glium 0.29.1

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.
Documentation 
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#[macro_use]
extern crate glium;

fn main() {
    #[allow(unused_imports)]
    use glium::{glutin, Surface};

    let event_loop = glutin::event_loop::EventLoop::new();
    let wb = glutin::window::WindowBuilder::new();
    let cb = glutin::ContextBuilder::new();
    let display = glium::Display::new(wb, cb, &event_loop).unwrap();

    #[derive(Copy, Clone)]
    struct Vertex {
        position: [f32; 2],
    }

    implement_vertex!(Vertex, position);

    let vertex1 = Vertex { position: [-0.5, -0.5] };
    let vertex2 = Vertex { position: [ 0.0,  0.5] };
    let vertex3 = Vertex { position: [ 0.5, -0.25] };
    let shape = vec![vertex1, vertex2, vertex3];

    let vertex_buffer = glium::VertexBuffer::new(&display, &shape).unwrap();
    let indices = glium::index::NoIndices(glium::index::PrimitiveType::TrianglesList);

    let vertex_shader_src = r#"
        #version 140

        in vec2 position;
        out vec2 my_attr;      // our new attribute

        uniform mat4 matrix;

        void main() {
            my_attr = position;     // we need to set the value of each `out` variable.
            gl_Position = matrix * vec4(position, 0.0, 1.0);
        }
    "#;

    let fragment_shader_src = r#"
        #version 140

        in vec2 my_attr;
        out vec4 color;

        void main() {
            color = vec4(my_attr, 0.0, 1.0);   // we build a vec4 from a vec2 and two floats
        }
    "#;

    let program = glium::Program::from_source(&display, vertex_shader_src, fragment_shader_src, None).unwrap();

    let mut t = -0.5;
    event_loop.run(move |event, _, control_flow| {

        match event {
            glutin::event::Event::WindowEvent { event, .. } => match event {
                glutin::event::WindowEvent::CloseRequested => {
                    *control_flow = glutin::event_loop::ControlFlow::Exit;
                    return;
                },
                _ => return,
            },
            glutin::event::Event::NewEvents(cause) => match cause {
                glutin::event::StartCause::ResumeTimeReached { .. } => (),
                glutin::event::StartCause::Init => (),
                _ => return,
            },
            _ => return,
        }

        let next_frame_time = std::time::Instant::now() +
            std::time::Duration::from_nanos(16_666_667);
        *control_flow = glutin::event_loop::ControlFlow::WaitUntil(next_frame_time);

        // we update `t`
        t += 0.0002;
        if t > 0.5 {
            t = -0.5;
        }

        let mut target = display.draw();
        target.clear_color(0.0, 0.0, 1.0, 1.0);

        let uniforms = uniform! {
            matrix: [
                [1.0, 0.0, 0.0, 0.0],
                [0.0, 1.0, 0.0, 0.0],
                [0.0, 0.0, 1.0, 0.0],
                [ t , 0.0, 0.0, 1.0f32],
            ]
        };

        target.draw(&vertex_buffer, &indices, &program, &uniforms,
                    &Default::default()).unwrap();
        target.finish().unwrap();
    });
}