Creating Object2dDisplay
Purpose: To catch mouse-clicks on raster and open probe to agent at this grid square
Note that we need to define both Discrete2d, List, method to display agents and method to display probe
worldDisplay = [Object2dDisplay createBegin: self];
[worldDisplay setDisplayWidget: worldRaster];
[worldDisplay setDiscrete2dToDisplay: [modelSwarm getWorld]];
[worldDisplay setObjectCollection: [modelSwarm getPlayers]];
[worldDisplay setDisplayMessage: M(drawSelfOn:)];
worldDisplay = [worldDisplay createEnd];
[worldRaster setButton: ButtonRight Client: worldDisplay Message: M(makeProbeAtX:Y:)];