Generate all 1000x1000 24 bit color images.

all_images.cc

#include <cstdint>

typedef std::size_t size_t;

template <typename color_t, typename Func>
void generate_images(size_t width, size_t height, size_t components, color_t limit, Func visit) {
	size_t image_size = width * height * components;
	color_t* image;
	size_t* focus;
	bool* direction;

	image = new color_t[image_size];
	focus = new size_t[image_size + 1];
	direction = new bool[image_size];

	for(size_t i = 0; i < image_size; i++) {
		image[i] = 0;
		direction[i] = true;
	}

	for(size_t i = 0; i <= image_size; i++) {
		focus[i] = i;
	}

	for(;;) {
		visit(width, height, components, image);

		size_t update = focus[0];
		focus[0] = 0;

		if(update >= image_size) {
			break;
		}

		image[update] += direction[update] ? 1 : -1;

		if(image[update] == 0 || image[update] == limit) {
			direction[update] = !direction[update];
			focus[update] = focus[update + 1];
			focus[update + 1] = update + 1;
		}
	}

	delete[] focus;
	delete[] image;
	delete [] direction;
}

int main() {
	typedef uint8_t color_t;
	size_t width = 1000;
	size_t height = 1000;
	size_t components = 3;
	generate_images<color_t>(width, height, components, ~0, [](size_t width, size_t height, size_t components, color_t* image) {
		/* TODO: Do something with the image. */
	});
	return 0;
}