glium 0.6.3

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

#[cfg(feature = "image")]
extern crate image;

use std::io::Cursor;

#[cfg(not(feature = "image"))]
fn main() { println!("This example requires the `image` feature to be enabled"); }
#[cfg(feature = "image")]
fn main() {
    use glium::{DisplayBuild, Surface};
    let display = glium::glutin::WindowBuilder::new().build_glium().unwrap();

    let image = image::load(Cursor::new(&include_bytes!("../tests/fixture/opengl.png")[..]),
                            image::PNG).unwrap();
    let texture = glium::texture::Texture2d::new(&display, image);

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

    implement_vertex!(Vertex, position, tex_coords);

    let vertex1 = Vertex { position: [-0.5, -0.5], tex_coords: [0.0, 0.0] };
    let vertex2 = Vertex { position: [ 0.0,  0.5], tex_coords: [0.0, 1.0] };
    let vertex3 = Vertex { position: [ 0.5, -0.25], tex_coords: [1.0, 0.0] };
    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;
        in vec2 tex_coords;
        out vec2 v_tex_coords;

        uniform mat4 matrix;

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

    let fragment_shader_src = r#"
        #version 140

        in vec2 v_tex_coords;
        out vec4 color;

        uniform sampler2D tex;

        void main() {
            color = texture(tex, v_tex_coords);
        }
    "#;

    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],
            ],
            tex: &texture,
        };

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

        for ev in display.poll_events() {
            match ev {
                glium::glutin::Event::Closed => return,
                _ => ()
            }
        }
    }
}