fgdata/Nasal/canvas/generic-canvas-map.xml

<?xml version="1.0"?>
<!--
 generic-canvas.map XML: 
	- to be used by dialogs and instruments to add a generic map (navaids, fixes, airports etc)
	- with each feature put on a separate layer (canvas group)
	- each layer being controllable via a boolean property
	
NOTE: This is still work in progress, and will be significantly refactored in the time to come

Current requirements: (these are subject to change)

Dialogs wanting to use this, MUST:

	- set DIALOG_CANVAS in open block
	- provide a helper function dialog_property(p) to return a property appended to the dialog root in /sim/gui/dialogs/FOO/ 
	- to set up layer-checkboxes automatically, use canvas.GenericMap.setupGUICheckboxes(DIALOG_CANVAS, gui_group)

For example, add this to your dialogs Nasal/open block in "foo.xml":
	var dialog_name = "foo";
	var dialog_property = func(p) return "/sim/gui/dialogs/foo/"~p; 	
	var DIALOG_CANVAS = gui.findElementByName(cmdarg(), "airport-selection"); 
	canvas.GenericMap.setupGUICheckboxes(DIALOG_CANVAS, "canvas-control");

TODO: use a single "InitCanvasMapSupport();" helper

In the close block, you'll want to call "map.cleanup_listeners()" at the moment

-->
<PropertyList>
	<!--FIXME: move somewhere else, this is GUI specific and not useful for canvas maps shown as instruments! -->
	<checkbox-toggle-template>
              <name></name>
              <label></label>
              <property></property>
              <binding>
                <command>dialog-apply</command>
                <object-name></object-name>
              </binding>
        </checkbox-toggle-template>

	<!-- will be procedurally added to the dialog -->
	<zoom-template>
          <button>
              <name>zoomout</name>
              <legend>-</legend>
              <pref-width>22</pref-width>
              <pref-height>22</pref-height>

              <binding>
                  <command>property-adjust</command>
                  <property></property>
                  <min>0</min>
                  <step>-1</step>
              </binding>
          </button>

          <text>
              <label>MMMM</label>
              <halign>center</halign>
              <format>Zoom %d</format>
              <property></property>
              <live>true</live>
          </text>

	<button>
              <name>zoomin</name>
              <legend>+</legend>
              <pref-width>22</pref-width>
              <pref-height>22</pref-height>

              <binding>
                  <command>property-adjust</command>
                  <property></property>
                  <step>1</step>
                  <max></max> <!-- FIXME: compute dynamically via Nasal size() or just a property-->
              </binding>
          </button>

          <empty><stretch>true</stretch></empty>
	
	</zoom-template>

        <nasal>      
        <load><![CDATA[
          var my_canvas = canvas.get(cmdarg());
          my_canvas.setColorBackground(0.2, 0.5, 0.2, 0.5); #TODO: support customization in XML

          var root = my_canvas.createGroup();
	  # the top level AirportMap element uses a "GenericMap" now:

	  #TODO: features should be procedurally enabled via params (WIP)
	  #TODO: use generic Map and instantiate via XML
          var map = canvas.GenericMap.new(parent:root, name:dialog_name) 	# FIXME: We shouldn't be using AirportMap here:
										# we need a high level wrapper that can instantiate
										# all sorts of maps, not just AirportMaps
                        .setTranslation(300, 200) # TODO: move to Map class ctor!
			.setupZoom( dialog:DIALOG_CANVAS ) 			# TODO: make zooming configurable for non GUI use
			.pickupFeatures (DIALOG_CANVAS);			# set up the features specified in the XML file

	  var offset = [0,0];
	  my_canvas.addEventListener("drag", func(e)
          {
            offset[0] += e.deltaX;
            offset[1] += e.deltaY;
            map.setTranslation(300 + offset[0], 200 + offset[1]);
          });

          my_canvas.addEventListener("wheel", func(e)
          {
            map.zoom_property.setIntValue(map.zoom_property.getValue() + e.deltaY );
          });

	canvas.run_callbacks(); # WORKAROUND to run dialog-specific init code - 
				# must be set up via register_callback() in the dialog's open block currently 
          ]]>
          </load>
        </nasal>
</PropertyList>