#version 330 core

in vec2 tex_coords;

out vec4 frag_color;

uniform sampler2D depth_map;
uniform float near;
uniform float far;

float linearize_depth(float depth)
{
    float z = (depth+1.0)*0.5;
    return((2.0*near*far)/(far+near-z*(far-near)));
}

void main(void)
{
    float depth = texture(depth_map, tex_coords).r;

    /* frag_color = vec4(vec3(depth), 1.0); */

    /* NOTE(pryazha): For visual debugging of perspective projection light */
    frag_color = vec4(vec3(linearize_depth(depth)/far), 1.0);
}