// Returns vertical component of combo position in screen grid.
int GetComboRank (int cmb){
	return (ComboY (cmb)/16);
}

// Returns horizontal component of combo position in screen grid.
int GetComboFile (int cmb){
	return (ComboX (cmb))/16;
}

// Returns TRUE, if two given combos are on same horizontal row.
bool OnSameRank(int cmb1, int cmb2){
	int r1 = ComboY (cmb1);
	int r2 = ComboY (cmb2);
	return r1==r2;
}

// Returns TRUE, if two given combos are on same vertical column.
bool OnSameFile(int cmb1, int cmb2){
	int r1 = ComboX (cmb1);
	int r2 = ComboX (cmb2);
	return r1==r2;
}

// Returns TRUE, if two given combos are on same diagonal.
bool OnSameDiagonal(int cmb1, int cmb2){
	int r1 = ComboY (cmb1);
	int r2 = ComboY (cmb2);
	int f1 = ComboX (cmb1);
	int f2 = ComboX (cmb2);
	return (Abs (r1-r2) == Abs (f1-f2));
}

// Returns TRUE, if two given combos are within move of leaping chess piece.
bool LeaperMoveAdjacent(int cmb1, int cmb2, int l1, int l2){
	int r1 = ComboY (cmb1);
	int r2 = ComboY (cmb2);
	int f1 = ComboX (cmb1);
	int f2 = ComboX (cmb2);
	if ((Abs(r1-r2)/16)==l1){
		if ((Abs(f1-f2)/16)==l2) return true;
	}
	if ((Abs(r1-r2)/16)==l2){
		if ((Abs(f1-f2)/16)==l1) return true;
	}
	return false;
}

//Shorthand for knight move.
bool KnightMoveAdjacent(int cmb1, int cmb2){
	return LeaperMoveAdjacent(cmb1, cmb2, 1, 2);
}

//test script. Paints all combos within knight move of FFC`s position.
ffc script chtest{
	void run(){
		int cmb = ComboAt (this->X, this->Y);
		for (int i = 0; i<176; i++){
			if (LeaperMoveAdjacent(cmb,i, 0,1 )) Screen->ComboC[i]=7;;
		}
	}
}