private void addTerrain(Terrain t) {

		int imax = 0;
		int disp = 0;
		switch (t) {
		case PLAINE:
			imax = 0;
			disp = 0;
			break;
		case FORET:
			imax = 5;
			disp = 3;
			break;
		case DESERT:
			imax = 3;
			disp = 2;
			break;
		case MONTAGNE:
			imax = 3;
			disp = 1;
			break;
		case VILLE:
			imax = 3;
			disp = 0;
			break;
		default:
			break;
		}

		int n = islandGraph.getVertices().size() - 1;
		for (int i = 0; i < imax; i++) {
			int randVertixId = (int) (n * Math.random());
			expand((Area) (islandGraph.getVertices().get(randVertixId + 1)),
					disp, t);
		}
	}