add referenceLineNode.xDisplayProperty, #305

phetsims · Mar 28, 2023 · 77717e8 · 77717e8
1 parent e23fab3
commit 77717e8
Showing 1 changed file with 9 additions and 1 deletion.
diff --git a/js/common/view/ReferenceLineNode.ts b/js/common/view/ReferenceLineNode.ts
@@ -24,6 +24,8 @@ import ReferenceLine from '../model/ReferenceLine.js';
 import ScrubberNode from './ScrubberNode.js';
 import Multilink from '../../../../axon/js/Multilink.js';
 import Tandem from '../../../../tandem/js/Tandem.js';
+import Utils from '../../../../dot/js/Utils.js';
+import NumberIO from '../../../../tandem/js/types/NumberIO.js';
 
 // number of decimal places shown for the x value, dragging snaps to this interval
 const X_DECIMAL_PLACES = 1;
@@ -47,8 +49,14 @@ export default class ReferenceLineNode extends ScrubberNode {
       phetioHandleNodeVisiblePropertyInstrumented: false
     } );
 
+    const xDisplayProperty = new DerivedProperty( [ referenceLine.xProperty ],
+      x => Utils.roundToInterval( x, Math.pow( 10, -X_DECIMAL_PLACES ) ), {
+        tandem: tandem.createTandem( 'xDisplayProperty' ),
+        phetioValueType: NumberIO
+      } );
+
     // Create and add a numerical label at the top of the vertical line
-    const numberDisplay = new NumberDisplay( referenceLine.xProperty,
+    const numberDisplay = new NumberDisplay( xDisplayProperty,
       CalculusGrapherConstants.CURVE_X_RANGE, {
         align: 'center',
         decimalPlaces: X_DECIMAL_PLACES,