Merge pull request #3 from bell07/master

Some documentation

API.md

@@ -0,0 +1,32 @@
+# Laptop Mod API
+
+## Node creator helpers
+- `laptop.os_get(pos)` - Get an OS object. Usefull in on_construct or on_punch to initialize or do anything with OS
+  Needed in on_receive_fields to be able to call os:receive_fields(fields, sender) for interactive apps
+- `laptop.after_place_node` / `laptop.after_dig_node` - (optional) can be used directly for node definition. Move laptop apps data to ItemStack if digged and restored back if placed again. So you can take along your laptop. Note: you need to set `stack_max = 1` because the data can be stored per stack only, not per item.
+
+
+## Operating system calls
+Usable from node functions, from apps or outsite
+
+`local os = laptop.os_get(pos)` - Get the Operating system object. pos is the node position
+
+- `os:power_on(new_node_name)` - Activate the app "launcher" and if given swap node to new_node_name
+- `os:power_off(new_node_name)` - Remove the formspec and if given swap node to new_node_name
+- `os:set_infotext(infotext)` - Set the mouseover infotext for laptop node
+- `os:save()` - Store all app-data to nodemeta. Called mostly internally so no explicit call necessary
+- `os:set_app(appname)` - Start/Enable/navigate to appname. If no appname given the launcher is called
+- `os:receive_fields(fields, sender)` - Should be called from node.on_receive_fields to get the apps interactive
+
+
+## App Definition
+`laptop.register_app(internal_shortname, { definitiontable })` - add a new app or view
+- `app_name` - App name shown in launcher. If not defined the app is just a view, not visible in launcher but can be activated. This way multi-screen apps are possible
+- `background_img` - if set the image is added as background to formspec by framework
+-	`formspec_func(app, os)` - Function, should return the app formspec (mandatory) During definition the "app" and the "os" are available
+-	`receive_fields_func(app, os, fields, sender)` Function for input processing. The "app" and the "os" are available inside the call
+
+## App Object
+`local app = laptop.get_app(internal_shortname, os)` - Give the app object internal_shortname, connected to given os. Not necessary in formspec_func or receive_fields_func because given trough interface
+- `data = app:get_storage_ref()` - Returns a "persitant" data table that means the data in this table is not lost between formspec_func, receive_fields_func, apps-switch or on/off.
+- `app.background_img` - Background image from definition. Can be changed at runtime