Graphics_Demo

Comments

• Mike Green Posts: 23,101

  2007-06-27 03:51 edited 2007-06-27 03:51

  Graphics_Palette just tells you what value you need to produce a particular color on the display. The actual choice of a color is a two step process. Each pixel can have one of 4 colors chosen from a palette. The display is organized into 16x16 tiles of pixels and each tile can have a different palette. There's an array of palettes (called colors) each entry of which consists of a long word and the 4 bytes of the long word contain the color information (from Graphics_Palette) for one of the 4 colors. I'm not sure, but I think that Graphics_Demo uses colors[noparse][[/noparse] 0 ] for all of the tiles. Try changing colors[noparse][[/noparse] 0 ] to some different value after the initialization routine (where it says 'init colors).
• lilbowser Posts: 2

  2007-06-27 04:20 edited 2007-06-27 04:20

  This is what was there
  

  'init colors
    repeat i from 0 to 63
      colors[i] := $00001010 * (i+4) & $F + $2B060C02[/i]
  
• Mike Green Posts: 23,101

  2007-06-27 04:35 edited 2007-06-27 04:35

  Yes, I know. It looks like the 64 color palettes are initialized with one color code = $2B, another = $06. The third color varies from $4C, $5C, ... , $FC, $0C, ... $3C repeated every 16 palette entries and the fourth similarly varies from $42, $52, ... , $F2, $02, ... $32. Look at Graphics_Palette for the colors that match these values.
• rsum Posts: 2

  2007-06-27 08:18 edited 2007-06-27 08:18

  Its not an ntsc/pal issue?