Added a mask to the image category

Vortec4800 · Sep 14, 2012 · 38519cf · 38519cf
1 parent 0fa4f9b
commit 38519cf
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/Example/UIImage+KGNoise.m b/Example/UIImage+KGNoise.m
@@ -27,6 +27,8 @@ - (UIImage *)imageWithNoiseOpacity:(CGFloat)opacity andBlendMode:(CGBlendMode)bl
                                                  kCGImageAlphaPremultipliedLast);
     CGColorSpaceRelease(colorSpace);
 
+	CGContextSaveGState(context);
+
     // Flip context
     CGContextTranslateCTM(context, 0, self.size.height * self.scale);
     CGContextScaleCTM(context, self.scale, -self.scale);
@@ -36,6 +38,10 @@ - (UIImage *)imageWithNoiseOpacity:(CGFloat)opacity andBlendMode:(CGBlendMode)bl
     // Draw the image
     [self drawAtPoint:CGPointMake(0.0, 0.0)];
 
+	CGContextRestoreGState(context);
+
+	CGContextClipToMask(context, CGRectMake(0.0, 0.0, self.size.width * self.scale, self.size.height * self.scale), [self CGImage]);
+
     // Noise on top
     [KGNoise drawNoiseWithOpacity:opacity andBlendMode:blendMode];