Re: [Super-tux-devel] Stalactite bad guy [patch]

[Ricardo C. <ri...@ae...>]

Em Quinta, 11 de Mar=E7o de 2004 11:05, o Bill Kendrick escreveu:
> On Thu, Mar 11, 2004 at 10:31:16AM +0000, Ricardo Cruz wrote:
>
> > > If we were being REALLY fancy, we could hand-code a blur routine that
> > > would actually give more of a glass effect.  But, since the graphics
> > > will be relatively small, blurring is relatively expensive, and it wi=
ll
> > > eventually all be moving so fast, I don't think it's worth it...
> >
> >  Not sure what you meant, but SuperTux has OpenGL support...
>
> As an option, I hope. ;^)  I reinstalled my Debian system recently and
> only have software GL support right now, for example. ;^)  It =3D=3D SLOW!
>

 OpenGL can be used by passing the --opengl / -gl argument.
 The decision was that, in the (far) future, if there are some things that=
=20
need to be done and cannot be implemented in SDL (for performance reasons)=
=20
and that affect the gameplay, SDL will be dropped, in favor of OpenGL.

> The gist of the idea is that instead of simply being see-through, or
> tinting the background, the ice could actually affect the clarity of
> the background behind it.
>
> I suppose one way to do it would be to:
>
>   1. Do a general blur of the area the stalactite takes (using a
>      mask to determine which pixels we should blur, so that we don't
>      waste time doing the full rectangular area around the object).
>

> ...look at the pixels in the background (before drawing any part of the
> stalactite) and combine them to blur it.  E.g., if the background looked
> like this:
>

>
> Mix the current background, with this alpha-masked blurred version and
> NOW, we have a cool "invisible Predator" style effect!
>

 SuperTux supports Alpha blending, so couldn't that be made by setting up s=
ome=20
pixels, in the stalactite image, to a value from 0-255 ?

(a part; stalactite normal image, can be animated!)

Ricardo Cruz

=2D-=20
Many of the convicted thieves Parker has met began their
life of crime after taking college Computer Science courses.
		-- Roger Rapoport, "Programs for Plunder", Omni, March 1981