from #33, distanceProperty moved to GFLBModel and instrumented for ph…

…etio, arrow node instrumented for phetio
phetsims · Jan 19, 2018 · 681b20a · 681b20a
1 parent cb0850c
commit 681b20a
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Showing 3 changed files with 27 additions and 8 deletions.
diff --git a/js/gravity-force-lab-basics/model/GravityForceLabBasicsModel.js b/js/gravity-force-lab-basics/model/GravityForceLabBasicsModel.js
@@ -10,12 +10,15 @@ define( function( require ) {
 
   // modules
   var Color = require( 'SCENERY/util/Color' );
+  var DerivedProperty = require( 'AXON/DerivedProperty' );
+  var DerivedPropertyIO = require( 'AXON/DerivedPropertyIO' );
   var gravityForceLabBasics = require( 'GRAVITY_FORCE_LAB_BASICS/gravityForceLabBasics' );
   var GravityForceLabBasicsConstants = require( 'GRAVITY_FORCE_LAB_BASICS/gravity-force-lab-basics/GravityForceLabBasicsConstants' );
   var inherit = require( 'PHET_CORE/inherit' );
   var ISLCConstants = require( 'INVERSE_SQUARE_LAW_COMMON/ISLCConstants' );
   var ISLCModel = require( 'INVERSE_SQUARE_LAW_COMMON/model/ISLCModel' );
   var Mass = require( 'INVERSE_SQUARE_LAW_COMMON/model/Mass' );
+  var NumberIO = require( 'ifphetio!PHET_IO/types/NumberIO' );
   var Property = require( 'AXON/Property' );
   var PropertyIO = require( 'AXON/PropertyIO' );
 
@@ -72,6 +75,17 @@ define( function( require ) {
       snapObjectsToNearest: GravityForceLabBasicsConstants.MASS_POSITION_DELTA,
       minSeparationBetweenObjects: 200 // in meters
     } );
+
+    // @public
+    this.distanceProperty = new DerivedProperty( [ 
+        this.object1.positionProperty, 
+        this.object2.positionProperty
+      ], function( x1, x2 ) {
+        return Math.abs( x2 - x1 ) / 1000;
+      }, {
+        phetioType: DerivedPropertyIO( NumberIO ),
+        tandem: tandem.createTandem( 'distanceProperty' )
+      } );
   }
 
   gravityForceLabBasics.register( 'GravityForceLabBasicsModel', GravityForceLabBasicsModel );

diff --git a/js/gravity-force-lab-basics/view/DistanceArrowNode.js b/js/gravity-force-lab-basics/view/DistanceArrowNode.js
@@ -18,6 +18,7 @@ define( function( require ) {
   var PhetFont = require( 'SCENERY_PHET/PhetFont' );
   var Property = require( 'AXON/Property' );
   var StringUtils = require( 'PHETCOMMON/util/StringUtils' );
+  var Tandem = require( 'TANDEM/Tandem' );
   var Text = require( 'SCENERY/nodes/Text' );
 
   // strings
@@ -28,17 +29,20 @@ define( function( require ) {
   var HEAD_HEIGHT = 6;
 
   /**
-   * @param {Property} mass1PositionProperty
-   * @param {Property} mass2PositionProperty
+   * @param {GravityForceLabBasicsModel} model
    * @param {ModelViewTransform2} modelViewTransform
    * @param {Object} options
    * @constructor
    */
-  function DistanceArrowNode( mass1PositionProperty, mass2PositionProperty, modelViewTransform, options ) {
+  function DistanceArrowNode( model, modelViewTransform, options ) {
+
+    _.extend( {
+      tandem: Tandem.required
+    }, options );
 
     Node.call( this, options );
 
-    var arrowNode = new ArrowNode( mass1PositionProperty.get(), 0, mass2PositionProperty.get(), 0, {
+    var arrowNode = new ArrowNode( model.object1.positionProperty.get(), 0, model.object2.positionProperty.get(), 0, {
       doubleHead: true,
       tailWidth: 0.5,
       headHeight: HEAD_HEIGHT,
@@ -51,19 +55,20 @@ define( function( require ) {
     // the label
     var labelText = new Text( StringUtils.fillIn( distanceUnitsPatternString, { distance: 0 } ), {
       font: new PhetFont( 12 ),
-      bottom: arrowNode.top + ( 3 * HEAD_WIDTH / 4 )
+      bottom: arrowNode.top + ( 3 * HEAD_WIDTH / 4 ),
+      tandem: options.tandem.createTandem( 'labelNode' )
     } );
     this.addChild( labelText );
 
-    Property.multilink( [ mass1PositionProperty, mass2PositionProperty ], function( position1, position2 ) {
+    Property.multilink( [ model.object1.positionProperty, model.object2.positionProperty ], function( position1, position2 ) {
 
       // update the arrow node width
       var viewPosition1 = modelViewTransform.modelToViewX( position1 );
       var viewPosition2 = modelViewTransform.modelToViewX( position2 );
       arrowNode.setTailAndTip( viewPosition1, 0, viewPosition2, 0 );
 
       // update label text and center, distance in meters so divide by 1000 to read out in km
-      labelText.setText( StringUtils.fillIn( distanceUnitsPatternString, { distance: ( position2 - position1 ) / 1000 } ) );
+      labelText.setText( StringUtils.fillIn( distanceUnitsPatternString, { distance: model.distanceProperty.get() } ) );
 
       labelText.centerX = arrowNode.centerX;
     } );

diff --git a/js/gravity-force-lab-basics/view/GravityForceLabBasicsScreenView.js b/js/gravity-force-lab-basics/view/GravityForceLabBasicsScreenView.js
@@ -121,7 +121,7 @@ define( function( require ) {
     this.addChild( mass2Node.arrowNode );
 
     // arrow that shows distance between the two masses
-    var distanceArrowNode = new DistanceArrowNode( model.object1.positionProperty, model.object2.positionProperty, modelViewTransform, {
+    var distanceArrowNode = new DistanceArrowNode( model, modelViewTransform, {
       tandem: tandem.createTandem( 'distanceArrowNode' ),
       y: 145
     } );