glium 0.36.0

Elegant and safe OpenGL wrapper. Glium is an intermediate layer between OpenGL and your application. You still need to manually handle the graphics pipeline, but without having to use OpenGL's old and error-prone API. Its objectives: - Be safe to use. Many aspects of OpenGL that can trigger a crash if misused are automatically handled by glium. - Provide an API that enforces good pratices such as RAII or stateless function calls. - Be compatible with all OpenGL versions that support shaders, providing unified API when things diverge. - Avoid all OpenGL errors beforehand. - Produce optimized OpenGL function calls, and allow the user to easily use modern OpenGL techniques.
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# Loading SPIR-V shaders with Glium

In this example, we start with a vertex and fragment shader in separate GLSL files, `shader.vert` and `shader.frag`.
Since we want to load SPIR-V shaders, we first compile the GLSL shaders to SPIR-V.
For that, we use `glslangValidator` which you can download [here](https://github.com/google/shaderc/blob/main/downloads.md).

We compile them to SPIR-V modules (`.spv` files) as follows:
```sh
glslangValidator -G shader.vert -o vert.spv
glslangValidator -G shader.frag -o frag.spv
```

Then we can load them in Glium using:
```rust
ProgramCreationInput::SpirV(SpirvProgram::from_vs_and_fs(
    SpirvEntryPoint { data: include_bytes!("vert.spv"), entry_point: "main" },
    SpirvEntryPoint { data: include_bytes!("frag.spv"), entry_point: "main" },
))
```

But SPIR-V also allows having multiple entry points in the same module.
For this example we link fragment and vertex shaders together:
```sh
spirv-link vert.spv frag.spv -o shader.spv
```
And then we load them from the same `.spv` file:
```rust
let spirv = SpirvEntryPoint { data: include_bytes!("shader.spv"), entry_point: "main" };
let program = glium::Program::new(
    &display,
    ProgramCreationInput::SpirV(SpirvProgram::from_vs_and_fs(spirv, spirv)),
).unwrap();
```

Note: It's not a problem that both entry points are named `main`, since they are distinguished by their shader type:
```sh
$ spirv-cross shader.spv --reflect | jq .entryPoints
[
  {
    "name": "main",
    "mode": "vert"
  },
  {
    "name": "main",
    "mode": "frag"
  }
]
```

But we could also rename the entry points:
```sh
glslangValidator -G shader.vert --source-entrypoint main -e main_vs -o vert.spv
glslangValidator -G shader.frag --source-entrypoint main -e main_fs -o frag.spv
spirv-link vert.spv frag.spv -o shader.spv
```

Then we would load it like this:
```rust
let data = include_bytes!("shader.spv");
ProgramCreationInput::SpirV(SpirvProgram::from_vs_and_fs(
    SpirvEntryPoint { data, entry_point: "main_vs" },
    SpirvEntryPoint { data, entry_point: "main_fs" },
))
```