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lightning-sunbird  0.9+nobinonly
nsCSSColorUtils.h
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00037 
00038 
00039 #ifndef __nsCSSColorUtils_h
00040 #define __nsCSSColorUtils_h
00041 
00042 #include "nsColor.h"
00043 
00044 // "Sufficient contrast" is determined by
00045 // "Techniques For Accessibility Evalution And Repair Tools".
00046 // See http://www.w3.org/TR/AERT#color-contrast
00047 #define NS_SUFFICIENT_LUMINOSITY_DIFFERENCE 125000
00048 #define NS_LUMINOSITY_DIFFERENCE(a, b) \
00049           PR_ABS(NS_GetLuminosity(a) - NS_GetLuminosity(b))
00050 
00051 // Weird color computing code stolen from winfe which was stolen
00052 // from the xfe which was written originally by Eric Bina. So there.
00053 // To determin colors based on the background brightness
00054 void NS_Get3DColors(nscolor aResult[2], nscolor aBackgroundColor);
00055 
00056 // To determine colors based on the background brightness and border color
00057 void NS_GetSpecial3DColors(nscolor aResult[2],
00058                            nscolor aBackgroundColor,
00059                            nscolor aBorderColor);
00060 
00061 // Determins brightness for a specific color
00062 int NS_GetBrightness(PRUint8 aRed, PRUint8 aGreen, PRUint8 aBlue);
00063 
00064 // Get Luminosity of a specific color. That is same as Y of YIQ color space.
00065 // The range of return value is 0 to 255000.
00066 PRInt32 NS_GetLuminosity(nscolor aColor);
00067 
00068 // function to convert from RGB color space to HSV color space 
00069 void NS_RGB2HSV(nscolor aColor,PRUint16 &aHue,PRUint16 &aSat,PRUint16 &aValue);
00070 // function to convert from HSV color space to RGB color space 
00071 void NS_HSV2RGB(nscolor &aColor,PRUint16 aHue,PRUint16 aSat,PRUint16 aValue);
00072 
00073 #endif