Trying HoloToolkit sharing examples

Getting started with HoloToolkit sharing services is a bit overwhelming, mainly because it’s divided into both in HoloToolkit and HoloToolkit-Unity repositories.

Server

First of all, Microsoft doesn’t provide compiled version of the server, so you’ll need to compile it yourself. Fortunately, they provide all the necessary scripts and guides to do this; basically clone the main HoloToolkit repository and follow the instructions on the getting started guide to setup the build environment then run “BuildAll.bat” script.

If you already updated to Visual Studio 2017 and don’t have VS2015 anymore, this part is a bit annoying. VS2017 changed some paths that build scripts depend and you either have to change scripts by hand, then edit all the solutions and upgrade their targets, or simply install VS2015. I tried the first option, but compiling takes lots of time and at some point installing VS2015 just became more viable solution.

While compiling I also made a huge rookie mistake, didn’t add Java paths and spent some time to understand what’s wrong. So following “Setup the Build Environment” part of the “Getting Started” guide word-by-word is to your advantage.

When the compiling is done, there will be a new folder called SDK on your Sharing folder. Open cmd or PowerShell and go to Server folder under the SDK. You have to options to run the server;

• SharingService.exe -local : Runs the server like any other program. Server is closed when you close the command prompt.
• SharingService.exe -install : Installs the server as a service and constantly runs it on the background. Note that you might get “Error 5 : Access Denied” for this command, following this StackOverflow answer for Server folder with using “SERVICE” instead of “SYSTEM” keyword solves the issue.

So we run the service, but how can we check if it actually works? Open SDK/Tools/SessionManager folder, select the appropriate architecture for your computer and run SessionManager.UI.exe. This is a small tool that helps you to control currently running sessions and connected devices, it’ll be really handy while you are first setting your Unity scene for the sharing.

Client

Open HoloToolkit-Unity project and open one of the examples, preferably “SharingTest” for the first try. All 3 Tests are explained here. Cool thing is, sharing library works on Unity Editor as well as the emulator, so you don’t need to deploy the app to HoloLens for testing.

Play the scene on the Unity Editor, if everything was correct, you’ll see something like this;

But what if everything wasn’t correct? SharingStage script, which is located under the Sharing prefab has a property called “Show Detailed Logs”. For the “SharingTest” scene it’s on by default, if not, enable it and follow your logs for finding the issue. You can also use SessionManager tool to check if the service is running and your app is connected to it.

If this scene works, you can also test the “SharingSpawnTest” scene, which adds / removes prefabs on / from the scene with voice commands on HoloLens and keyboard inputs on Unity Editor (“spawn basic” (I), “spawn custom” (O) and “delete object” (M)). Before creating VS project for the emulator, beware that you should change “Server Address” property of SharingStage script in Managers/Sharing object. HoloLens emulator lives in a virtual machine, hence has it’s own localhost and you need to use your computers IP address to ensure communication between the emulator and the server.

Where to go from here? Well, the best tutorial on this so far is at Microsoft’s Mixed Reality Academy. Besides that, there aren’t many sources on this topic yet, so for now you’ll need to explore the HoloToolkit yourself.