On Sun, 03 Aug 2008 14:23:27 -0700, David O'Toole <[EMAIL PROTECTED]> wrote:

> I am using #'lispbuilder-sdl:draw-surface-at-* to copy 16x16 PNG tiles
> to an offscreen surface (it's a tile-based roguelike game), then copying
> the whole composed image to the screen. I am loading the pngs with
> #'lispbuilder-sdl-image:load-image. In the old version of the engine,
> the transparent parts of the PNGs (i.e. the outline around the object)
> was not drawn, and everything looked proper. But since rewriting the
> engine the transparency no longer works, and i get ugly black borders
> around all my objects instead of seeing through to the previously drawn
> tile at that location.

lispbuilder-sdl used to always create a surface with a surface alpha  
component. I had to change this behaviour as it made a number of surface  
combinations impossible.

Try creating your surfaces with :SURFACE-ALPHA T, or :CHANNEL-ALPHA T.

:SURFACE-ALPHA sets SDL_SRC_ALPHA
:CHANNEL-ALPHA sets the amask to #xff000000

- Luke
_______________________________________________
application-builder mailing list
[email protected]
http://www.lispniks.com/mailman/listinfo/application-builder

Reply via email to