toytracer/color.h

#ifndef COLOR_H
#define COLOR_H

#include <vector>
#include <iostream>
#include <cmath>
#include <cstddef>

#include "vec3.h"
#include "util.h"

void write_color(std::ostream &out, Color pixel_color, int sample_per_pixel) {
    auto r = pixel_color.x();
    auto g = pixel_color.y();
    auto b = pixel_color.z();

    auto scale = 1.0 / sample_per_pixel;
    r = std::sqrt(scale * r);
    g = std::sqrt(scale * g);
    b = std::sqrt(scale * b);

    out << static_cast<int>(256 * clamp(r, 0.0, 0.999)) << " "
        << static_cast<int>(256 * clamp(g, 0.0, 0.999)) << " "
        << static_cast<int>(256 * clamp(b, 0.0, 0.999)) << "\n";
}

void write_color_vec(std::vector<unsigned char>& vec, std::size_t i, Color pixel_color, int sample_per_pixel) {
    auto r = pixel_color.x();
    auto g = pixel_color.y();
    auto b = pixel_color.z();

    auto scale = 1.0 / sample_per_pixel;
    r = std::sqrt(scale * r);
    g = std::sqrt(scale * g);
    b = std::sqrt(scale * b);

    vec[i+0] = static_cast<unsigned char>(256 * clamp(r, 0.0, 0.999));
    vec[i+1] = static_cast<unsigned char>(256 * clamp(g, 0.0, 0.999));
    vec[i+2] = static_cast<unsigned char>(256 * clamp(b, 0.0, 0.999));
}

#endif // COLOR_H