Path: utzoo!attcan!uunet!wuarchive!udel!bunnell From: bunnell@udel.edu (H Timothy Bunnell) Newsgroups: comp.os.minix Subject: Re: Graphics Lib, GUI, ..., "X Lit"? Keywords: Minix V1.5, EGA, VGA, Drivers, GUI Message-ID: <30331@nigel.ee.udel.edu> Date: 13 Sep 90 13:47:28 GMT References: <69159@sgi.sgi.com> Sender: usenet@ee.udel.edu Organization: University of Delaware Lines: 43 Nntp-Posting-Host: dewey.udel.edu In article <69159@sgi.sgi.com> fanj@remb6489.wpd.sgi.com (Fan Jiao) writes: >While hearing people talking about X for Minix, it seems that >at least we need some graphics primitives to start with playing >with graphics stuff. > I agree. Some primitives need to be included in the kernel. It is not obvious how extensive kernel support should be or how support should be distributed within the kernel. Here are some things to consider in trying to set up graphics for Minix: 1. Should a graphics kernel support switching the hardware in and out of graphics and text modes, or always run in bitmapped graphics mode with no hardware character generation or scrolling? 2. How (if at all) should user processes get access to video ram? A. Directly read from or write to something like /dev/screen? B. Open some kind of /dev/screen giving it the address of a (user space) memory block the the program will write to directly as a virtual screen and let /dev/screen update the real video ram from the virtual screen? C. Load all graphics capabilities into /dev/console and have it look like a graphics terminal (e.g., Tek 4010 :-)? Each of these has several obvious advantages and disadvantages. 3. Should character generation be limited to a single bit-plane on EGA/VGA to be as fast as possible at the expense of versatility in color? >First of all, I think we need at least two drivers, EGA and VGA. Also >we may consider necessary to include an "extended lib"(non ANSI) like >MicroSoft C's one. Then we can begin talking GUI. > EGA and VGA are sufficiently alike that a single driver might handle both. I don't see how one could avoid Hercules support as well, and a CGA driver would follow easily from the HGC. >-- >- Fan Jiao -- Tim Bunnell