Created
August 2, 2013 09:11
Convert a UIColor color to its grayscale equivalent
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#import <UIKit/UIKit.h> | |
@interface UIColor (Grayscale) | |
- (UIColor *)grayscale; | |
@end |
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#import "UIColor+Grayscale.h" | |
@implementation UIColor (Grayscale) | |
- (UIColor *)grayscale { | |
CGFloat red = 0; | |
CGFloat blue = 0; | |
CGFloat green = 0; | |
CGFloat alpha = 0; | |
if ([self getRed:&red green:&green blue:&blue alpha:&alpha]) { | |
return [UIColor colorWithWhite:(0.299*red + 0.587*green + 0.114*blue) alpha:alpha]; | |
} else { | |
return self; | |
} | |
} | |
@end |
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