Message-ID: <51CC8BA6EC01D1118E3200A024B9625B347983@mailhost.probe.co.uk> From: Shawn Hargreaves To: djgpp AT delorie DOT com Subject: Re: modex (?) Date: Tue, 9 Dec 1997 14:48:09 -0000 MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk Salvador Eduardo Tropea (SET writes: >> In an old pascal Xlib i've ported to djgpp, there is resolution like >> modex 400x300 (for this one your monitor have to support it) or lots of >> 360x480,360x400,360x360,360x240 the same in 320x... So if people want to >> get my initialization code for them, say it !! > > Most of these modes are supported in Allegro. I think you can check if some is > missing and send to Shawn the information for this mode. In this way all the > Allegro users (and that's a lot of people ;-) will be benefited. Yeah, Allegro supports all those modes (also some 256x*, 376x*, and a 400x600 resolution). The trouble is that the more severely tweaked sizes, in particular the 400x* modes, depend on some very odd frequencies that don't work on every graphics card and monitor. So they aren't generally that useful if you want to be sure your program will run on any PC... The 320x* and 360x* modes seem to work reliably on any hardware, but the larger versions of these suffer from a lack of video memory. You can double buffer a 320x400 screen, and triple buffer a 360x240, but the VGA only has enough video memory for a single page of 320x480 or 360x400, which make them less useful for realtime animation... Anyway, if you have the register values for any tweaked modes that Allegro doesn't currently support, I would love to add them! If you look in the modex.c file, there is a block of VGA_REGISTER structures for every supported mode, which are listed in the xmodes[] table. This makes it very easy to add extra resolutions, as long as you know the magic numbers... Shawn Hargreaves.