[Freeciv-Dev] Re: next beta

[Vasco Alexandre Da Silva Costa <vasc@xxxxxxxxxxxxxx>]

On Wed, 8 Dec 2004, Andreas Røsdal wrote:

> On Wed, 8 Dec 2004, Vasco Alexandre Da Silva Costa wrote:
> > > Maybe PR#8818 can be looked at again?
> > >
> > > To summarize it: change the fog of war to darken the whole tile,
> > > instead of making every other tile black. This causes flickering when
> > > sliding the map on an LCD montor.
> > >
> > > Take a look at this screenshot of Civ3 fog of war, for an example:
> > > http://img.gamershell.com/imagefolio/gallery/Strategy/Civilization_3/tanks.jpg
> >
> > For that you need alpha blending. The standard X11 API does not support
> > alpha blending (Win32 GDI on Windows 2000 does however). A solution would
> > be for someone to make an OpenGL port of the map drawing code. I tried,
> > but my code was too slow.
>
> I think that alpha blending in the GTK 2.x client should be possible.
> The GdkPixbuf function gdk_pixbuf_render_to_drawable_alpha() allows you
> to set an alpha threshold for the pixbuf you want to render. There is also
> a lot of other rendering functions which take alpha threshold values. So,
> can this be used to add alpha blending to the GTK 2.x client?  Even the
> examples which come with the GTK distribution have alpha blending.
> (gtk-pixbuf example).

Please no. GdkPixbuf is braindamaged and slow.

> A OpenGL client, or a way to do alpha-blending in the common code would be
> even better.

Yes.

> I don't know how the standard X11 API is used in the clients. Why would
> you want to use it for alpha blending anyway?

If it did have alpha blending, it could be hardware accelerated and we
wouldn't need to implement it ourselves.

---
Vasco Alexandre da Silva Costa @ Instituto Superior Tecnico, Lisboa