An app that toggles nodes on a map

[BipolarBear]

I have a gigantic map, with at least 1,300 nodes, similar to this

I have the app written to the point where I can fling and zoom in and out of a bitmap.(I used the onDraw() method).

However, obviously this won't work.. I don't need a bitmap with nodes on a strict x,y grid.


I need to simply, layout a giant jpeg, define thousands of nodes in an unorganized fashion, and have the ability to toggle them. Then simply increment and decrement the number of nodes as they are toggled.

My question is, what methods(both the literal definition and Java syntax definition) should I use to:
1. Lay out a map on the screen.
2. Define nodes on it.
3. Be able to toggle them. onTouchEvent() I presume

Any ideas or help would be very much appreciated.