Modifying, coloring and dragging pre-existing images iPhone application

Question

Hi,

I am developing an iphone application which would let me modify the image by dragging other images over its top along with functionality that would let me choose a specific color from the image and replace it with some other color shades i choose. If anyone has some clue like how to actually implement it or some code, that would be great help for me to proceed in right direction

Thanks in advance :)

Answer 1

If you just want to overlay images, you can simply drag UIImageViews around and position them within the view hierarchy such that the appropriate images are overlaid one on top of the other.

For generating a new image out of those composited images, you may want to use something like CGContextDrawImage() within a UIView subclass's -drawRect: method or in a custom CGContext. You can also refer to these similar questions:

• How can we combine images and get image object from this two images in iphone apps
• Combining images

As far as selectively replacing a specific color within a UIImage, that's a commonly asked question here:

• In a UIImage (or its derivatives), how can I replace one color with another?
• How to make one color transparent on a UIImage?