bradparks/flump

Exports Flash .FLAs to GPU-friendly formats

Flump

Flump reads specially-constructed .fla and .xfl files saved by Flash and extracts animations and textures to allow them to be recreated in the GPU. Animations created in Flump's style will use far less texture memory per frame of animation than an equivalent flipbook animation, allowing for more expressive animations on mobile platforms. Runtimes have been written for Starling, Sparrow, Flambe and PlayN.

Creating a movie for Flump

1. Install the latest version of Adobe AIR
2. Install the Flump AIR app
3. Create a .fla in Flash CS 5, 5.5, or 6
4. Create a new item in the library and draw a shape in its canvas
5. Right-click on the item, select its properties, tick the Export for ActionScript and Export in frame 1 checkboxes and change its base class to flash.display.Sprite
6. Create a second item in the library, and drag the first into it.
7. Add additional frames in the second item, and create a classic tween moving the first item around in those frames.
8. Save the file and publish it as a swf.
9. Open the Flump app and change its import directory to the directory containing the .fla and .swf files. The .fla file should appear in the list of source files.
10. Select the .fla file and click 'Preview'. The tween you created in step 6 should start playing back in a preview window.

Details of Flump's conversion

This walks through Flump's process when it exports a single .fla/.swf file combo.

Texture creation

For each item in the document's library that is exported for ActionScript and extends flash.display.Sprite, Flump creates a texture. To do so, it instantiates the library's exported symbol from the .swf file and renders it to a bitmap.

All of the created bitmaps for a Flash document are packed into texture atlases, and xml is generated to map between a texture's symbol and its location in the bitmap.

Animation creation

For each item in the document's library that extends flash.display.MovieClip and isn't a flipbook (explained below), Flump creates an animation. It checks that for all layers and keyframes, each used symbol is either a texture, an animation, or a flipbook. Flump animations can only be constructed from the flump types.

Flipbook creation

For animations that only contain a few frames, a flipbook may be more appropriate. To create one, add a new item to the library and name the first layer in the created item flipbook. When exporting, flump will create a bitmap for each keyframe in the flipbook layer. In playback, flump will display those bitmaps at the same timing.

Compatibility

Flump works with Flash CS 5, 5.5, and 6

Reporting Bugs

To get AIR to report errors, you need to run Flump with the AIR debugger (adl). Assuming you have the free Flex SDK and ant installed on your machine:

1. Build the flump runtime

    flump/runtime$ ant -Dflexsdk.dir=/path/to/flex maven-deploy
   

2. Build the flump exporter

    flump/exporter$ ant -Dflexsdk.dir=/path/to/flex swf
   

3. Run the flump exporter

    flump/exporter$ /path/to/flex/bin/adl etc/airdesc.xml dist