default boolean discoverCenter() {
        IConnectable c = getCenter();
        if (c != null) {
            return canConnectPart(c, -1) && c.connectInternal(this, -1);
        }
        return false;
    }
Tries to locate a corner connectable part towards r and establish a connection.

@param r The rotation towards the external corner part
@return True if connection was established
core/src/main/java/mrtjp/projectred/core/part/IConnectableFacePart.java