Designing and Creating Graphics - Beginning iOS6 Games Development - page 324

In Figure A-13 , we see the screen size of our three devices. For the two iPhone versions, the white
game areas with the thick gray borders are the same size in terms of points, 300x300. Of course,
the iPhone 4 version is 600x600 pixels versus the 300x300 pixels of the iPhone 3GS, but because
we are concerned with finding the best size for our images, we are concerned with pixels and not
points. The size of the game area on the right for the iPad 1 and iPad 2 is 720 pixels (and points).
So, to calculate the size of each coin image, we simply divide by 5. We get 60x60 for the 3GS,
120x120 for the iPhone 4, and 144x144 for the iPads. Figure A-14 shows one of the coin images in
all three sizes.
Figure A-14. Coin in three different sizes
In Figure A-14 , we see three different versions of the file coin_circle0029. By providing these
different resolutions, we have ensured that our images get rendered at a 1:1 ratio for the number of
pixels in the image versus the number of pixels on the screen. This assures we are doing our part
to render these images as best we can. Next, let's take a look at some of the tools used to create
graphic assets.
Tools
The following is a short description of three open source graphics tools that can be used to create
compelling graphic assets. These are the tools I have used to create the majority of the art files for
this topic. Not only are these tools open source but they run on Windows, OS X, Linux, and probably
other platforms as well.
GIMP
The GNU Image Manipulation Program (or GIMP) is an open-source image editing application.
It provides Adobe Photoshop-like functionality with the low, low price of free. During game
development, it is necessary to have an image-manipulation program for many tasks.
Figure A-15 shows an example of the GIMP.