Name

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      CLR2LUM

Purpose

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      Compute luminance from a 24-bit color value.

Category

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Calling Sequence

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      lum = clr2lum(lum)

Inputs

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      clr = 24-bit color value. in

Keyword Parameters

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Keywords

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        /BW Return the color white if lum < 128 else black.
              The gives a contrasting color for things like text.

Outputs

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      lum = returned luminance. out
        Range is Min=0., Max=255.

Common Blocks

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Notes

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Modification History

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      R. Sterner, 2004 Mar 12
      R. Sterner, 2010 Apr 30 --- Converted arrays from () to [].
  Copyright (C) 2004, Johns Hopkins University/Applied Physics Laboratory
  This software may be used, copied, or redistributed as long as it is not
  sold and this copyright notice is reproduced on each copy made. This
  routine is provided as is without any express or implied warranties
  whatsoever. Other limitations apply as described in the file disclaimer.txt.