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Screen colour settings

At present, PCVideo assumes each graphics card has either 2 or 16 colours available. On startup it therefore adjusts the video colour palette so that all colours it may use are in the lowermost 16 registers (the EGA has 64 colour registers - though 16 colours only available at 640x350 resolution - and the VGA has more than that).

For certain types of graphics adapters with more than 2 tones, PCVideo also adjusts the displayed colours for readability on the screen. When the Center's dialogues were first moved to colour systems, the IBM PCjr - long since discontinued - was the only one available, so colour combinations were chosen on the basis of yielding readable text on the PCjr's display. However, colour definitions in succeeding IBM systems have altered enough that some previously acceptable combinations became almost unreadable. PCVideo therefore now adjusts several of the colours as shown under their respective adapters, as follows: