Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!mcgill-vision!bloom-beacon!mit-eddie!bu.edu!bu-cs!mirror!prism!rob
From: rob@prism.TMC.COM
Newsgroups: comp.sys.ibm.pc
Subject: Re: Why no graphics in text mode?
Message-ID: <206900161@prism>
Date: 16 Jan 90 20:17:00 GMT
References: <25820@cup.portal.com>
Lines: 13
Nf-ID: #R:cup.portal.com:-2582000:prism:206900161:000:639
Nf-From: prism.TMC.COM!rob    Jan 16 15:17:00 1990


   It's possible - difficult and hardware-specific, but possible - to 
put graphics on the screen in text mode by reprogramming the character set. 
This can be done on the EGA and VGA, though not on the CGA. The 'line 
drawing' characters defined in the IBM extended ASCII set allow this to a 
limited extent, but by defining your own characters, you can create the 
illusion of bit-mapped graphics in text mode.

   IBM put out an EGA demo program several years ago that used this
technique. I believe it was called FantasyLand.

   A good book dealing with this is Richard Wilton's 'Programmer's
Guide to the PC and PS/2 Video Systems'.