Hi people,

I Have a problem. The game im making needs to have players on a oval in different positions and not go outside the confines of the oval. The view of the oval is from side on and 45 degrees up giving a nice view of the oval in a 3d perspective.
Im new to java, was going to make this game on XNA but hit a few stumbling blocks with the database i wanted to implement. So Ive invested some money in 2 java books and im reading  them at the moment (Java How to Program, 4th 2004. and Developing Games in JAVA).
 i just keep thinking how will i keep the players in the oval etc. i had a brief read of that section of the book and its saying 0,0 0,1 1,1 2,2 0,3 etc but i cant just say 4,4 is one boudry and 440,440 is another etc. i havent fully read it yet but i just cant get my head around how the coordinates will work with an oval. I uploaded a picture just to give you an idea of what im trying to do. i was thinking of doing the game 2d and having the players resize larger and smaller depending what side of the field they are on to make them look closer and far away. or should i go 3d? is it much harder? or just as simple as adding one more dimension? Its got me stumped so any help would be great thanks