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.
Documentation
#[macro_use]
extern crate glium;
use glium::Surface;

#[path = "../book/tuto-07-teapot.rs"]
mod teapot;

fn main() {
    let event_loop = glium::winit::event_loop::EventLoop::builder()
        .build()
        .expect("event loop building");
    let (window, display) = glium::backend::glutin::SimpleWindowBuilder::new()
        .with_title("Glium tutorial #9")
        .build(&event_loop);

    let positions = glium::VertexBuffer::new(&display, &teapot::VERTICES).unwrap();
    let normals = glium::VertexBuffer::new(&display, &teapot::NORMALS).unwrap();
    let indices = glium::IndexBuffer::new(&display, glium::index::PrimitiveType::TrianglesList,
                                        &teapot::INDICES).unwrap();

    let vertex_shader_src = r#"
        #version 150

        in vec3 position;
        in vec3 normal;

        out vec3 v_normal;

        uniform mat4 matrix;

        void main() {
            v_normal = transpose(inverse(mat3(matrix))) * normal;
            gl_Position = matrix * vec4(position, 1.0);
        }
    "#;

    let fragment_shader_src = r#"
        #version 150

        in vec3 v_normal;
        out vec4 color;
        uniform vec3 u_light;

        void main() {
            float brightness = dot(normalize(v_normal), normalize(u_light));
            vec3 dark_color = vec3(0.6, 0.0, 0.0);
            vec3 regular_color = vec3(1.0, 0.0, 0.0);
            color = vec4(mix(dark_color, regular_color, brightness), 1.0);
        }
    "#;

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

    #[allow(deprecated)]
    event_loop.run(move |ev, window_target| {
        match ev {
            glium::winit::event::Event::WindowEvent { event, .. } => match event {
                glium::winit::event::WindowEvent::CloseRequested => {
                    window_target.exit();
                },
                // We now need to render everyting in response to a RedrawRequested event due to the animation
                glium::winit::event::WindowEvent::RedrawRequested => {
                    let mut target = display.draw();
                    target.clear_color_and_depth((0.0, 0.0, 1.0, 1.0), 1.0);

                    let matrix = [
                        [0.01, 0.0, 0.0, 0.0],
                        [0.0, 0.01, 0.0, 0.0],
                        [0.0, 0.0, 0.01, 0.0],
                        [0.0, 0.0, 0.0, 1.0f32]
                    ];

                    let light = [-1.0, 0.4, 0.9f32];

                    let params = glium::DrawParameters {
                        depth: glium::Depth {
                            test: glium::draw_parameters::DepthTest::IfLess,
                            write: true,
                            .. Default::default()
                        },
                        .. Default::default()
                    };

                    target.draw((&positions, &normals), &indices, &program,
                                &uniform! { matrix: matrix, u_light: light }, &params).unwrap();
                    target.finish().unwrap();
                },
                // Because glium doesn't know about windows we need to resize the display
                // when the window's size has changed.
                glium::winit::event::WindowEvent::Resized(window_size) => {
                    display.resize(window_size.into());
                },
                _ => (),
            },
            // By requesting a redraw in response to a AboutToWait event we get continuous rendering.
            // For applications that only change due to user input you could remove this handler.
            glium::winit::event::Event::AboutToWait => {
                window.request_redraw();
            },
            _ => (),
        }
    })
    .unwrap();
}