Top "Cgcontext" questions

The CGContextRef opaque type represents a Quartz 2D drawing destination.

Drawing dashed and continuous lines

I need to draw lines; some are dashed and others are continuous. I cannot know which are dashed and which …

objective-c cocoa-touch ios line cgcontext
Drawing in CATiledLayer with CoreGraphics CGContextDrawImage

I would like to use a CATiledLayer in iPhone OS 3.1.3 and to do so all drawing in -(void)drawLayer:(…

iphone core-graphics cgcontext catiledlayer
CGBitMapContextCreate Method Causes Compiler Warning Xcode 5 not Xcode 4

I just updated Xcode from version 4.6.2 to 5.0, and after doing a method in my project (created in Xcode 4.6.2) is suddenly …

ios xcode cgcontext xcode5 cgbitmapcontextcreate
Why does my CGContext-drawn circle suck?

I have a custom table view cell that is intended to draw a circle like the iPhone’s Mail.app …

iphone objective-c core-graphics cgcontext
CGContext: how do I erase pixels (e.g. kCGBlendModeClear) outside of a bitmap context?

I'm trying to build an eraser tool using Core Graphics, and I'm finding it incredibly difficult to make a performant …

ios objective-c core-graphics cgcontext
Best way to draw circle on top of UIImageView IOS

I have a UIImageView that shows a picture the user has just taken with the camera. On that image i …

ios uiview uiimageview cgcontext cashapelayer
CGBitmapContextCreate : unsupported parameter combination

I am trying to create a 8-bit grayscale context as follows : CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray(); CGContextRef context = CGBitmapContextCreate( data, m_width, …

ios cgcontext
cgcontext rotate rectangle

guys! I need to draw some image to CGContext.This is the relevant code: CGContextSaveGState(UIGraphicsGetCurrentContext()); CGContextRef ctx = UIGraphicsGetCurrentContext(); CGRect …

ios rotation core-graphics cgcontext rect
draw CALayer into a CGContext

I have the following code: CGContextRef context = UIGraphicsGetCurrentContext(); CGContextSaveGState(context); CALayer *sublayer = [CALayer layer]; sublayer.backgroundColor = [UIColor orangeColor].CGColor; sublayer.…

calayer cgcontext
Custom CALayer - invalid context 0x0

I'm trying to build an app that use layers, my app structure is UIView --> UIScrollView --> UIView …

ios5 calayer cgcontext quartz-core