glium 0.32.0

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, BlitTarget, Rect, BlitMask};
use glium::framebuffer::SimpleFrameBuffer;
use glium::uniforms::MagnifySamplerFilter;

mod support;

#[test]
fn blit_texture_to_window() {
    let display = support::build_display();

    let src_rect = Rect {
        left: 0,
        bottom: 0,
        width: 2,
        height: 2,
    };

    let dest_rect = BlitTarget {
        left: 1,
        bottom: 1,
        width: 2,
        height: 2,
    };

    let texture = support::build_unicolor_texture2d(&display, 0.0, 1.0, 0.0);

    let target = support::build_renderable_texture(&display);
    target.as_surface().clear_color(0.0, 0.0, 0.0, 0.0);

    texture.as_surface().blit_color(&src_rect, &target.as_surface(), &dest_rect,
                                    glium::uniforms::MagnifySamplerFilter::Nearest);

    let data: Vec<Vec<(u8, u8, u8, u8)>> = target.read();

    assert_eq!(data[1][1], (0, 255, 0, 255));
    assert_eq!(data[1][2], (0, 255, 0, 255));
    assert_eq!(data[2][1], (0, 255, 0, 255));
    assert_eq!(data[2][2], (0, 255, 0, 255));

    assert_eq!(data[0][0], (0, 0, 0, 0));

    assert_eq!(data[0][1], (0, 0, 0, 0));
    assert_eq!(data[0][2], (0, 0, 0, 0));

    assert_eq!(data[1][0], (0, 0, 0, 0));
    assert_eq!(data[2][0], (0, 0, 0, 0));

    assert_eq!(data[3][1], (0, 0, 0, 0));
    assert_eq!(data[3][2], (0, 0, 0, 0));

    assert_eq!(data[2][3], (0, 0, 0, 0));
    assert_eq!(data[1][3], (0, 0, 0, 0));

    assert_eq!(data[3][3], (0, 0, 0, 0));

    display.assert_no_error(None);
}

#[test]
fn blit_color_and_depth_buffer() {
    let display = support::build_display();

    // source frame buffer
    let src_tex_color = support::build_unicolor_texture2d(&display, 0.0, 0.5, 1.0);
    let src_tex_depth = support::build_constant_depth_texture(&display, 0.5);
    let src_frame_buffer = SimpleFrameBuffer::with_depth_buffer(&display, &src_tex_color, &src_tex_depth).unwrap();

    // destination frame buffer
    let dst_tex_color = support::build_unicolor_texture2d(&display, 0.0, 0.0, 0.0);
    let dst_tex_depth = support::build_constant_depth_texture(&display, 0.0);
    let dst_frame_buffer = SimpleFrameBuffer::with_depth_buffer(&display, &dst_tex_color, &dst_tex_depth).unwrap();

    // blit
    let src_rect = Rect {left: 0, bottom: 0, width: 2, height: 2, };
    let dst_rect = BlitTarget { left: 0, bottom: 0, width: 2, height: 2, };
    dst_frame_buffer.blit_buffers_from_simple_framebuffer(
        &src_frame_buffer,
        &src_rect,
        &dst_rect,
        MagnifySamplerFilter::Nearest,
        BlitMask::color_and_depth()
    );

    // check result
    let color_data: Vec<Vec<(u8, u8, u8, u8)>> = dst_tex_color.read();
    assert_eq!(color_data, vec![
        vec![(0, 127, 255, 255), (0, 127, 255, 255),],
        vec![(0, 127, 255, 255), (0, 127, 255, 255),],
    ]);
    // todo: how to check dst_tex_depth? There is no .read() on a DepthTexture2d...
    display.assert_no_error(None);
}