When you have finished creating compositions in an After Effects project you need to export them to a format that can be used by a You.i Engine based application.
To do this, select You.i: Export All Compositions from the Composition menu. You will then be presented with a dialog box enabling you to select a directory for the exported files. The directory selection dialog box will default to the same directory as the AE project file.
Although not required, most You.i Engine applications, including the samples in the SDK, follow a de-facto directory hierarchy:
The After Effects project files are located in the AE directory, image and binary files in the assets directory, build scripts and supporting files in the build directory and the application source code in the src directory.
Typically the assets directory is used as the location for the exported files.
If it doesn't already exist a directory called layout is created in the export directory. If the compositions in the project are located in folders in the project panel then the folders will be created as sub directories of the layout directory. If there are no folders in the project then a directory named default is created for the exported files. For each composition there are two binary files created:
- ProjectName_CompositionName.layout Contains data that represents the composition and its layers and their sources including the text of text layers. Layers with visibility toggled 'off' WILL NOT be exported. Visible layers with 0% opacity WILL be exported.
- ProjectName_CompositionName.timeline Contains data that represents the layer properties being animated, the markers, their associated keyframes and times.
The default naming convention concatenates the After Effects project name with the composition name to aid in identifying files in projects with more than a trivial number of files and compositions.
In addition, each pair of binary layout and timeline files has a corresponding pair of text based log files with the same base name but with an additional .log extension:
These files provide a human readable format of the data in the binary files and can be used to troubleshoot design and development issues during a project, although they are not needed to build the application.
During the export, a log window is displayed listing any warnings.
As the compositions are exported, some aspects of the layouts and timelines are checked for correctness or potential problems. As these are encountered they are logged to the log window. It is good practice to eliminate the source of the warning prior to using the exported files in the building of the application. You can perform a dry run export by selecting the You.i: Validate All Compositions from the Composition menu. This does everything described above except actually write the exported files. You can use this to identify, via the warnings, the potential problem areas in your project and then when you are comfortable, do the real export.
All Compositions in All Projects in Folder
The above features operate on one After Effects project at a time. Some applications have many After Effects project files and sometimes there is a need to export them all in one fell swoop. This can be done via the You.i: Export All Compositions in All Projects in Folder and the You.i: Validate All Compositions in All Projects in Folder menu options. These require an additional step of specifying the folder in which the After Effects project files are located.
Typically the fonts used in a You.i Engine application are carefully chosen by the design team and distributed to all the members of the team for use in After Effects. During the export process, the font files used in the After Effects project are copied from where After Effects uses them (typically an operating system directory) to the You.i Engine export directory. They are renamed with a You.i specific, platform independent convention (based on Adobe's OpenType naming convention):
Typically the originalExtension will be .otf or .ttf.
When the project's binary layout files are used by the application, these fonts will be loaded automatically.
If a project team member opens an After Effects file and does not have the fonts specified in the After Effects project file (i.e. the ones the previous designer saved with), After Effects will display a warning ("a layer has missing dependencies"), display the font family name and style name in square brackets in the AE Character panel and substitute a different font for display in its UI. It is not recommended to export under these conditions. If you do, the font file copied will not be the original, carefully chosen file but the one that After Effects has chosen as a substitute. In this case, the You.i Engine AE Plug-in chooses a slightly different file name on copy to the the export directory to help you identify this situation:
There will also be a warning in the export log window:
"After Effects is substituting a font file that doesn't match the saved text layer's specified font family and style."