AndEngine BitmapTextureAtlas extension

Last few days I played with AndEngine, an open source, free, games framework for Android. I'm not sure yet if AndEngine will save time building new games.

Anyhow, one weird part in AndEngine is the way you load all the resources into a single canvas. You have to define the location of each resource on the canvas, and if you change the resource size you have to recalculate everything.

Here is a simple extension to BitmapTextureAtlas that calculate everything automatically and saves you the trouble of positioning the resources on the canvas.

public class BitmapTextureAtlasEx extends BitmapTextureAtlas {
 int mUsedWidth;
 
 public BitmapTextureAtlasEx(int width, int height, TextureOptions options) {
  super(width, height, options);
  
  mUsedWidth = 0;
 }
 
 public TextureRegion appendTextureAsset(Context c, String assetPath) {
  TextureRegion region = BitmapTextureAtlasTextureRegionFactory.createFromAsset(
         this, c, assetPath, mUsedWidth, 0);
  mUsedWidth += region.getWidth();
  
  return region;
 }
 
 public TiledTextureRegion appendTiledAsset(Context c, String assetPath, int tiledColumns, int tiledRows) {
  TiledTextureRegion region = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(
         this, c, assetPath, mUsedWidth, 0, tiledColumns, tiledRows);
  mUsedWidth += region.getWidth();
  
  return region;
 } 
}

And this is how to use it (in the onLoadResources funcation):

mTexture = new BitmapTextureAtlasEx(1024, 128, TextureOptions.BILINEAR_PREMULTIPLYALPHA);
      
mTextureRegion = this.mTexture.appendTextureAsset(this, "texture.png");
mTiledRegion = this.mTexture.appendTiledAsset(this, "tile.png", 1, 1);

Free resources for applications

This post is a work in progress.

Here are few places I've found for useful for free resources. You should verify if the specific resource license fit your needs.

Free fonts:
*. http://www.fontsquirrel.com/ (verify the copy rights per font, most are not really free)
*. http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=OFL (read the OFL license first)

Free clip arts:
*. http://www.openclipart.org/.
*. Huge list of sites that contain free images.

Free music/sound affects:
*. http://www.freesound.org - Creative common license.
*. There are many sites that looks OK, just search for 'free sound effects'.

A bit off-topic - royalty free resources (not free):
*. Music loops
*. Tons of resources: The Marketing Guide for Game Developer

Monetizing Android applications

In a recent talk I've heard by Itay Rokni of StartApp.com he listed the various monetizing options Android developer has (to date):

• In app ads - Ads inside the application: banners, full page, leads generators etc. See for example AdMob.


• Paid apps - The user pay to get the application. Not free options.


• Freemium - Basic application is free, the user can buy the full application or in-app buy more features.


• Notification bar ads - Ads that appear not inside the application, but in the notification bar. For example see airpush.com.


• Search icon - Create a search icon after app installation. The provider pay per installation or revenue share. For example see StartApp.com

Few notes if you're using In app ads:

• Trust no one - AdMob is the industry benchmark and every says 'we're better than AdMob'. I found this statement to be almost always wrong.


• Use mediation layer - Use mediation layer such as AdWhirl to control which ad networks you're using. Ad networks go up and down, it's better to control the follow of ads dynamically and not depend on updating the APK in the market.