public function addLight(Color $col, Light $light, Vector $pos, Scene $scene, Thing $thing, Vector $reflectDir, Vector $norm)
{
$ldis = Vector::minus($light->pos, $pos);
$livec = Vector::norm($ldis);
$neatIsect = $this->testRay(new Ray($pos, $livec), $scene);
$isInShadow = $neatIsect != null && $neatIsect <= Vector::mag($ldis);
if ($isInShadow) {
return $col;
}
$illum = Vector::dot($livec, $norm);
$lcolor = Color::$defaultColor;
if ($illum > 0) {
$lcolor = Color::scale($illum, $light->color);
}
$specular = Vector::dot($livec, Vector::norm($reflectDir));
$scolor = Color::$defaultColor;
$surface = $thing->surface();
if ($specular > 0) {
$scolor = Color::scale(pow($specular, $surface->roughness()), $light->color);
}
return Color::plus($col, Color::plus(Color::times($surface->diffuse($pos), $lcolor), Color::times($surface->specular($pos), $scolor)));
}