core-graphics

I have a set of graphics that I would like to reuse within my apps. They are buttons and images with transparency. Rather than having dozens of hard-coded button images, I would love to have a single button image, and be able to assign a color to it dynamically, like the navigation bar and it's tint color. Is it possible to replace/shift the hue of a UIView? Alternatively: I know that if I overlay a transparent image over another UIView, then I can change the background color and the two images will blend together. But the transparent regions will take on the hue of the background. Is there a

Can someone point out to me if both of them are the same? I mean I have been reading info about it and this redbook here says "The color buffer itself can consist of several subbuffers. The framebuffer on a system comprises all of these buffers" here Is framebuffer then like a virtual buffer consisting of all the actual buffers ?(like depth/stencil etc) The framebuffer contains (often) the depth, stencil, color, and accumulation buffers. The color buffers are the most important part, but they are only one part. You can create more color buffers, and you can also create more framebuffers in

For an animation timing algorithm I need to supply a path as the curve. Probably a bezier curve with control points on both ends. The problem is that it seems not possible to calculate points on a CGPath because CGPathRef is opaque. Also Apple provides no mechanism to compute points on a path. Is there a library or utility class which can compute points on a bezier curve or path, for a given location like 0.5 for the middle along the path? Or let me rephrase it: If CGPath / CGPathRef makes this impossible because it is opaque, and if you only care about bezier curves, is there a way to compute

I'm trying to make an object that can draw a portion of a large (say 2048 x 1537) image using CGContextDrawImage(…). It works just fine, except that it is extremely blurry. I'm using a "drawingController" which overrides drawLayer:inContext: like this -(void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx{ CGImageRef drawImage = CGImageRetain(imageToDraw); if(drawImage) { CGRect drawRect = CGRectMake(0, 0, 1024, 748);//Just hard coded to my window size for now. CGContextSetInterpolationQuality(ctx, kCGInterpolationHigh); CGContextDrawImage(ctx, drawRect, drawImage); } CGImageRelease

I want to use Core Image for processing a bunch of CGImage objects and turning them into a QuickTime movie on macOS . The following code demonstrates what's needed, but the output contains a lot of blank (black) frames : import AppKit import AVFoundation import CoreGraphics import Foundation import CoreVideo import Metal // Video output url. let url: URL = try! FileManager.default.url(for: .downloadsDirectory, in: .userDomainMask, appropriateFor: nil, create: false).appendingPathComponent("av.mov") try? FileManager.default.removeItem(at: url) // Video frame size, total frame count, frame rate

Consider you have a line with start point (x1,y1) and end point (x2,y2). In order to draw an arrow cap to the line (in objective-c), I need to find the points of the arrow (x3,y3,x4,y4) given the angle of the arrow (45 degrees), and the length of the arrow tips (h). So given x1,y1,x2,y2,h,alpha whats x3,y3,x4,y4? Added an image explaining the question. If the answer can be in objective-c (using UIBezierpath and CGPoint) it will be much appreciated. Thanks! #import <math.h> #import <UIKit/UIKit.h> #import <CoreGraphics/CoreGraphics.h> float phi = atan2(y2 - y1, x2 - x1); // substitute x1, x2,