Want to develop for Android. Have a few basic, non-FAQ questions

Question

Hi everyone,

Recently myself and a small group of friends became interested in developing a game for a mobile platform. Originally we considered the iPhone but none of us use macs, so we decided Android would be a more realistic platform to use. Before we get started, I was hoping that I might find some answers to a couple questions so we don't waste our time if this project isn't feasible. Any help is appreciated!

1. I can't seem to find out how many programming languages Android supports. Java is obvious, but what about C+? It seems that Android supports C and C++ through Eclipse, but is that it? (I'm not the programmer for the project which is why I'm asking this. He's comfortable in C+).

2. Our game involves the use of two digital analog sticks (it's not a twin-stick shooter but it's a similar concept). It would seem that most Droid devices unfortunately don't use multi-touch though... Are there many devices out there right now which support this functionality and I'm just not seeing them, or should we possibly consider the development of a different game that would only use a single input?

3. Assuming there's no snags following those first two questions, what would you consider the best screen resolution to develop in? It seems like there are a variety of resolutions out there right now and we can't decide which is the best to use.

Again, any answers are appreciated!

Answer 1

1. You will have to use at least some Java, though you can call C++ with the newly released NDK.

2. To my knowledge at least the Droid and Nexus One support multitouch. Not sure about the newer ones.

3. I would develop for multiple screen sizes.

Chris Pruett did two very good presentations on writing real time games for android you may want to look into, they were a huge help for me.He also lightly touches on the NDK in the second one, linked below. I can only post one link since I'm a new member, but a google search for "writing real-time games for android" should turn it up.

http://bit.ly/checYY

Answer 2

1) Java is the language of the SDK. The majority of apps are and should be written in Java. The only reason for the NDK is for apps previously written in C++ that are to be ported to Android. There are downsides - it only supports compiling to 2 different CPUs (one is the Nexus one's CPU, can't remember what the other is). So if you do use C/C++ in the NDK, you are seriously limiting the number of devices you can ship to.

2) If you want to use dual analog sticks, why not display the sticks in the corners of the screen and allow the user to place their thumbs on them? You don't need hardware support.

3) Android SDK supports multiple screen resolutions so you don't necessarily need to worry about it immediately. I would aim for WVGA to start with (800x480 - Nexus One / HTC Desire).

Answer 3

1. Your first question has been answered by others already. The SDK is based on Dalvik, you're going to have to speak Java to the Android framework to do things like set up your activity, handle events, etc. You can call into a native code module built with the NDK for other things.

2. The multitouch situation on Android is dependent on hardware. Android >= 2.0 supports it in the framework, and you can use the PackageManager to query for what kind of multitouch functionality the device supports. The two you care about are FEATURE_TOUCHSCREEN_MULTITOUCH and FEATURE_TOUCHSCREEN_MULTITOUCH_DISTINCT. Some screens that only offer FEATURE_TOUCHSCREEN_MULTITOUCH have problems distinguishing precise movement when both fingers are along or near the same X or Y coordinate. This is fine for things like zoom gestures, but you might have problems doing dual-analog style controls on a device without FEATURE_TOUCHSCREEN_MULTITOUCH_DISTINCT.

3. Plan on supporting multiple resolutions. If you provide low and high resolution assets the resource system can select the appropriate ones for you automatically at runtime. More details on this here. You will still need to deal with different resolutions that do not necessarily share an aspect ratio. For example, the Droid is 480x854 while the Nexus One is 480x800.