Menge Unity

This project serves as an example for integrating the Menge crowd simulation framework with the Unity game engine.

Running the Demo

Make sure you have already cloned the main Menge repository. This Unity project will reference simulation specifications in the examples directory.

These instructions assume the 64-bit version of the Unity Editor. If you're using the 32-bit version, read the instructions below on 32/64-bit issues.

1. Clone this repository (or better yet, fork it so you can submit improvements back as a pull request).
2. Start the Unity Editor.
3. Open a new project and select the root directory of your clone as the containing folder.
4. The Unity 3D view should show four blocks. These are the obstacles for the 4square example in $MengeRoot$\examples\core\4square.
5. Open the SimController script for editing.
6. Edit line 27 so the mengeRoot variable points to the path on your system where the Menge source is located. Make sure that the path includes a final \ character.
7. Save SimController.cs and return to the editor.
8. Hit the play button.

Dependencies for Making Changes

The contents of this repository are sufficiently self-contained to run a demo (assuming you can provide scenario specification files). However, it may be necessary for you make modifications on what this simple example can do; changes that go beyond just Unity. The integration of Menge into Unity is based on two things:

1. Menge itself (specifically, the MengeCore.dll). Clone from here
2. Menge C-Sharp Wrapper. Clone from here

Both of these projects will produce dlls for you to include in the Unity project. The MengeCore.dll produced by the Menge project should go in $MengeUnity$\assets\Plugins (see note below for details on 32/64-bit issues). The MengeCS.dll produced by the second project should go in the $MengeUnity$\assets\Scripts folder.

32/64-bit issues

When using external dlls in Unity, it is important to make sure the dlls are built to the same build environment as the application. For a 32-bit application, you need 32-bit dlls. For a 64-bit application, you need a 64-bit dll. This seems straightforward, but there is a wrinkle that might catch you. The Unity Editor is one of the applications you develop and, on modern machines, it is most likely a 64-bit application. So, even if your final application you're using Unity to produce is a 32-bit application, to develop it you'll need both a 64-bit and 32-bit version of the MengeCore.dll.

If you look in the Plugins folder, you'll note there are two subfolders containing, apparently identical files: x86 and x86_64 both contain copies of MengeCore.dll. As the directory names suggeset, they are not actually identical. The former is a 32-bit dll and the latter is a 64-bit dll. We provide both and then configure them inside Unity so that it uses the right one in the right context. For this to work, they must be named the same.

If you make changes to Menge, you'll need to build Menge twice: one as 32-bit and one as 64-bit.
In order for the magic to work, the files must have identical names. This can lead to confusion and requires care that the right build ends up in the right directory. If you end up putting the wrong dll in the wrong directory, it will become immediately apparent -- the dll will fail to load.

Contributing

Please feel free to contribute to this example. The first major step is to replace cylinders with interesting pedestrians. We would really appreciate it if those better versed in Unity than we are could help us flesh this out into a more fully-featured visualization of Menge simulations.