/*
 * Copyright (C) 2018 Tomasz Kramkowski <tk@the-tk.com>
 * SPDX-License-Identifier: MIT
 */
#version 330 core
out vec4 color;
in vec3 fnorm;
in vec3 fpos;
in vec2 fuv;
in vec3 lipos;

uniform sampler2D tex;

void main()
{
	vec3 objco = vec3(texture(tex, fuv));
	vec3 lico = vec3(1.0, 1.0, 1.0);

	float amb = 0.1;

	vec3 norm = normalize(fnorm);
	vec3 lidir = normalize(lipos - fpos);
	float dif = max(dot(norm, lidir), 0.0);

	float speen = max(sign(dot(lidir, norm)), 0.0);
	vec3 vwdir = normalize(-fpos);
	vec3 mid = normalize(lidir + vwdir);

	float spe = pow(max(dot(norm, mid), 0.0), 256) * speen;

	color = vec4((amb + dif + spe) * lico * objco, 1.0);
}