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UE3 Home > Mobile Home > Migrating Mobile Projects to June 2011 UDK Beta

Migrating Mobile Projects to June 2011 UDK Beta


Several significant changes have been made to the way mobile projects are handled in the June 2011 UDK Beta. These changes require special considerations when upgrading to this version from previous versions. All of the changes are outlined on this page in order to make the process of migrating your mobile projects as easy as possible.

Merged Workflow

In the June 2011 UDK Beta, the MobileGame and UDKGame directories, executables, etc. have all been merged into a single content path and workflow. This makes it much easier to develop projects across platforms, but it means that existing projects will have to make some changes in order to function properly.

  • Relocate custom content packages from MobileGame\Content directory into the UDKGame\Content directory.
  • Relocated maps from MobileGame\Content\Maps to UDKGame\Content\Maps and change the extension to .udk from .mobile.
  • Merge changes in MobileGame\Config .ini files into UDKGame\Config\Mobile .ini files. Specifically:
    • MobileGame\Config\DefaultEngine.ini -> UDKGame\Config\Mobile\MobileEngine.ini
    • MobileGame\Config\DefaultGame.ini -> UDKGame\Config\Mobile\MobileGame.ini
    • MobileGame\Config\DefaultInput.ini -> UDKGame\Config\Mobile\MobileInput.ini

For packages referencing MobileGame, those references should be fixed up automatically so existing maps should "just work". Maps with the mobile game extension will still work but its recommended that the extension be changed to .udk for consistency. New maps or maps saved using save as, will always be saved with .udk unless explicitly set.

Renamed Gameplay Classes

The MobileGame, MobilePC, and MobilePawn classes have been renamed to SimpleGame, SimplePC, and SimplePawn, respectively. If your gametype, PlayerController, or Pawn classes for your project extend directly from any of these classes or make reference to them, those references need to be updated to point to the new class names. Otherwise, you will get errors when compiling your project. The renamed classes retain all of the functionality of their predecessors so everything should continue to work as expected once the references are updated.

These classes are very basic and you should not expect a gun in first person mode to show up when using them without any modifications. When upgrading, if you are making use of a custom gametype, you will need to set your maps to use the game type they want via new Default Game Type property (described below), via the .ini file setting, or via custom script code

Specifying Gametypes

There is a new method available to specify the gametype a map should use. In the Game Type section of the World Properties, there is a Default Game Type setting which allows you to override the game type per map. Previously, in order to specify a gametype the only choices available were to set it in the .DefaultGame.ini or write script code to manually change it based on some desired criteria. These other methods are still available, but the new setting provides a simple way to set this directly through the editor.

It should be noted that, by default, SimpleGame is the default game type if no gametype is specified. SimpleGame has added the functionality to choose the gametype based on map prefixes so compatable UT-style maps that have the DM, VCTF, etc prefixes will still load the UT game types as expected and any custom map prefixes you specify in the .ini file and use for your maps will work "out of the box".

Previewing In Editor

In the editor, a new Emulate Mobile Features button ( button_emulate.png ) has been added to the toolbar. Toggling this button will enable the emulation of mobile features which will force the editor to attempt to simulate, mostly through rendering, what your game will look like on mobile. This also enables some settings like PVRTC compression when building lighting and saving packages, as well as auto flattening of materials (if material has the option set). If you do not enable this via the toolbar or through the Preferences menu using the Always optimize content for mobile command, you will encounter poor looking textures and lightmaps when previewing on mobile devices because the cooker will use a lower-quality fast compress method to compress the textures to PVRTC.

Enabling Emulate Mobile Features will change the renderer used in the editor viewports.


In addition, the Play In Editor features will use mobile input, controls, and rendering.