Haptic authoring begins with the Studio desktop app. With this tool, you author the haptic clips that will be played in your application via the Studio frameworks, libraries, and plug-ins.
The general workflow for authoring haptics is:
- Load an audio file into the Studio desktop app.
- Run the Audio Analyzer to generate the initial haptic effect.
- Audition the haptic effect on the Studio mobile app on your phone. If necessary, edit the haptic effect in and validate the changes with the Studio mobile app.
- Export the final haptic clip to disk.
NOTE: Even if your application has no audio, or you want to create haptics for events that have no corresponding audio, you will still need to use some kind of audio file as a starting point when authoring haptics with the Studio desktop app. This process is faster—and the results will likely be more rich and interesting—than designing haptic effects purely by hand.
The Studio desktop app requires that you sign in with your Lofelt credentials (the same you used when you signed up for Lofelt Studio) in order to use the application. This will happen the first time you run the application. Once you’ve signed into the application, you will remain signed in even if you quit the application and relaunch it.
To sign-in, enter your Lofelt credentials where prompted:
If you wish to sign out of the Studio desktop app, go to File > Sign-out:
When you launch the Studio desktop app, the Welcome screen presents you with two options:
- New Project: Start a new authoring session by loading audio.
- Recent Project: Resume work on a previous session by reloading a saved project.
To start a new authoring project in the Studio desktop app, simply load an audio file. From the Home screen, there are two ways to do this:
- Click “New Project from Audio” and select an audio file.
- Drag your desired audio file from the Finder/Explorer and drop it into the “Drop an audio file here” box.
To resume work on a previous project, you can:
- Click the project shown in the “Recent Project” list on the right side of the Home screen.
- Choose File > Open Project… or press CMD(CTRL)+O to select the right Project Folder.
NOTE: When opening a previously-saved project, the original audio that was uploaded to the servers during audio analysis will be used.
Included in the Lofelt Studio download is a collection of content you can use in your own apps. This content is located in the download at
/Studio Desktop/Example Projects/. Here you will find some additional sub-folders which collect the examples into various categories. Inside of these folders, you will find an audio file, its associated haptic clip, and the Studio project used to create the haptic.
One of the most powerful aspects of the Studio desktop app is its Audio Analyzer. The Audio Analyzer creates extremely detailed haptics from any audio file, saving you lots of time and effort in designing haptic feedback.
In the left panel, you can adjust several algorithm parameters. (For more information about those parameters, see the “Adjusting Audio Analyzer Parameters” section in “Advanced Authoring Techniques.”)
Once you have set the parameters, click “Analyze” at the top of the list. The Studio desktop app processes the audio and then displays a set of envelopes in the main editor window.
You can re-run Analysis as often as you want. You can change the analysis parameters and see how they affect the resulting haptics.
It’s important to understand how the envelopes created by the Studio desktop app actually feel on the platform where your app will run. Use the Studio mobile app to play back the haptics directly on an Apple or Android phone. If you haven’t already, download the Lofelt Studio mobile app from the Apple App Store or Google Play Store. You can also just search for “Lofelt Studio” on those stores to find the app.
For the Studio mobile app to know what haptic file you want to audition, you must make a connection between the Studio desktop app and the Studio mobile app. This is done via a quick scan of a QR code as follows:
On the envelope display screen in Studio desktop app, click on the button in the bottom-right corner that looks like a mobile phone. A QR code will appear.
The QR code will be different for each authoring session you conduct with the Studio desktop app.
On your phone, launch the Studio mobile app. At the bottom of the app are a series of selector buttons. Tap on the “Audition” button:
NOTE: If this is your first time using the Audition feature of the Studio mobile app, the app might ask you for permission to access the device’s camera. Please confirm to allow access, otherwise the app will not be able to use the camera for scanning the QR code.
Point the phone’s camera at the QR code shown in the Studio desktop app window of your desktop computer.
Once the QR code is read, a connection is established between the Studio desktop app and Studio mobile app. The screen then changes to show a large “play” button.
Press and hold the play button to both feel the haptic experience and hear the corresponding audio. Playback will stop when you remove your finger from the button.
NOTE: For the best experience, use headphones to hear the audio while you feel the haptic on the phone. By using headphones, you avoid creating any extra vibrations from the phone’s internal speaker, which might influence your evaluation of the pure haptic experience generated by the phone’s actuator.
With the Studio desktop app, it is possible to manually edit the haptics in case the Audio Analyzer didn’t create the exact results you were looking for. The desktop app provides a graphical interface for editing the haptic curves, and you can immediately feel the results of any changes you make on your connected phone. Read the “Manually Editing Haptics” section for details.
After validating the haptic experience with the Studio mobile app, export the haptic information from the Studio desktop app as a haptic clip.
To export, choose File > Export Haptic or press CMD(CTRL)+E:
A window will appear in Studio desktop asking what type of haptic you’d like to export. The options are as follows:
- Haptic: This is the device-agnostic format used by all the Lofelt Studio frameworks, libraries, and plug-ins. It will generate a file with a
- Ahap: This is the device-specific format used by Apple’s Core Haptics API. It will generate a file with an
By default, the haptic clip will use the same name as the audio file you provided. This helps keep audio files and their associated haptic clips neatly organized on your computer. So, for example, if you used an audio file called
footstep1.wav, the default file name for the haptic clip will be
footstep1.haptic and the AHAP file would be
footstep1.ahap. If you prefer, you can customize the haptic clip file name. You can also choose a destination folder for the new haptic clip in the dialog box that appears.
NOTE: When using the Studio mobile app to audition haptics, you will be feeling the quality of a .haptic clip. The resulting haptics might feel slightly different when exported as an AHAP file and played via Apple’s Core Haptics API due to how Core Haptics handles amplitude and transients differently from Lofelt Studio.
You can save the current state of the Studio desktop app as a project. This will enable you to open the project in the future and resume work on the haptic. You can then continue refining, auditioning, and exporting new haptic clips as needed.
To save, choose File > Save or File > Save as… from the menu, or press CMD(CTRL)+S for “Save” or CMD(CTRL)+SHIFT+S for “Save as…”. If saving for the first time or using “Save as…”, a dialog box will appear where you can create or select a folder where your project should be saved—click “Save” to complete the save.
If you use Save as… to create a new copy of your project, a new QR code will be generated for that project. This allows you to compare the haptic you create in the new project against the version in the older project by scanning each of their unique QR codes.