High-level bindings to the Gmsh API. 

You'll need a copy of the Gmsh library, `libgmsh`, to use this crate. 

## Setting up libgmsh
This crate uses an environment variable `GMSH_LIB_DIR`. Set `GMSH_LIB_DIR` to the location of your Gmsh SDK `/lib` folder. You'll also need to adjust your `LD_LIBRARY_PATH` to be able to find the library at runtime.

### `libgmsh` installation (Linux)

Download the Gmsh SDK (v4.4.1) to the current folder and set your library variables accordingly.

```shell
$ wget http://gmsh.info/bin/Linux/gmsh-4.4.1-Linux64-sdk.tgz -O /tmp/gmsh-sdk.tar.gz
$ tar -xvf /tmp/gmsh-sdk.tar.gz
$ export GMSH_LIB_DIR=$PWD/gmsh-4.4.1-Linux64-sdk/lib/
$ export LD_LIBRARY_PATH=$GMSH_LIB_DIR:$LD_LIBRARY_PATH
$ cargo test -- --test-threads=1
```

Add the variables to your shell configuration file to avoid having to set them each time.

```
# in your .bashrc or similar 
GMSH_LIB_DIR="/path/to/your/gmsh-sdk/lib"
export GMSH_LIB_DIR

LD_LIBRARY_PATH=$GMSH_LIB_DIR:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH
```

## Getting started 
Run the examples using `cargo run --example <example>`

Gmsh is a shared resource, and Rust tests run in parallel by default, so `cargo test` 
alone will crash.  

Run the tests using `cargo test -- --test-threads=1`

You can make an alias for this command in your `~/.cargo/config` file: 
```toml 
[alias]
tt = "test -- --test-threads=1"
```

## Linking to the Gmsh library 
Gmsh ships prebuilt binary SDK libraries for Linux, MacOS, and Windows.

The download server is: [http://gmsh.info/bin/](http://gmsh.info/bin/)

Download a recent version and make sure the filename ends with `sdk`.

### Linux 
Place all dynamic library `libgmsh.so*` files where the linker can find them. 

### Windows 
Gmsh is built by MinGW on Windows, not the Visual Studio toolchain.

Because of ABI differences, the easiest way to link your Rust programs to Gmsh is to use the `x86_64-pc-windows-gnu` target and `stable-gnu` toolchain. 
```shell
rustup default stable-gnu
```

Then, download the Windows SDK zip file and ensure the linker can find the library. 

If it can't, you'll get large scary errors when you run `cargo test -- --test-threads=1`

One way to make sure the linker can find Gmsh is copying the `.lib` and `.dll` files to your `rustup` directory, e.g.: 

`~\.rustup\toolchains\stable-x86_64-pc-windows-gnu\lib\rustlib\x86_64-pc-windows-gnu\lib`