[podypodpod]

Im making a simple collision detection game, using a circle as the users charicter
I need to find the edges of the circle rather than the center point for collision
I've been presuming i need to make an object of an oval so i can the .getBounds and see if it intersects
something like this which i found online

                Rectangle r1 = rect1.getBounds();
                Rectangle r2 = rect2.getBounds();
 
                if (r1.intersects(r2))
                        collision = true;
                else
                        collision = false;

but im not quite sure how to go about making an oval object for starters (do i need to make my own class for this?), im sorry if i havent explained it too well as im fairly new with java.
Thanks

[macosxnerd101]

Take a look at using an Ellipse2D object.

[pbl]

Rectangle r1 = rect1.getBounds();
Rectangle r2 = rect2.getBounds();

if (r1.intersects(r2))
        collision = true;
else
        collision = false;

why not simply ?

collision = rect1.intersects(rect2);

When coding: KISS

[cfoley]

getBounds() will return the smallest rectangle that encompasses the shape so by using the strategy you describe above, you will be treating everything as a rectangle for the purposes of collision detection.

This might be OK for your purposes but if it is not, I would consider a different strategy.

To see if a rectangle is colliding with another, the above strategy is perfect.

If you are testing two circles, see if you can make something work with Pythagoras equations.

The tricky case is testing if a circle is intersecting a rectangle. It can be easily broken down by checking if the circle is intersecting any of the lines (or is wholly contained within the rectangle).

[CasiOo]

You can simply calculate the distance between the two circles center and subtract their radius

[Duta]

CasiOo, on 21 June 2012 - 07:47 AM, said:

You can simply calculate the distance between the two circles center and subtract their radius

That only works if they are both circular - if they are ovals, their radius isn't constant

[cfoley]

That's true but the OP says he is working with circles.