hacklebrot

mandelbrot.cpp

#include <string>
#include <iostream>
#include <fstream>
#include <cmath>
#include <complex>
#include <algorithm>


int main(int argc, std::string argv[]) {
	if (argc != 8) {
		std::cout << "help: mandelbrot <iterations> <left x> <x step> <right x> <bottom y> <y step> <top y>" << "\n";
		std::cout << std::to_string(argc) << "\n";
		exit(1);
	}
	long double xLeft = std::stold(argv[2]);
	long double xStep = std::stold(argv[3]);
	long double xRight = std::stold(argv[4]);
	long double yBottom = std::stold(argv[5]);
	long double yStep = std::stold(argv[6]);
	long double yTop = std::stold(argv[7]);
	long xPixels = (long)std::floor((xRight - xLeft) / xStep);
	long yPixels = (long)std::floor((yTop - yBottom) / yStep);
	int iterations = std::stoi(argv[1]);
	int maxDepth = iterations;
	std::vector<int> mandelVector;
	long iter;
	for (long double imaginary = yTop; imaginary > yBottom; imaginary -= yStep) {
		for (long double real = xLeft; real < xRight - (xStep/2); real += xStep) { //FIX THIS xRight - (xStep/2) PLEASE IT'S SO BROKEN IT'S JUST TO COMPENSATE FOR FLOATING POINT ERRORS
			std::complex<long double> lastComplex = std::complex<long double>(0.0, 0.0);
			std::complex<long double> thisComplex = std::complex<long double>(real, imaginary);
			std::complex<long double> coordComplex = thisComplex;
			std::complex<long double> tempComplex;
			for (iter = 0; iter < iterations; iter++) {
				tempComplex = thisComplex;
				thisComplex = lastComplex * lastComplex + coordComplex;
				lastComplex = tempComplex;
				if (std::abs(thisComplex) >= 2) {
					break;
				}
			}
			mandelVector.push_back(iter);
		}
	}

	std::string mandelStringHeader = "P2\n" + std::to_string(xPixels) + " " + std::to_string(yPixels) + "\n" + std::to_string(maxDepth) + "\n";
	std::string mandelString = "";
	for (auto pix : mandelVector) {
		mandelString += std::to_string((int)std::floor(pix)) + " ";
	}
	mandelString = mandelStringHeader + mandelString;
	std::ofstream mandelImage;
	mandelImage.open("mcplusplus.pgm");
	mandelImage << mandelString;
	mandelImage.close();
}