[GRASS5] rgb color support in ps.map ?

[Glynn Clements]

Michael Barton wrote:

> I'm sure that the updates discussed will be very helpful to many.
> 
> I'd like to list a request in a little different direction however, that I
> think would help even more people.
> 
> Is there any way to create a postscript output driver for a monitor window?

It wouldn't provide any benefit over using the PNG driver and
converting the result to PostScript. Otherise I would have written it
already.

The problem is that the raster graphics API is too oriented toward
screen display (e.g. operating in integer pixel coordinates, requiring
rasters to be scaled client-side etc).

Also, some clients rely upon low-level details of rendering operations
(e.g. assuming that drawing lines will set certain pixels, e.g. using
G_plot_polygon() with R_line_abs() to fill a polygon by drawing
horizontal lines).

A display architecture which did a half-way decent job of generating
PostScript would need to operate in abstract coordinates, with no
pixel-level guarantees about drawing operations and a scaled raster
primitive.

> Sending a monitor window (at whatever its current resolution is) to a
> postscript file, and then to a printer, would be very useful. This could
> work like d.png. But even doing it as graphic output (rather than the nicer
> ps.map output) would be a big help to many.

PNG driver + pnmtops.

You'll get jagged lines, but that's a problem of the display
architecture which can't be fixed in an individual driver.

-- 
Glynn Clements <glynn at gclements.plus.com>