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Talk:Text Mode Doom

1,300 bytes added, 08:20, 21 June 2005
smmu's textmode implementation
-- [[User:Jdowland|Jdowland]] 21:31, 20 Jun 2005 (UTC)
 
I've lost the original page and images I had, unfortunately.
 
The system works by using the extended ASCII text mode "gradient" characters (there are ~4-5 of them). When the palette is set, the hue and brightness of each colour is calculated from the palette entries. The hue is then used to select the text-mode colour to use for the character, while the brightness is used to select the character to use.
 
The extended mode ascii characters used are (descriptions I 'think' are correct):
 
* "space" character (32): all background
* 0xb0: 20% foreground
* 0xb1: 40% foreground
* 0xb2: 60% foreground
* 0xdb: 80% foreground
 
The original version of the SMMU textmode renderer used black as the background, and the selected colour as the foreground (ie, 5 steps). I later improved on it by adding greater colour depth and using the background colour. Basically text mode has two sets of colours; the second are the same as the first but brighter (1 is blue, 9 is "bright blue"). So instead of going from black -> colour, I made it go black -> colour -> bright colour (the first stage having black background + colour foreground, the second stage having colour background + bright colour foreground). This effectively doubles the colour depth.
 
[[User:Fraggle|Fraggle]] 08:20, 21 Jun 2005 (UTC)
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