Function round

NULLC/includes/canvas.cpp:69–69

	void swap(int &a, int &b){ int tmp = a; a = b; b = tmp; }

	int round(double x){ return int(x + 0.5); }
	void swap(double &a, double &b){ double tmp = a; a = b; b = tmp; }
	double abs(double x){ return x < 0.0 ? -x : x; }
	double fpart(double x){ return x - floor(x); }