirroring and other similar tasks can become fairly complex. One possibility is to define the layout as a series of regions, called heads. To get screen mirroring, you would assign two or more outputs to a head.