+ Add a signal to the rail system. +
++ Add a segment boundary to the rail system. A segment boundary is a + point where a train can cross between two segments, or "blocks" in + the system. For example, a train may move from a junction segment to + a main line. This boundary is a place where a detector component can + update the system as trains pass. +
++ Add a label to the rail system as a piece of text on the map. Labels + are purely a visual component, and do not interact with the system + in any way, besides being a helpful point of reference for users. +
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