quartz-graphics

With CGContextSetLineWidth(context, 1) the width is almost alwayas at least 2 pixels instead 1 QQCandleStickLayer.m -(id)init { self = [super init]; if(self != nil) { self.delegate = self; self.opaque = NO; } return self; } - (void)drawLayer:(CALayer*)layer inContext:(CGContextRef)context{ CGContextSetLineWidth(context, 1.0f); CGContextSetAllowsAntialiasing(context, false); CGContextSetShouldAntialias(context, false); CGContextSetInterpolationQuality(context,kCGInterpolationNone); CGContextSetShadowWithColor(context, CGSizeMake( 0.0, 0.0 ), 0, NULL); CGContextMoveToPoint(context, self.bounds

My object a sub class of NSObject has CALayer instance variable. I use it for drawing and caching content with its delegate set to my object. But for some reason drawLayer:inContext: method NEVER gets called. Whereas actionForLayer:forKey: delegate method does get called implying the delegate is getting set properly with layer.delegate = self in the object's init method. Any suggestions on what is preventing my layer drawing method drawLayer:inContext: from getting called ? I am called the [layer setNeedDisplay] often. So I guess it is some fundamental error. drawLayer:inContext: won't get

How can I scan links in a PDF Document? Do I have to use Quartz? Which methods/functions? Yes, you need to use Quartz. You have to parse it out from the PDF. This guide can help you. http://developer.apple.com/library/ios/#documentation/GraphicsImaging/Conceptual/drawingwithquartz2d/dq_pdf_scan/dq_pdf_scan.html#//apple_ref/doc/uid/TP30001066-CH220-TPXREF101 I recommend reading the PDF specification so you will know what to look for. The links are stored in the Annotations object so you will need some software to parse those. 来源： https://stackoverflow.com/questions/3717775/how-to-scan-links-in

I have a little sketch program that I've managed to throw together using Quartz2D, but I'm very new to the iOS platform and I'm having trouble figuring out how to allow the user to save their sketch. I have a CGContextRef that contains the sketch, how can I save it so that it can later be retrieved? Once it's saved, how can I retrieve it? Thanks so much in advance for your help! I'm going to continue reading up on this now... There are different types of CGContexts. You are most likely having a screen based context, but you would need either a bitmapContext or a pdfContext, to create a bitmap

I tried creating the Siri chat bubble in core graphics. I am at a stage where I can draw the shape. I am stuck with the color's here. Wanaa get the border color and the fill color code. here is what I did so far.. - (void)drawInContext:(CGContextRef)context { CGRect rect = gradientRectFrame; CGFloat radius = 30; CGFloat originBufferX = 0.0; CGFloat originBufferY = 0.0; CGFloat rightAngleTriangleWidth = 20.0; CGFloat rightAngleTriangleHeight = 20.0; CGFloat fullRectWidth = rect.size.width; CGFloat fullRectHeight = rect.size.height; CGPoint pointZero = CGPointMake(originBufferX, fullRectHeight);

I want to let user draw a signature on iPhone screen, so I add a subclass of UIView and add some code to its 'touchesMoved' method. -(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; firstTouch = [touch locationInView:self]; CGSize mySize = CGSizeMake(5, 5); UIGraphicsBeginImageContext(mySize); CGContextRef ctx = UIGraphicsGetCurrentContext(); CGContextBeginPath(ctx); CGContextSetRGBFillColor(ctx, 1, 0, 0, 1); CGContextAddRect(ctx, CGRectMake(0, 0, 5, 5)); CGContextFillPath(ctx); UIImage *redRect = UIGraphicsGetImageFromCurrentImageContext()

I'm trying to programmatically recreate the indented button look that can be seen on a UINavigationBarButton. Not the shiny two tone look or the gradient, just the perimeter shading: It looks like an internal dark shadowing around the entire view perimeter, slightly darker at the top? And then an external highlighting shadow around the lower view perimeter. I've played a bit with Core Graphics, and experimented with QuartzCore and shadowing with view.layer.shadowRadius and .shadowOffset, but can't even get the lower highlighting to look right. I'm also not sure where to start to achieve both a