Inside the companion

First Light

Make your first CPU image, rasterize triangles, and trace an allocation budget.

Project files 15

Give an image one owner

Owned pixel storage and the renderer and PPM-writing interfaces.

#pragma once
#include "prism/scene.hpp"
#include <span>
#include <filesystem>

namespace prism {

// A value owns the complete RGB image. A span is only a temporary borrowed view.
struct Image {
    std::uint32_t width{}, height{};
    std::vector<std::uint8_t> rgb;
    [[nodiscard]] std::span<const std::uint8_t> pixels() const & noexcept { return rgb; }
    std::span<const std::uint8_t> pixels() const && = delete;
};

[[nodiscard]] std::expected<Image, Error> render(const Scene& scene);
[[nodiscard]] std::expected<void, Error> write_ppm(const std::filesystem::path& path,
                                                    const Image& image);
} // namespace prism

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