I made a new editor with some of the suggestions posted, I still need to add enemies and spawn points to the editor and then hopefully I will be able to create something playable. I guess the approach I will take will be to have 2 layers. The first one for the map which is currently just:

int tileMap[20][10];

and the next one will be for enemies which will be:

int enemyMap[20][10];

it will scroll at the same pace as the tileMap.



You can try it here.

The code can be downloaded here.

A demo of what I have so far can be found here. Controls are arrows keys for movement and space bar to shoot.

This is what it looks like: