Canvas EFIS framework: Difference between revisions

{{Template:Canvas Navigation}}

* If an animation is triggered only by one property and that property is unlikely to change often, remove the prop / animation from the update loop and use a listener instead. The listener may read other props as needed. A listener does not consume any CPU unless the property it listens to has changed, in which case the listener function is run.

This is the top level class which ties together the different parts like display units, sources and cockpit controls.  

{{Nasal doc

|syntax = new(display_names, object_names, canvas_settings=nil);

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{{Nasal doc

|syntax = setPowerProp(path);

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{{Nasal doc

|syntax = setWindowSize(window_size);

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{{Nasal doc

|syntax = setDUPowerProps(power_props, minimum_power=0);

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{{Nasal doc

|syntax = addSource(efis_canvas);

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{{Nasal doc

|syntax = addDisplaySwapControl(ctrl, mappings, callback=nil);

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{{Nasal doc

|syntax = addSourceSelector(selected, target, sources=nil);

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{{Nasal doc

|syntax = setDefaultMapping(mapping);

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{{Nasal doc

|syntax = displayWindow(id);

EFISCanvas manages a single canvas for you.  

It offers a bunch of little helpers to make the live of an aircraft developer easier.  

These helpers mostly do animation and update stuff on canvas elements in an efficient way.

{{Nasal doc

|syntax = new(name, svgfile);

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returns path of canvas

returns canvas instance

returns root group of the canvas

{{Nasal doc

|syntax = setUpdateN(node);

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{{Nasal doc

|syntax = loadsvg(file);

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{{Nasal doc

|syntax = addUpdateFunction(f, interval);

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Start all update timers.

Stop all update timers.

When updating EFIS displays, there is a need to access properties under /instrumentation very often.

To avoid the rather expensive append operator ("~") and property path lookups, you should use this little helper.

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{{Nasal doc

|syntax = updateTextElement(svgkey, text, color=nil);

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private function that sets clipping for an element, if there is another element with the same name extended by "_clip".

{{note|

The following listener factories will return a function. The general usage is  

{{Nasal doc

|syntax = _makeListener_showHide(svgkey, value=nil);

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{{Nasal doc

|syntax = _makeListener_rotate(svgkey, factors=nil);

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{{Nasal doc

|syntax = _makeListener_translate(svgkey, fx, fy);

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{{Nasal doc

|syntax = _makeListener_setColor(svgkey, color_true, color_false);

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{{Nasal doc

|syntax = _makeListener_updateText(svgkey, format="%s", default="");

This class is used by the EFIS class. DisplayUnit creates and places a canvas to a 3D object specified in new().

{{Nasal doc

|syntax = new(name, canvas_settings, screen_obj, parent_obj = nil);

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{{Nasal doc

|syntax = display_unit.setSource(path);

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{{Nasal doc

|syntax = display_unit.setPowerSource(prop, min);

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{{Nasal doc

|syntax = display_unit.asWindow(window_size);

The message system decouples the update of canvas text elements (e.g. message lines) from the handling of messages.

It is configured with the necessary message classes (e.g. warnings, caution messages, status messages) and a list of all possible messages.

Alternatively, a message can be shown or hidden via the Nasal methods (see also the HOWTO section for examples and best practices).

{{Nasal doc

|syntax = new(page_length, prop_path);

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{{Nasal doc

|syntax = setPowerProp(prop_path);

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{{Nasal doc

|syntax = addMessageClass(class_name, paging, color = nil);

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{{Nasal doc

|syntax = addMessages(class, messages);

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{{Nasal doc

|syntax = addAuralAlerts(alert_hash);

|text = Set aural alert configuration hash

|param1 = alert_hash

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{{Nasal doc

|syntax = setMessage(class, msg_id, visible=1);

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{{Nasal doc

|syntax = init();

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{{Nasal doc

|syntax = hasUpdate();

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{{Nasal doc

|syntax = setPageLength(length);

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{{Nasal doc

|syntax = getPageLength();

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{{Nasal doc

|syntax = getFirstUpdateIndex();

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{{Nasal doc

|syntax = getActiveMessages();

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{{Nasal doc

|syntax = getMessageID(class, msg_text);

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{{Nasal doc

|syntax = disableMessage(class, msg_id);

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{{Nasal doc

|syntax = enableMessage(class, msg_id);

'''-- following methods are for message output on a canvas --'''

{{Nasal doc

|syntax = setCanvasGroup(group);

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{{Nasal doc

|syntax = createCanvasTextLines(left, top, line_spacing, font_size);

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{{Nasal doc

|syntax = createPageIndicator(left, top, font_size, format_string = nil);

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{{Nasal doc

|syntax = updateCanvas();

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{{Nasal doc

|syntax = updatePageIndicator(current, total);

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MessageSystem.addMessages() expects a vector of message definitions. A message definition is a hash with the keys ''msg'', ''prop'', ''aural'', ''condition'' (only msg is required, the rest is optional).

The optional ''aural'' element can be any key of the aural configuration hash passed to MessageSystem.addAuralAlerts(). If the  

{

     msg: "Message Text",

var EICASMessages = [

     {msg: "APU FIRE", prop: "engines/engine[2]/on-fire", aural: "firebell"},

     {msg: "ELT ON", prop: ""},

];

Helper class for MessageSystem. Stores configuration data for a message class.

Helper class for MessageSystem.

The pager class takes a vector of messages and splits it into pages (sub vectors of defined length).

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{{Nasal doc

|syntax = new(page_length, prop_path);

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{{Nasal doc

|syntax = page(lines);

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{{Nasal doc

|syntax = pageChanged();

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{{Nasal doc

|syntax = setPageLength(lines);

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{{Nasal doc

|syntax = setPage(page);

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Returns total number of pages, according to last run of page()

Returns current page, according to last run of page()

== HOWTO and Examples ==

to be written / reference implementation in CRJ700 familiy to be published after framework is published.