Stringgrid

[Barbara]

Hi everybody

I have a stringgrid that represents a chess board. I need to place a Q (this represents the queen in chess) on the board randomly.  This part I can do.  The problem is the following -
After the Q is placed randomly I need to click on another button and show the possible moves.  From where the Q is placed on the stringgrid I need to place a  star (*) in each cell, vertically, horizontally and diagonally from where the Q is placed to show the posible moves, this I do not know how to do.  

Please can anyone help me with this code.

Thank you very much