add

var Command = &command.Command{
	Usage: `add [--from <age>] [--to <age>] [--at <age>]
	[-f|--format <format>] --in <model-file> --val <value>
	<time-pix-file>`,
	Short: "add pixels to a time pixelation",
	Long: `
Command add reads pixels from a reconstruction model at a given age, and them
to a time pixelation.

The flag --in is required and is used to provide the name of the input file.
By default, a tectonic reconstruction model will be used, other kind of files
can be used, defined by the flag --format, or -f. Valid formats are:

	mask	an image used as mask
	model	default value, a tectonic reconstruction model
	pix	a pixelated plates file

In the case of a mask image a pixelated plates file, a single time (defined
with the flag --at in million years) must be defined. For the mask image also
it requires that the base time pixelation exists. The image mask should be in
plate carrée projection (also known as equirectangular projection), and only
pixels in white will be set with the indicated value.

The flag --val is required and sets the value used for the pixels to be
assigned. If the pixel has a value already, the largest value will be stored.

The argument of the command is the file that contains the time pixelation. If
the files does not exist, it will create a new file, if it exists, pixels will
be added to that file.

By default, all time stages of the source model (as defined by --in) will be
used. With the flags --from and --to, it will use only the stages inside of the
indicated ages (in million years). Another possibility is using the flag --at
to set a particular time stage.
	`,
	SetFlags: setFlags,
	Run:      run,
}