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#[macro_use]
extern crate glium;
mod support;
use glium::Surface;
use glium::glutin;
use glium::index::PrimitiveType;
fn main() {
use glium::DisplayBuild;
// building the display, ie. the main object
let display = glutin::WindowBuilder::new()
.build_glium()
.unwrap();
// building the vertex buffer, which contains all the vertices that we will draw
let vertex_buffer = {
#[derive(Copy, Clone)]
struct Vertex {
position: [f32; 2],
color: [f32; 3],
}
implement_vertex!(Vertex, position, color);
glium::VertexBuffer::new(&display,
vec![
Vertex { position: [-0.5, -0.5], color: [0.0, 1.0, 0.0] },
Vertex { position: [ 0.0, 0.5], color: [0.0, 0.0, 1.0] },
Vertex { position: [ 0.5, -0.5], color: [1.0, 0.0, 0.0] },
]
)
};
// building the index buffer
let index_buffer = glium::IndexBuffer::new(&display, PrimitiveType::TrianglesList,
vec![0u16, 1, 2]);
// compiling shaders and linking them together
let program = program!(&display,
140 => {
vertex: "
#version 140
uniform mat4 matrix;
in vec2 position;
in vec3 color;
out vec3 vColor;
void main() {
gl_Position = vec4(position, 0.0, 1.0) * matrix;
vColor = color;
}
",
fragment: "
#version 140
in vec3 vColor;
out vec4 f_color;
void main() {
f_color = vec4(vColor, 1.0);
}
"
},
110 => {
vertex: "
#version 110
uniform mat4 matrix;
attribute vec2 position;
attribute vec3 color;
varying vec3 vColor;
void main() {
gl_Position = vec4(position, 0.0, 1.0) * matrix;
vColor = color;
}
",
fragment: "
#version 110
varying vec3 vColor;
void main() {
gl_FragColor = vec4(vColor, 1.0);
}
",
},
100 => {
vertex: "
#version 100
uniform lowp mat4 matrix;
attribute lowp vec2 position;
attribute lowp vec3 color;
varying lowp vec3 vColor;
void main() {
gl_Position = vec4(position, 0.0, 1.0) * matrix;
vColor = color;
}
",
fragment: "
#version 100
varying lowp vec3 vColor;
void main() {
gl_FragColor = vec4(vColor, 1.0);
}
",
},
).unwrap();
// the main loop
support::start_loop(|| {
// building the uniforms
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],
[0.0, 0.0, 0.0, 1.0f32]
]
};
// drawing a frame
let mut target = display.draw();
target.clear_color(0.0, 0.0, 0.0, 0.0);
target.draw(&vertex_buffer, &index_buffer, &program, &uniforms, &Default::default()).unwrap();
target.finish().unwrap();
// polling and handling the events received by the window
for event in display.poll_events() {
match event {
glutin::Event::Closed => return support::Action::Stop,
_ => ()
}
}
support::Action::Continue
});
}