I was just wondering if most games on the iPhone are done in OpenGL ES as opposed to using Quartz and Core Animation. Are Quartz and Core Animation mostly used for just creating slick interfaces? Or if there is a point with games where OpenGL probably has to be used over using other tools? ...
Hey all, I'm trying to create a simple iPhone input device shaped like a disk, ony half of which is viewable on screen. The idea is this disk would be spun, and the selection would be the menu item in the middle when the disk stops spinning. Any idea what the best way of implementing such a thing would be? I'm reading up on Quartz2D and...
I have a ViewController class where I use some CG____ structures. There is no import for Core Graphics. So I thought that's fine and tried to start using CALayer without importing Quartz framework. It didn't work, and I hat do import it. I think I missed the point here why I have to import this one, but not the other one? ...
When I try this myUIImageView.bounds.size.width = 50.0f; then I get an error: invalid lvalue in assignment But when I do this, it compiles. Although it's a lot of extra-work CGRect newRect = myUIImageView.bounds; newRect.size.width = 50.0f; myUIImageView.bounds = newRect; Although that compiles, nothing will happen. My UIImageView...
As the background for one of the views in my app, I'd like to draw a fairly simple rectangular border just inside its frame. This would essentially be a rectangular gradient: a black line around the frame, fading to white about 10-20 pixels in. Unfortunately, as far as I can tell, Core Graphics doesn't provide rectangular gradients (eith...
How do you subclass CALayer so that you return a layer with styling properties already set? So that: MyCustomLayer *layer = [MyCustomLayer layer]; would create a layer with these properties; layer.backgroundColor = sweetBackgroundColor.CGColor; layer.borderColor = sweetBorderColor.CGColor; layer.borderWidth = 2.0; layer.cornerRadiu...
I have a Mac Plugin for viewing images. It's originally written in Quickdraw, and I'm trying to move it to Quartz. My current problem is the origin. In QD, the origin is (sensibly) the upper left corner of the plugin rectangle. In Quartz, it appears to be one screen height below the top of the plugin rectangle (not including firefox but...
Hi, I am writing an iPhone application in Objective-C that utilizes some custom drawing in views and I would like to benchmark various revisions of my code to see what really helps. I was planing on doing this by setting up a new application, adding my custom drawing code to the drawRect: method of the view, then, in a for loop in the v...
I am a beginner at iPhone programming, and would like to draw a line to the phone screen for the purpose of study using Quartz and UIKit. How do I start drawing? ...
Does anyone have an example of how to draw the blue "unread dot" used in Apple's Mail App? This one in specific: http://bit.ly/3A7XxD Drawing an ellipse is straight forward with Quartz2d, but the subtle use of shadows+gradients make this look really 3d. ...
I'm experimenting with drawing on the iPhone by manually creating parts of the UI for my application (In this case a graph). Essentially, I want to draw a rectangle with rounded corners, a drop-shadow, and a semi-transparent gradient as the fill of the rectangle. Here is a screen shot of my photoshop mockup: I've gotten has far as crea...
I'm loading a PDF file into a UIView and I would like to know how to change the background color or the font color of the PDF. I've tried several things using Quartz, but no success. How can I accomplish this? ...
I've modified the ViewTransitions app to use kCAScrollHorizontally. I've set transition in the app delegate to use kCATransitionPush rather than kCATransitionFade. However, I still get fading in and out. How can I get the views to slide in landscape just like the Star Trek app (http://itunes.apple.com/WebObjects/MZStore.woa/wa/viewSoft...
How would you go about animating the drawing of a line in a UIView on the iPhone? Is this possible? It can be drawn but can it easily be animated so it appears to be hand drawn? ...
Before I ask my questions, this is from Apple's documentation re: how to determine the width of a string using Quartz: If text measurements are important to your application, it is possible to calculate them using Quartz 2D functions. However, you might first consider using ATSUI, whose strength is in text layout and measurement. ATSU...
So I tried to use the Quartz CGImageCreateWithMaskingColors function, but he only problem is that it masks the color range you are selecting. I want to mask everything but the color range I am selecting. For instance, I want to show all red colors in a picture but remove the other channels (Green and Blue). I am doing this in Objecti...
Hello, I move a UIImageView with touchesbegan, touchesmoved, touchesended. It works well, but is the touches get also applied to other UIImageViews, laying around. How do I lock touching activity while moving the UIImageView? I've tried this with a Boolean Value, but it hasn't worked, because touchesmoved get called every time the UIIm...
Hello, ist there any chance to build a water effect with Quartz on the iPhone? Something similar to this one: ...
I'm trying to develop a complex painting application on the iPhone. I'm currently drawing using Quartz (e.g. CGContext...). Unfortunately the Quartz overhead is just too slow for the type of drawing I'm doing, and I'm porting to OpenGL calls using the GLPaint example as a reference point. Is there a way to get a UIImage/CGImage from t...
I have an app which allows the user to select an image from camera or photo library. It then places that image in a ImageView. I am then using Quartz to grab the image from that image view and render it along with some basic overlays etc. The issue is that when the image is picked from the camera, or from the camera roll Quartz draws ...