bits.toPixels()

Not very long ago you had to upload your App Store screenshots in many different resolutions for all the different iOS devices. A real pain. Fortunately, Apple realized this and simplified the screenshot upload process a lot. Now you only need to upload screenshots for the 5.5" iPhone and 12.9" iPad displays, and automatic scaling will be done for remaining devices with lower resolutions. It's recommended to grab your screenshots from a physical device, but what do you do if you don't have a 5.5" iPhone? Well, instead of buying a new device or scaling lower resolution graphics you can use the Corona Simulator to get the high resolution screenshots you're looking for. This is how I do it for my Corona SDK apps on my Windows machine, and my example assumes that your screenshots are taken in portrait mode and that your app is primarily designed for iPhone rather than iPad. You must of course also have a monitor that can handle the resolution of the screensho...

Working with display objects and display groups in Corona SDK is fairly straightforward. Every Corona developer probably knows the basics of this and how you can organize your display objects in a hierarchy of display groups. All this is also pretty well documented by Corona Labs right here , so I'm not gonna go into details about any of this. Instead I'll show you how I've created a simple helper class called DisplayManager which I find very useful when it comes to leverage the concept of layers and to keep track of all display objects to avoid creating memory leaks by not cleaning up the display objects properly. What I want the DisplayManager class to help me with is basically a few things, that otherwise requires quite a lot of attention when coding: Leverage the concept of visual layers, and encapsulate functionality concerning layers in an object-oriented way, making it easy to extend when needed. Make sure that all display objects are cleaned up as they shou...

When working with sprites in Corona SDK I've quite often run into a problem with sprite sheet frames occasionally overlapping each other. When I say occasionally I mean that it doesn't happen for every new sprite I create even though the same sprite sheet is used, and it doesn't happen on all device resolutions. This is what it might look like when the overlap happens. Not pretty... The sprite's image sheet Sprites in action, pixel overlapping between frames To work around this problem in the past, I've just padded my sprite images with a couple of transparent pixels so that the possible overlap won't be visible even though it might still be there. This has caused some additional work both to set up the sprite sheet images, as well as calculating the frames' positions within the sheet. So I figured I was gonna look for another solution to be able to create sprite sheets without padding that still look good. Tough luck it turned out. The pixel o...