MatrixWalk.MatrixRotatingWalk.FillAllFreeCells C# (CSharp) Method

        private void FillAllFreeCells()
        {
            int directionRow = 1;
            int directionCol = 1;
            int number = 1;

            while (true)
            {
                this.matrix[this.row, this.col] = number;

                if (!this.IsCellAvailable(this.row, this.col))
                {
                    this.FindAllFreeCell();
                    if (this.IsCellAvailable(this.row, this.col))
                    {
                        number++;
                        this.matrix[this.row, this.col] = number;
                        directionRow = 1;
                        directionCol = 1;
                    }
                    else
                    {
                        break;
                    }
                }

                int nextRow = this.row + directionRow;
                int nextCol = this.col + directionCol;

                if (!this.IsInRange(nextRow) || !this.IsInRange(nextCol) || this.matrix[nextRow, nextCol] != 0)
                {
                    while (!this.IsInRange(nextRow) || !this.IsInRange(nextCol) || this.matrix[nextRow, nextCol] != 0)
                    {
                        this.GetNewDirection(ref directionRow, ref directionCol);

                        nextRow = this.row + directionRow;
                        nextCol = this.col + directionCol;
                    }
                }

                this.row = nextRow;
                this.col = nextCol;
                number++;
            }
        }