Bresenham - CG Self Review

gistfile1.cpp

#include <cstdio>
#include <iostream>
#include <cmath>

using namespace std;

int sign(double x) {
    if (x < 0) return (-1);
    else return 1;
}

void Bresenham(int x0, int y0, int x1, int y1) {
     int dx, ax, sgnx, dy, ay, sgny, x, y, d;
     dx = x1 - x0;
     ax = abs(dx) * 2;
     sgnx = sign(dx);
     dy = y1 - y0;
     ay = abs(dy) * 2;
     sgny = sign(dy);
     
     x = x0;
     y = y0;
     
     if (ax > ay) {
         d = ay - ax/2;
         while (true) {
             cout << x << " " << y << endl;
             if (x == x1) break;
             if (d >= 0) {
                 y = y + sgny;
                 d = d - ax;                 
             }
             x = x + sgnx;
             d = d + ay;             
         }    
     }
     else {
         d = ax - ay/2;
         while (true) {
             cout << x << " " << y << endl;
             if (y == y1) break;
             if (d >= 0) {
                 x = x + sgnx;
                 d = d - ay;                 
             }
             y = y + sgny;
             d = d + ax;             
         }
     }
}

int main() {
    Bresenham(3, 4, 7, 10);   
}