add LightSpot.intersectsProjectionScreenProperty, use it to set visib…

…ility of LightSpotNode and therefore filter out tool jump points, #426
phetsims · Apr 13, 2022 · 8569d01 · 8569d01
1 parent c3fa96c
commit 8569d01
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Showing 3 changed files with 37 additions and 11 deletions.
diff --git a/js/common/model/LightSpot.ts b/js/common/model/LightSpot.ts
@@ -23,6 +23,7 @@ import PhetioObject, { PhetioObjectOptions } from '../../../../tandem/js/PhetioO
 import optionize from '../../../../phet-core/js/optionize.js';
 import PickRequired from '../../../../phet-core/js/types/PickRequired.js';
 import PickOptional from '../../../../phet-core/js/types/PickOptional.js';
+import BooleanIO from '../../../../tandem/js/types/BooleanIO.js';
 
 type PositionAndDiameter = {
   position: Vector2; // position of the light spot's center, in the vertical plane of the projection screen
@@ -40,12 +41,15 @@ export default class LightSpot extends PhetioObject {
   // Intensity of the light spot, in the range [0,1], 0 if there is no light spot hitting the projection screen
   public readonly intensityProperty: IReadOnlyProperty<number>;
 
-  // Position of the center of the light spot, which may not be on the screen,
+  // Position of the center of the light spot, which may not be on the screen
   public readonly positionProperty: IReadOnlyProperty<Vector2>;
 
-  // Diameter of the light spot in the y dimension,
+  // Diameter of the light spot in the y dimension
   public readonly diameterProperty: IReadOnlyProperty<number>;
 
+  // Whether the light spot intersects the projection screen
+  public readonly intersectsProjectionScreenProperty: IReadOnlyProperty<boolean>;
+
   constructor( optic: Optic,
                projectionScreen: ProjectionScreen,
                lightObjectPositionProperty: IReadOnlyProperty<Vector2>,
@@ -107,6 +111,15 @@ export default class LightSpot extends PhetioObject {
         phetioType: DerivedProperty.DerivedPropertyIO( NullableIO( NumberIO ) ),
         phetioDocumentation: 'intensity of the light spot, in the range [0,1]'
       } );
+
+    this.intersectsProjectionScreenProperty = new DerivedProperty(
+      [ this.positionProperty, this.diameterProperty, projectionScreen.positionProperty ],
+      ( position: Vector2, diameter: number, projectionScreenPosition: Vector2 ) =>
+        position.y >= projectionScreenPosition.y - projectionScreen.height / 2 - diameter / 2 &&
+        position.y <= projectionScreenPosition.y + projectionScreen.height / 2 + diameter / 2, {
+        tandem: options.tandem.createTandem( 'intersectsProjectionScreenProperty' ),
+        phetioType: DerivedProperty.DerivedPropertyIO( BooleanIO )
+      } );
   }
 
   public override dispose(): void {

diff --git a/js/common/model/ProjectionScreen.ts b/js/common/model/ProjectionScreen.ts
@@ -38,6 +38,9 @@ export default class ProjectionScreen extends PhetioObject {
   // Shape of the screen, relative to positionProperty
   public readonly screenShape: Shape;
 
+  // Height of the screen at its centerX.
+  public readonly height: number;
+
   // line that vertically bisects the screen, relative to positionProperty
   private readonly bisectorLine: Shape;
 
@@ -69,11 +72,13 @@ export default class ProjectionScreen extends PhetioObject {
       .lineTo( -SCREEN_WIDTH / 2, -SCREEN_FAR_HEIGHT / 2 )
       .close();
 
+    // Height at the centerX of the screen, the average of its near and far perspective heights
+    this.height = ( SCREEN_NEAR_HEIGHT + SCREEN_FAR_HEIGHT ) / 2;
+
     // Described from top to bottom, in model coordinates.
-    const averageScreenHeight = ( SCREEN_NEAR_HEIGHT + SCREEN_FAR_HEIGHT ) / 2;
     this.bisectorLine = new Shape()
-      .moveTo( 0, averageScreenHeight / 2 )
-      .lineTo( 0, -averageScreenHeight / 2 );
+      .moveTo( 0, this.height / 2 )
+      .lineTo( 0, -this.height / 2 );
 
     this.resetProjectionScreen = () => {
       this.positionProperty.reset();

diff --git a/js/common/view/LightSceneNode.ts b/js/common/view/LightSceneNode.ts
@@ -135,7 +135,11 @@ export default class LightSceneNode extends GOSceneNode {
     // LightSpot associated with the first light
     const lightSpot1NodeTandem = providedOptions.tandem.createTandem( 'lightSpot1Node' );
     const lightSpot1Node = new LightSpotNode( scene.lightSpot1, scene.projectionScreen, modelViewTransform, {
-      visibleProperty: DerivedProperty.and( [ lightPropagationEnabledProperty, scene.opticalImage1.visibleProperty ], {
+      visibleProperty: DerivedProperty.and( [
+        scene.lightSpot1.intersectsProjectionScreenProperty,
+        lightPropagationEnabledProperty,
+        scene.opticalImage1.visibleProperty
+      ], {
         tandem: lightSpot1NodeTandem.createTandem( 'visibleProperty' ),
         phetioType: DerivedProperty.DerivedPropertyIO( BooleanIO )
       } ),
@@ -146,11 +150,15 @@ export default class LightSceneNode extends GOSceneNode {
     // LightSpot associated with the second light
     const lightSpot2NodeTandem = providedOptions.tandem.createTandem( 'lightSpot2Node' );
     const lightSpot2Node = new LightSpotNode( scene.lightSpot2, scene.projectionScreen, modelViewTransform, {
-      visibleProperty: DerivedProperty.and(
-        [ lightPropagationEnabledProperty, scene.opticalImage2.visibleProperty, visibleProperties.secondPointVisibleProperty ], {
-          tandem: lightSpot2NodeTandem.createTandem( 'visibleProperty' ),
-          phetioType: DerivedProperty.DerivedPropertyIO( BooleanIO )
-        } ),
+      visibleProperty: DerivedProperty.and( [
+        scene.lightSpot2.intersectsProjectionScreenProperty,
+        lightPropagationEnabledProperty,
+        scene.opticalImage2.visibleProperty,
+        visibleProperties.secondPointVisibleProperty
+      ], {
+        tandem: lightSpot2NodeTandem.createTandem( 'visibleProperty' ),
+        phetioType: DerivedProperty.DerivedPropertyIO( BooleanIO )
+      } ),
       tandem: lightSpot2NodeTandem
     } );
     this.opticalImagesLayer.addChild( lightSpot2Node );