gridded an irregular area in matlab

Dear All..

I have a problem with my final project about matlab. Those problem are :
1. How can i divide an irregular area into a small blocks (grid) ? Please, can anyone give me a code? Before, i built the irregular area by connected point to point coordinates of the X an Y axis.
2. That code can work when we input a size of the grid, so it's automatically generated by the size that we given.
3. Everyone, please help me. The date of my deadline already close enough.

below, i attach a map figure of irregular area that i mean above.
i'm very thankful for your help.

sincerely,
Allice Ellisa