Re: Deprecated calls in libzvt

[Owen Taylor <otaylor redhat com>]

Joe Shaw <joe ximian com> writes:

> On Mon, 2002-02-04 at 11:41, Havoc Pennington wrote:
> > > It also uses GdkFont which is again deprecated. Should this be
> > > ported to use Pango?
> > 
> > No, Pango doesn't make sense for a terminal. If it's ported it should
> > be to Xlib (XFontStruct, XLoadFont(), etc.)
> 
> What makes Pango inherently inappropriate for a terminal?  I can see how
> a PangoLayout wouldn't work, but couldn't you implement a
> PangoTerminalLayout or something similar?  (Not that it isn't a lot of
> work, I am just curious.)

The basic problem is that handling of complex situations
(bidirectional text, ligatures, etc.) is quite different for text in
terminals and continuously flowed text. You can only do an
approximation of the right thing in a terminal. This is true not only
at the PangoLayout level, but at the level of language specific
handling.

The Motif complex-text handling only ever did this approximation in
any situation, so it was possible to use the same handling for Motif
entry widgets and for dtterm; however, Pango is really meant only for
continuous text layout. To make it possible to use Pango in a terminal
you'd have to extend the PangoEngineShape vtable to not only have
script_shape() but also to have some sort of terminal_shape() method.

Regards,
                                        Owen