Inner Shadow on Label

gistfile1.txt

- (void)drawTextInRect:(CGRect)rect
{
	[super drawTextInRect:rect];
	
	CGContextRef ctx = UIGraphicsGetCurrentContext();
	
	NSString *fontName = self.font.fontName;
	CGFloat fontSize = self.font.pointSize;
	
	CTFontRef font = CTFontCreateWithName((__bridge CFStringRef)fontName, fontSize, NULL);
	
	int charCount = [self.text length];
	CGGlyph glyphs[charCount];
	CGRect rects[charCount];
	CGSize advances[charCount];
	
	CTFontGetGlyphsForCharacters(font, (const unichar*)[self.text cStringUsingEncoding:NSUnicodeStringEncoding], glyphs, charCount);
	CTFontGetAdvancesForGlyphs(font, kCTFontDefaultOrientation, glyphs, advances, charCount);
	CTFontGetBoundingRectsForGlyphs(font, kCTFontDefaultOrientation, glyphs, rects, charCount);
	
	CGMutablePathRef glyphPath = CGPathCreateMutable();
	
	int totalwidth = 0, maxheight = 0;
	CGPoint textPosition = CGPointZero;
	
	CGFloat ascent = CTFontGetAscent(font);
	
	for (int i=0; i < charCount; i++)
	{
		totalwidth += rects[i].size.width;
		maxheight = maxheight < rects[i].size.height ? rects[i].size.height : maxheight;
		
		CGPathRef oneGlyphPath = CTFontCreatePathForGlyph(font, glyphs[i], NULL);
		
		CGAffineTransform offsetTransform = CGAffineTransformMake(1, 0, 0, 1, textPosition.x, self.bounds.size.height - ascent);
		
		CGPathAddPath(glyphPath, &offsetTransform, oneGlyphPath);
		
		textPosition.x += advances[i].width;
		textPosition.y += advances[i].height;
	}
	
	CGPathRef innerpath = CGPathCreateCopy(glyphPath);
	
	// adding a rect around the inner path inverts it with EOF fill rule
	CGPathAddRect(glyphPath, NULL, self.bounds);
	
	// flip the coordinate system
	CGContextSetTextMatrix(ctx, CGAffineTransformIdentity);
	CGContextTranslateCTM(ctx, 0, self.bounds.size.height);
	CGContextScaleCTM(ctx, 1.0, -1.0);
	
	CGContextAddPath(ctx, innerpath);
	CGContextClip(ctx);
	
	[[UIColor blueColor] set];
	CGContextFillRect(ctx, self.bounds);
	
	CGContextAddPath(ctx, glyphPath);
	CGColorRef color = [UIColor colorWithWhite:0 alpha:0.8].CGColor;
	CGContextSetShadowWithColor(ctx, CGSizeMake(3, 3), 4, color);
	CGContextEOFillPath(ctx);
	
	
	CGPathRelease(glyphPath);
}