Color « graphics « iPhone iPad Media Q&A

1. "kCGColorSpaceGenericRGB" is deprecated on iPhone?    stackoverflow.com

I'm trying to get bitmap context with the following code:

GContextRef MyCreateBitmapContext (int pixelsWide,
                   ...

2. Comparing colors in Objective-C    stackoverflow.com

I'm trying to determine if two colors are equivalent, using code written in Objective-C. I'm using this snippet of code to determine if the two colors are equivalent (currently for debugging purposes)

 ...

3. Set image colors from core graphics    stackoverflow.com

I have image in png file like this. I load it and draw in drawRect method. Can I change colors of image in Core Graphics or Quartz on iphone? ...

4. ColorMap in iPhone Core Graphics?    stackoverflow.com

I have a monochrome image with 256 levels of grayscale. I want to map each level to a specific color and apply to the image to get a colored image as ...

5. Is there a penalty for mixing color spaces? (Core Graphics)    stackoverflow.com

If I'm writing drawing code in Core Graphics on Mac OS X or iPhone OS, I can set the active fill color to red by calling:

CGContextSetRGBFillColor(context, 1.0, 0.0, 0.0, 1.0); // ...

6. Iphone convert color image to 2bit image (black-white)    stackoverflow.com

I have been poundering this for the last few days.. I need help to convert a color image to "black and white", not grayscale. I what to do this with the iPhone SDK ...

7. How to get color components of a CGColor correctly    stackoverflow.com

I have a UILabel with black color; i am writing the following code to get black color's components.

UIColor *aColor = [aLabel.textColor retain];
const CGFloat* components = CGColorGetComponents(aColor.CGColor);
CGColorSpaceRef colorSpace=CGColorSpaceCreateDeviceRGB();

8. How can I make colors in Adobe Illustrator line up more closely with colors on the iPhone 4?    stackoverflow.com

Images with vibrant purple colors in them look washed out and faded on the iPhone 4's screen. This effect happens with other colors too. Also, purples in Illustrator look almost blue ...

9. What does yellow tinting represent when using "color misaligned images" on iPhone/iOS    stackoverflow.com

so--i switched on "color misaligned images" to improve drawing performance in our app (Spot). The documentation states:

Puts a magenta overlay over images whose source pixels aren't aligned ...

10. How to paint a good RGB color map?    stackoverflow.com

I'm trying to paint a full RGB color map that eventually will allow a user to select a color by tapping that visual map at any point. My current code is ...

11. Color TdCalendarView rows    stackoverflow.com

I am using TdCalendarView code by Tinyfool in my project in which all calendar is designed using core graphics.I want to color rows of this calendar with two alternate colors.How can ...

12. Is there a way to quickly modify individual color values in an image?    stackoverflow.com

For example, I have a CGImageRef and I want to shift all pixels which are red to orange. Or to put it in other words: I want to apply a value ...

13. Displaying and array of colors using CGShading    stackoverflow.com

I have an array of CGColors that I need to display across a path. I tried doing this with a CGGradient, but I don't want the colors the blend between ...