gistfile1.txt

@implementation AMLayer

- (void)visit {
  CGRect mask = self.maskArea;
  BOOL shouldMask = !CGSizeEqualToSize(mask.size, CGSizeZero);
  
  if(shouldMask) {
    CGFloat s = CC_CONTENT_SCALE_FACTOR();
    CGPoint origin = CGPointMake(mask.origin.x*s, mask.origin.y*s);
    CGSize size = CGSizeMake(mask.size.width*s, mask.size.height*s);

    glEnable(GL_SCISSOR_TEST);
    glScissor(origin.x, origin.y, size.width, size.height);
  }
  [super visit];
  if(shouldMask) {
    glDisable(GL_SCISSOR_TEST);
  }
}

@end