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|
module GraphicsColor
( Color(..)
, colorTable
, withColor
) where
import GraphicsTypes
import GraphicsPicture(withRGB)
import Ix(Ix)
import Array(Array,array,(!))
----------------------------------------------------------------
-- The interface
----------------------------------------------------------------
-- Paul wants me to use ROYGBIV - but I don't know what Indigo is
-- and I want Black and White
data Color
= Black
| Blue
| Green
| Cyan
| Red
| Magenta
| Yellow
| White
deriving (Eq, Ord, Bounded, Enum, Ix, Show, Read)
colorList :: [(Color, RGB)]
colorTable :: Array Color RGB
withColor :: Color -> Picture -> Picture
----------------------------------------------------------------
-- The implementation
----------------------------------------------------------------
colorList =
[ (Black , RGB 0 0 0)
, (Blue , RGB 0 0 255)
, (Green , RGB 0 255 0)
, (Cyan , RGB 0 255 255)
, (Red , RGB 255 0 0)
, (Magenta , RGB 255 0 255)
, (Yellow , RGB 255 255 0)
, (White , RGB 255 255 255)
]
colorTable = array (minBound, maxBound) colorList
withColor c = withRGB (colorTable ! c)
----------------------------------------------------------------
-- The end
----------------------------------------------------------------
|
