layout/base/nsCSSColorUtils.h

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  37
  38 /* functions that manipulate colors */
  39
  40 #ifndef __nsCSSColorUtils_h
  41 #define __nsCSSColorUtils_h
  42
  43 #include "nsColor.h"
  44
  45 // "Sufficient contrast" is determined by
  46 // "Techniques For Accessibility Evalution And Repair Tools".
  47 // See http://www.w3.org/TR/AERT#color-contrast
  48 #define NS_SUFFICIENT_LUMINOSITY_DIFFERENCE 125000
  49 #define NS_LUMINOSITY_DIFFERENCE(a, b) \
  50           PR_ABS(NS_GetLuminosity(a) - NS_GetLuminosity(b))
  51
  52 // Weird color computing code stolen from winfe which was stolen
  53 // from the xfe which was written originally by Eric Bina. So there.
  54 // To determin colors based on the background brightness
  55 void NS_Get3DColors(nscolor aResult[2], nscolor aBackgroundColor);
  56
  57 // To determine colors based on the background brightness and border color
  58 void NS_GetSpecial3DColors(nscolor aResult[2],
  59                            nscolor aBackgroundColor,
  60                            nscolor aBorderColor);
  61
  62 // Determins brightness for a specific color
  63 int NS_GetBrightness(PRUint8 aRed, PRUint8 aGreen, PRUint8 aBlue);
  64
  65 // Get Luminosity of a specific color. That is same as Y of YIQ color space.
  66 // The range of return value is 0 to 255000.
  67 PRInt32 NS_GetLuminosity(nscolor aColor);
  68
  69 // function to convert from RGB color space to HSV color space
  70 void NS_RGB2HSV(nscolor aColor,PRUint16 &aHue,PRUint16 &aSat,PRUint16 &aValue);
  71 // function to convert from HSV color space to RGB color space
  72 void NS_HSV2RGB(nscolor &aColor,PRUint16 aHue,PRUint16 aSat,PRUint16 aValue);
  73
  74 #endif