Why is Core Graphics drawing this outline? - ios

Question

For some reason Core Graphics is drawing an extra outline around my path. Here is some sample code.
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextClearRect(context, rect);
CGContextSaveGState(context);
float startRadius = 71.0;
float startAngle = 135, endAngle = 405;
endAngle = startAngle + (endAngle - startAngle)*drawValue;
int clockwise = 0;
if(isTargetFiller) {
if(drawValue < 0.0)
clockwise = 1;
startAngle = 270;
endAngle = 405;
endAngle = startAngle + (endAngle - startAngle)*drawValue;
}
CGPoint center = CGPointMake(75, 75);
CGContextMoveToPoint(context, center.x, center.y);
CGContextAddArc(context, center.x, center.y, startRadius, DEG_2_RAD(startAngle),
DEG_2_RAD(endAngle), clockwise);
CGContextClosePath(context);
CGContextClip(context);
UIImage *bigImage = [UIImage imageNamed:#"CTracker_Full.png"];
CGPoint topLeftOffset = CGPointMake(
(self.bounds.size.width - bigImage.size.width) / 2,
(self.bounds.size.height - bigImage.size.height) / 2);
[bigImage drawAtPoint: topLeftOffset blendMode:kCGBlendModeNormal alpha:1.0];
CGContextSetBlendMode (context, kCGBlendModeMultiply);
float green = 1.0;
float red = 0.0;
if(value > 0.5) {
green = 1.0 - (value - 0.5) / 0.5;
red = (value - 0.5) / 0.5;
}
UIColor *tintColor = [UIColor colorWithRed:red green:green blue:0.0 alpha:1.0];
CGContextSetFillColor(context, CGColorGetComponents(tintColor.CGColor));
CGContextFillRect(context, rect);
CGContextSetBlendMode(context, kCGBlendModeDestinationIn);
[bigImage drawAtPoint:topLeftOffset blendMode:kCGBlendModeDestinationIn
alpha:1.0];
Here is what it is currently drawing:
As you can see, there is an outline around the actual shape that leads to the center of the image.

Answer 1

Figured it out myself right after posting this. Hopefully this will help someone else.
Changed the last little bit of code to:
UIColor *tintColor = [UIColor colorWithRed:red green:green blue:0.0 alpha:1.0];
CGContextSetFillColor(context, CGColorGetComponents(tintColor.CGColor));
CGContextFillRect(context, rect);
CGContextRestoreGState(context);
CGContextSaveGState(context);
CGContextSetBlendMode(context, kCGBlendModeDestinationIn);
[bigImage drawAtPoint:topLeftOffset blendMode:kCGBlendModeDestinationIn alpha:1.0];