Langton's ant for openFrameworks.

Langton's ant - main.cpp

#include "ofMain.h"
#include "testApp.h"

//========================================================================
int main( ){
    ofSetupOpenGL(1280,720,OF_WINDOW);
    ofRunApp(new testApp());
}

Langton's ant - testApp.cpp

#include "testApp.h"

//--------------------------------------------------------------
void testApp::setup(){
    ofBackground(0, 0, 0);
    ofSetFrameRate(60);
    
    myImage.allocate(WIDTH, HEIGHT, OF_IMAGE_GRAYSCALE);
    pixels = myImage.getPixels();
    for (int i = 0; i < WIDTH * HEIGHT; i++) {
        pixels[i] = 0;
    }
    myImage.update();
    
    dirs[0].set(-1, 0); // left
    dirs[1].set(0, 1);  // top
    dirs[2].set(1, 0);  // right
    dirs[3].set(0, -1); // bottom
    
    for (int i = 0; i < ANTS_NUM; i++) {
        ants[i].row = int(ofRandom(WIDTH));
        ants[i].col =int(ofRandom(HEIGHT));
    }
}

//--------------------------------------------------------------
void testApp::update(){
    for (int i = 0; i < ANTS_NUM; i++) {
        for (int j = 0; j < ANTS_SPEED; j++) {
            if(field[ants[i].row][ants[i].col] == 1){
                ants[i].dir--;
            } else {
                ants[i].dir++;
            }
            if(field[ants[i].row][ants[i].col] == 1){
                field[ants[i].row][ants[i].col] = 0;
                pixels[ants[i].col * WIDTH + ants[i].row] = 0;
            } else {
                field[ants[i].row][ants[i].col] = 1;
                pixels[ants[i].col * WIDTH + ants[i].row] = 255;
            }
            ants[i].dir = (ants[i].dir + 4) % 4;
            ants[i].row += dirs[ants[i].dir].row;
            ants[i].col += dirs[ants[i].dir].col;
            ants[i].row = (ants[i].row + WIDTH) % WIDTH;
            ants[i].col = (ants[i].col + HEIGHT) % HEIGHT;
        }
    }
    myImage.update();
}

//--------------------------------------------------------------
void testApp::draw(){
    ofSetColor(0, 0, 255);
    ofSetRectMode(OF_RECTMODE_CORNER);
    myImage.draw(0, 0);
    ofSetColor(255, 0, 0);
    ofSetRectMode(OF_RECTMODE_CENTER);
    for (int i = 0; i < ANTS_NUM; i++) {
        ofRect(ants[i].row, ants[i].col, 4, 4);
    }
}

//--------------------------------------------------------------
void testApp::keyPressed(int key){
    
}

//--------------------------------------------------------------
void testApp::keyReleased(int key){
    
}

//--------------------------------------------------------------
void testApp::mouseMoved(int x, int y ){
    
}

//--------------------------------------------------------------
void testApp::mouseDragged(int x, int y, int button){
    
}

//--------------------------------------------------------------
void testApp::mousePressed(int x, int y, int button){
    
}

//--------------------------------------------------------------
void testApp::mouseReleased(int x, int y, int button){

}

//--------------------------------------------------------------
void testApp::windowResized(int w, int h){
    
}

//--------------------------------------------------------------
void testApp::gotMessage(ofMessage msg){
    
}

//--------------------------------------------------------------
void testApp::dragEvent(ofDragInfo dragInfo){
    
}

Langton's ant - testApp.h

#pragma once
#include "ofMain.h"

class Dir {
public:
    int row;
    int col;

    void set(int _row, int _col){
        row = _row;
        col = _col;
    }
};

class Ant {
public:
    int row;
    int col;
    int dir;

    Ant(){
        dir = int(ofRandom(4));
    }
};

class testApp : public ofBaseApp{
    
public:
    void setup();
    void update();
    void draw();
    
    void keyPressed(int key);
    void keyReleased(int key);
    void mouseMoved(int x, int y );
    void mouseDragged(int x, int y, int button);
    void mousePressed(int x, int y, int button);
    void mouseReleased(int x, int y, int button);
    void windowResized(int w, int h);
    void dragEvent(ofDragInfo dragInfo);
    void gotMessage(ofMessage msg);
    
    static const int WIDTH = 1280;
    static const int HEIGHT = 720;
    int field[WIDTH][HEIGHT] = { [0 ... WIDTH-1] = { [ 0 ... HEIGHT-1] = 0 } };;
    
    static const int ANTS_SPEED = 20;
    static const int ANTS_NUM = 50;
    Ant ants[ANTS_NUM];
    Dir dirs[4];
    
    ofImage myImage;
    unsigned char * pixels;
};