Xref: news2.mv.net comp.os.msdos.djgpp:5478 From: Shawn Hargreaves Newsgroups: comp.os.msdos.djgpp Subject: Re: Allegro - tile graphics Date: Thu, 27 Jun 1996 17:57:00 +0100 Organization: The University of York, UK Lines: 31 Message-ID: NNTP-Posting-Host: tower.york.ac.uk Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII In-Reply-To: <4qp09n$75t@frodo.smartlink.net> To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp On Tue, 25 Jun 1996, Nicholas Marrone wrote: > 1) When viewing the screen, there is a 1 pixel black line between the > first and second tile rows, and also one between the 1rst and 2nd .... > blit(data[map[ver][hor]].dat, screen, 0, 0, > hor * 20, ver * 20, hor * 20 + 19, ver * 20 + 19); You are passing the wrong size parameters to blit(). The last two parameters should be the width and height of the area to blit, ie. both 20, regardless of where on the screen you are blitting the image. > 2) Although I'm sure my video card has enough memory, I cannot make a > virtual screen that is 640x480 wide! The largest I can get is 640x409, Mode-X can only address 256k of video memory, regardless of how much you have in your card, because it uses the standard VGA memory addressing scheme. If you want to access more than 256k, you'll have to use an SVGA mode. Unfortunately there isn't a standard way of accessing low resolution SVGA modes, but SciTech have implemented these in UniVBE for most cards. I think UniVBE will give you a 320x240 resolution with a 640x480 virtual screen on almost anything, and this will work with Allegro's VESA drivers. But then you'd need UniVBE to run your program... /* * Shawn Hargreaves. Why is 'phonetic' spelt with a ph? * Check out Allegro and FED on http://www.york.ac.uk/~slh100/ */