#version 450 core

layout (location = 0) in vec2 pos_min;
layout (location = 1) in vec2 pos_max;
layout (location = 2) in vec2 tex_min;
layout (location = 3) in vec2 tex_max;
layout (location = 4) in vec4 color;

layout (std140, binding = 0) uniform Camera {
    mat4 projection;
    mat4 view;
    vec2 size;
} camera;

layout (location = 1) uniform mat4 model;

out FragmentData {
    vec2 tex_coord;
    vec4 color;
} data;

void main() {
    vec2 position = vec2(0.0);
    vec2 tex_coord = vec2(0.0);

    switch (gl_VertexID) {
        case 0:
            position = vec2(pos_min.x, pos_max.y);
            tex_coord = vec2(tex_min.x, tex_max.y);
            break;

        case 1:
            position = vec2(pos_min.x, pos_min.y);
            tex_coord = vec2(tex_min.x, tex_min.y);
            break;

        case 2:
            position = vec2(pos_max.x, pos_max.y);
            tex_coord = vec2(tex_max.x, tex_max.y);
            break;

        case 3:
            position = vec2(pos_max.x, pos_min.y);
            tex_coord = vec2(tex_max.x, tex_min.y);
            break;
    }

    mat4 ortho = mat4(
        vec4(2.0 / camera.size.x, 0.0, 0.0, 0.0),
        vec4(0.0, -2.0 / camera.size.y, 0.0, 0.0),
        vec4(0.0, 0.0, 1.0, 0.0),
        vec4(-1.0, 1.0, 1.0, 1.0)
    );

    gl_Position = ortho * vec4(position, 0.0, 1.0);

    data.tex_coord = tex_coord;
    data.color = color;
}