igel / signals.elm

A toy project to learn Elm, describing German railway signals

Signals!

This is a toy project to learn Elm. It renders some German railway signals as SVG, because I wanted to learn them as well.

Setup

To be written 😱

Usage in your own project

The project is still being developed, so it can't yet be used from JavaScript directly. But you can use the signals from Elm.

Initialize a any kind of signal, call one of the initializers:

SignalModel.distantSignal : SignalModel.Model
SignalModel.signalRepeater : SignalModel.Model
SignalModel.combinationSignal : SignalModel.Model
SignalModel.mainSignal : SignalModel.Model

-- distant signal, a repeater, a combination signal and a main signal in a record
signals = { distantSignal = SignalModel.distantSignal
          , signalRepeater = SignalModel.signalRepeater
          , combinationSignal = SignalModel.combinationSignal
          , mainSignal = SignalModel.mainSignal
          }

Any of those signals can be displayed with calling

Signal.view : SignalModel.Model -> SignalModel.SignalType -> Svg msg

-- for example:
Signal.view signals.distantSignal SignalModel.Ks

For setting an aspect of the signal or configure certain things, have a look at the available messages in src/Messages.elm. Because the combination signal has both a distant as well main state, you have to tell the update function, which one you want to update (also for the distant or main signals).

Send the all messages both to the main signal and all corresponding distant signals. This way they will show the correct distant aspect for the main signal.

Signal.update : Messages.Target -> SignalModel.Model -> SignalModel.Model

-- for example:
signals =
    { signals
        | combinationSignal =
            Signal.update
                (ToDistantSignal (SetAspect Proceed))
                signals.combinationSignal
        , mainSignal =
            Signal.update
                (ToMainSignal (SetSpeedLimit (Just 4)))
                signals.mainSignal
    }