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/*
* simulation.cpp
*
* (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
*/
#include <ImageMagick-7/Magick++.h>
#include <string>
#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <cmath>
#include <getopt.h>
class v {
double _data[2];
public:
v(double x, double y) {
_data[0] = x;
_data[1] = y;
}
v() {
_data[0] = 0;
_data[1] = 0;
}
double& operator[](int i) { return _data[i]; }
const double& operator[](int i) const { return _data[i]; }
v operator+(const v& other) const {
v result;
result[0] = _data[0] + other[0];
result[1] = _data[1] + other[1];
return result;
}
v operator-(const v& other) const {
v result;
result[0] = _data[0] - other[0];
result[1] = _data[1] - other[1];
return result;
}
v operator*(double l) const {
v result;
result[0] = l * _data[0];
result[1] = l * _data[1];
return result;
}
Magick::Coordinate coordinate() {
return Magick::Coordinate(_data[0], _data[1]);
}
};
v f(const v& x) {
v result;
result[0] = -x[1];
result[1] = x[0];
return result;
}
v rkstep(const v& x, double h) {
v k1 = f(x);
v k2 = f(x + k1 * (h/2));
v k3 = f(x + k2 * (h/2));
v k4 = f(x + k3 * h);
return x + (k1 + k2 * 2 + k3 * 2 + k4) * (h/6);
}
v rotation(const v& x0, int steps) {
double h = 2 * M_PI / steps;
v x = x0;
for (int i = 0; i < steps; i++) {
x = rkstep(x, h);
}
return x;
}
v rotations(const v& x0, int rot, int steps) {
v x = x0;
for (int i = 0; i < rot; i++) {
x = rotation(x, steps);
}
return x;
}
struct option longoptions[] = {
{ "width", required_argument, NULL, 'w' },
{ "height", required_argument, NULL, 'h' },
{ "scale", required_argument, NULL, 'S' },
{ "steps", required_argument, NULL, 's' },
{ "rotations", required_argument, NULL, 'r' },
{ "iterations", required_argument, NULL, 'i' },
{ NULL, 0, NULL, 0 }
};
int main(int argc, char *argv[]) {
Magick::InitializeMagick(*argv);
int width = 1920;
int height = 1080;
double scale = 500;
int steps = 80;
int nrotations = 40000;
int iterations = 200;
int c;
int longindex;
std::string outputpath;
while (EOF != (c = getopt_long(argc, argv, "w:h:S:s:r:i:", longoptions, &longindex)))
switch (c) {
case 'w':
width = std::stoi(optarg);
break;
case 'h':
height = std::stoi(optarg);
break;
case 'S':
scale = std::stod(optarg);
break;
case 's':
steps = std::stoi(optarg);
break;
case 'r':
nrotations = std::stoi(optarg);
break;
case 'i':
iterations = std::stoi(optarg);
break;
}
if (optind < argc) {
outputpath = std::string(argv[optind++]);
}
Magick::Geometry geometry(width, height);
std::string backgroundcolorspec("white");
std::string axescolorspec("black");
std::string curvecolorspec("red");
Magick::ColorRGB background(backgroundcolorspec);
Magick::ColorRGB axescolor(axescolorspec);
Magick::ColorRGB curvecolor(curvecolorspec);
Magick::ColorRGB transparent("transparent");
Magick::Image image(geometry, background);
image.strokeColor(axescolor);
// draw axes
std::vector<Magick::Drawable> objects_to_draw;
objects_to_draw.push_back(Magick::DrawableStrokeWidth(5));
objects_to_draw.push_back(Magick::DrawableLine(0,540, 1919, 540));
objects_to_draw.push_back(Magick::DrawableLine(960,0,960,1079));
image.draw(objects_to_draw);
// compute rotations and errors an plot the errors
v x0(1,0);
v x = x0;
v offset(980, 540);
image.strokeColor(curvecolor);
Magick::CoordinateList path;
path.push_back((x - x0 + offset).coordinate());
for (int n = 0; n < iterations; n++) {
//v from = (x - x0) * 100;
x = rotations(x, nrotations, steps);
v to = (x - x0) * scale + offset;
std::cout << "(" << to[0] << "," << to[1] << ")" << std::endl;
path.push_back(to.coordinate());
std::vector<Magick::Drawable> segments;
segments.push_back(Magick::DrawableFillColor(transparent));
segments.push_back(Magick::DrawableStrokeWidth(5));
segments.push_back(Magick::DrawablePolyline(path));
image.draw(segments);
// write the image if the output path is set
if (outputpath.size() > 0) {
char buffer[1024];
snprintf(buffer, sizeof(buffer), "%s%05d.jpg",
outputpath.c_str(), n);
image.write(buffer);
}
}
// write the image
image.write("test.jpg");
}
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