public Case[][] getCopieCases(){
		int i,j;
		Case [][] newCases = new Case [this.nbX][this.nbY];
		for(i = 0; i < this.nbX; ++i){
			for(j = 0; j < this.nbY; ++j){
				newCases[i][j] = new Case(this.cases[i][j]);
			}
		}
		return newCases;
	}