glium 0.3.3

High-level and safe OpenGL wrapper.
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#[macro_use]
extern crate glium;
extern crate glutin;

fn main() {
    use glium::{DisplayBuild, Surface};
    let display = glutin::WindowBuilder::new().build_glium().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);
    let indices = glium::index::NoIndices(glium::index::PrimitiveType::TrianglesList);

    let vertex_shader_src = r#"
        #version 140

        in vec2 position;

        uniform mat4 matrix;

        void main() {
            gl_Position = matrix * vec4(position, 0.0, 1.0);
        }
    "#;

    let fragment_shader_src = r#"
        #version 140

        out vec4 color;

        void main() {
            color = vec4(1.0, 0.0, 0.0, 1.0);
        }
    "#;

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

    let mut t = -0.5;

    loop {
        // 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, 1.0],
            ]
        };

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

        if display.is_closed() {
            break;
        }
    }
}