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SFML projects / Function pointer plotter

« on: November 22, 2016, 04:00:18 pm »

I made a small function pointer plotter in SFML, thinking that someone might want to use it in some way. The code below contains the plot function and some usage examples:

#include <SFML/graphics.hpp>
#include <cmath>
#include <random>

using namespace std;

template <typename T1, typename T2>
void plot(T1 (*f)(T2), T2 begin, T2 last, T2 step, T1 yMin, T1 yMax, sf::Color plotColor, sf::Color axisColor, sf::RenderWindow& window) {
    T2 current = begin;
    if(axisColor != sf::Color::Transparent) {
        sf::RectangleShape xAxis, yAxis;
        xAxis.setSize(sf::Vector2f(window.getSize().x, 1));
        xAxis.setPosition(0, yMax/(yMax-yMin)*window.getSize().y);
        xAxis.setFillColor(axisColor);
        yAxis.setSize(sf::Vector2f(1, window.getSize().y));
        yAxis.setPosition((-begin)/(last-begin)*window.getSize().x, 0);
        yAxis.setFillColor(axisColor);
        window.draw(xAxis), window.draw(yAxis);
    }
    if(step == 0) return;
    sf::RectangleShape v(sf::Vector2f(1, 1));
    v.setFillColor(plotColor);
    for(; current <= last; current += step) {
        v.setPosition((float)(current-begin)/(last-begin)*window.getSize().x,
                                                (yMax-f(current))/(yMax-yMin)*window.getSize().y);
        window.draw(v);
    }
}

template <typename T1, typename T2>
void plot(vector <pair<T1 (*)(T2), sf::Color>> fs, T2 begin, T2 last, T2 step, T1 yMin, T1 yMax, sf::Color axisColor, sf::RenderWindow& window) {
    if(fs.size())
        plot(fs[0].first, begin, last, step, yMin, yMax, fs[0].second, axisColor,              window);
    for(int i = 1; i < fs.size(); ++ i)
        plot(fs[i].first, begin, last, step, yMin, yMax, fs[i].second, sf::Color::Transparent, window);
};

float timesort(int nElements) {
    sf::Clock clock;
    std::vector <int> elements(nElements);
    std::random_device dev;
    std::mt19937 mt (dev());
    std::uniform_int_distribution <int> dist(0, 1 << 30);
    for(auto &e: elements)
        e = dist(mt);
    clock.restart();
    std::sort(elements.begin(), elements.end());
    return clock.getElapsedTime().asSeconds();
}

int main() {
    sf::RenderWindow window(sf::VideoMode::getDesktopMode(), "Math Functions");
    redraw:
    window.clear(sf::Color::Black);
    plot((vector <pair<float (*)(float), sf::Color>>){
                 {&sin,    sf::Color::Green},
                 {&exp,    sf::Color::Blue},
                 {&tgamma, sf::Color::Magenta},
                 {&log,    sf::Color::Red}
         }, -3.0f, 5.0f, 0.0001f, -20.0f, 20.0f, sf::Color::White, window);
    window.display();
    while(window.isOpen()) {
        sf::sleep(sf::milliseconds(30));
        sf::Event event;
        while(window.pollEvent(event))
            switch(event.type) {
                case sf::Event::Resized:
                    window.setView(sf::View(sf::FloatRect(0, 0, event.size.width, event.size.height)));
                    goto redraw;
                case sf::Event::Closed:
                    window.close();
            }
    }

    sf::RenderWindow window2(sf::VideoMode::getDesktopMode(), "Vector sort times");
    redraw2:
    window2.clear(sf::Color::Black);
    plot(&timesort, 100, 100000, 100, .0f, 0.01f, sf::Color::Magenta, sf::Color::Transparent, window2);
    window2.display();
    while(window2.isOpen()) {
        sf::sleep(sf::milliseconds(30));
        sf::Event event;
        while(window2.pollEvent(event))
            switch(event.type) {
                case sf::Event::Resized:
                    window2.setView(sf::View(sf::FloatRect(0, 0, event.size.width, event.size.height)));
                    goto redraw2;
                case sf::Event::Closed:
                    window2.close();
            }
    }
    return 0;
}
 

Upon running the code, the first window gets created:
After closing that window, the second windows is created:
I hope someone can find some fun usages for this. As it can be used on many 1 dim -> 1 dim functions, you can use it to fine tune variables, debug, etc. I will try to keep up with the thread and see if anyone can make something cool with it.