initial import, >900commits predate this

docs/framework/screen_director/screen_director.md

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+# Screen Director
+
+Orchistrates `Screen`s.
+
+The `Screen Director` lets you define "States"(`Screen`s) which activate/deactivate `MM::Service`s on Entering and Leaving the `Screen`.
+
+# Usage
+
+The current implementation is very open and does not really use encapsulation ...
+
+## Adding `Screen`s
+
+Due to the open nature of this implementation, one does access members directly:
+```
+auto& my_screen = screen_director.screens["my_screen"];
+
+// filling in start_disable, start_enable, start_provide, end_disable and end_enable
+// and optionally start_fn and end_fn which are called upon entering and leaving the screen.
+my_screen.start_enable.push_back(engine.type<MyService>());
+// [...]
+```
+
+## Changing to a Screen
+
+Changing to a `Screen` can either be done on call with `.changeScreenTo(engine, "my_screen_id")` or qued via `.queueChangeScreenTo("my_screen")`. The former should only be used when the `Engine` is not running or in a `fixedDeferUpdate`.
+
+## Service Enablement
+
+Enabling the ScreenDirector causes a queued `Screen` to be started.
+
+