Re: [Gnome-print] RGBA & DPI

[Lauris Kaplinski <lauris ariman ee>]

On Sat, 8 Apr 2000 clahey@helixcode.com wrote:

> 
> > > 2. Applications need to know preferred DPI values for printers to
> > > implement special (gradient, fractal) fill with optimal resolution. The
> > > RGBA rendering for PostScript should also use it.
> 
> Doesn't postscript support some of these operations?  Perhaps we should
> add them to the api with a implementation of rendering in the rgb like
> drivers?

It was about 5 years ago when I programmed in real PS language.
As much, as I remember - yes - PS allows to specify arbitrary fill
behaviour, but this is specified as cell-filling function in PS language.
So I am afraid, we cannot export this to gnome-print API easily.

Actually I've thought about a callback system, a la:

buf = xxx_print_prepare_buffer (gint width, gint height, gpointer data);
xxx_print_get_pixel (buf, gint x, gint y, gpointer data);
xxx_print_release_buffer (buf);

Use code can decide, if it allocates buffer & fills it once, or calculates
pixel value every time.

The fill can then be specified, as

gnome_print_eofill_full (pc, prepare_func, pixel_func, release_func, 
			 data);

Regards,
Lauris