core-graphics

I want to add a drop shadow using CALayer to a UI(Image)View. The following code works generally fine previewImage.layer.shadowColor = [[UIColor blackColor] CGColor]; previewImage.layer.shadowOffset = CGSizeMake(1.0f, 1.0f); previewImage.layer.shadowOpacity = 1.0f; previewImage.layer.shadowRadius = 8.0f; However, this only works if I create that view programmatically and add it as a subview to my main view. When that view is set up in InterfaceBuilder and defined as an IBOutlet UIImageView this does NOT work. No shadow appears. So what am I missing here? I'm not sure what the issue is - ensure

I have two bezier paths that i'd like to combine to form a union, so that I can stroke the entire outer shape. In my case, it's a speech bubble with a tail, so although it's not a complex shape it would actually be quite hard to create it using one single path. There doesn't appear to be a Core Graphics API for creating unions. Am I wrong? If I'm not, does anyone know of a library that can handle this? I've search GitHub to no avail. UIBezierPath does that if you are working with closed shapes. UIBezierPath *firstPath = [UIBezierPath bezierPath]; // build your path UIBezierPath *secondPath =

I have the following situation in my multi-monitor setup: In this example I want to position a window exactly at the coordinates depicted with the yellow arrow. All I do have however, are the coordinates of an NSView that is a subview of the contentView of an NSWindow that spans the entire (bigger,upper) secondary monitor. Here's how the global coordinate space is defined: {0,0} is the coordinate of the upper left corner of my laptop screen. (green) {-296, -1080} is the coordinate of the upper left corner of my second screen (black) {0, 800} is the coordinate of the lower left corner (no arrow

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 am trying process an image in CoreGraphics and then return the processed image back to an NSImage for saving and displaying. I have ample resources on how to perform these functions in iOS but the helper methods seem to be missing in NSImage . In iOS the class method is imageWithCGImage: , how can you do this in Mac OS? The matching method in NSImage is initWithCGImage:size: . The second argument takes the image's size in points. The factor between the size in pixels (of the CGImage) and the size in points is the scale factor. So, for example, if you have a 100×100px CGImage, and pass a size