Message-ID: From: Shawn Hargreaves To: djgpp AT delorie DOT com Subject: Re: Allegro: Translucency and Blending Date: Fri, 21 Jan 2000 15:38:18 -0000 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain; charset="iso-8859-1" Reply-To: djgpp AT delorie DOT com Night Walker writes: > I must draw a translucent 8bpp bitmap on a 15/16/24/32bpp screen. > Which functions I must call to create the trans table(s?)? You can't, because Allegro doesn't support mixing color depths like that. See "info allegro converting" for a full explanation, but in brief, only the blit() function has full support for mixing different color depths (it's the workhorse routine used to convert between formats), while a few other routines have support for specific useful and simple combinations, for example draw_sprite() is able to display 256 color source images on any format of destination. But in general, mixing formats doesn't work, and should be avoided. The easy approach is to convert all your images into the screen format while they are being loaded: Allegro makes this very easy if you use the set_color_conversion(), load_datafile(), and/or load_bitmap() calls. Shawn Hargreaves.