Re: Any utility to adding grayscale/greyscale to terminal options

[sfeam <sf...@us...>]

On Saturday, 21 February 2015 02:05:38 AM Daniel J Sebald wrote:
> The other day I pointed out the behavior of the "monochrome" option that 
> the majority of terminals have in a bug report.  Ethan pointed out the 
> legacy nature of it and not knowing how to handle rgb objects under the 
> "mono" option.  Right now, it looks like most terminals treat "mono" as 
> being a binary color, or single pen color (black).
> 
> I'm wondering if it would make sense to add a third option here, 
> grayscale.  So most terminals would have:
> 
> {color | colour | grayscale | greyscale | monochrome}
> 
> Color is obvious, I guess.  Grayscale would map colors to grayscale. 

IMHO this is the job of the viewer/printer/image-editer rather
than gnuplot. 

> Monochrome would map colors and grayscale palette to either white or 
> black, say a formula for which white is the top "half" of the range and 
> black is the bottom half.  E.g.,
> 
> rgb 0xff9f00 -> gray 0x8a -> mono 0x1
> rgb 0xff6f00 -> gray 0x7a -> mono 0x0
> 
> It might be nice having the grayscale option.
> 
> The reason that grayscale and monochrome seem useful is that internally 
> the terminal may be able to do things to customize the output.  For 
> example, postscript might be able to reduce the size of the file if 
> grayscale is used as opposed to color.

The PostScript terminal already does this.  Palette colors are represented
by a single scalar value.  In "mono" mode this is executed as a greyscale
command, in "color" mode it is executed via a PostScript routine that 
reproduces the palette color mapping.

	Ethan