add lightSpeed query parameter, #71

phetsims · Sep 22, 2021 · c6690da · c6690da
1 parent 01ed634
commit c6690da
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Showing 3 changed files with 10 additions and 4 deletions.
diff --git a/js/common/GeometricOpticsConstants.js b/js/common/GeometricOpticsConstants.js
@@ -32,8 +32,7 @@ const GeometricOpticsConstants = {
   ORIGIN_POINT: new Vector2( 1024 / 2, 618 / 2 - 50 ), // view position of the model origin (0,0)
   NOMINAL_VIEW_MODEL_CONVERSION: 2, // view coordinates per cm in initial zoom level
 
-  LIGHT_SPEED: 500, // speed in centimeter per second for light for the purpose of the animation
-  RAYS_ANIMATION_TIME: 5, // length of the rays animation, in seconds
+  RAYS_ANIMATION_TIME: 10, // length of the rays animation, in seconds
 
   //----------------------------------------------------------------------------------------
   //                                 LENS

diff --git a/js/common/GeometricOpticsQueryParameters.js b/js/common/GeometricOpticsQueryParameters.js
@@ -35,6 +35,13 @@ const GeometricOpticsQueryParameters = QueryStringMachine.getAll( {
   // show the position of points at a distance 2f from the optic.
   show2fPoints: {
     type: 'flag'
+  },
+
+  // speed of light in centimeters per second, for the purpose of the light rays animation
+  lightSpeed: {
+    type: 'number',
+    defaultValue: 500,
+    isValidValue: value => ( value >= 100 )
   }
 } );
 

diff --git a/js/common/model/LightRay.js b/js/common/model/LightRay.js
@@ -15,7 +15,7 @@ import Vector2 from '../../../../dot/js/Vector2.js';
 import Shape from '../../../../kite/js/Shape.js';
 import AssertUtils from '../../../../phetcommon/js/AssertUtils.js';
 import geometricOptics from '../../geometricOptics.js';
-import GeometricOpticsConstants from '../GeometricOpticsConstants.js';
+import GeometricOpticsQueryParameters from '../GeometricOpticsQueryParameters.js';
 import Optic from './Optic.js';
 import Ray from './Ray.js';
 
@@ -50,7 +50,7 @@ class LightRay {
     this.virtualShape = new Shape();
 
     // {number} maximum travel distance if ray is unimpeded
-    const distanceTraveled = GeometricOpticsConstants.LIGHT_SPEED * time;
+    const distanceTraveled = GeometricOpticsQueryParameters.lightSpeed * time;
 
     // {Vector2|null} first intersection point - a null value implies that the initialRay does not intersect the optic
     const firstPoint = this.getFirstPoint( initialRay, optic, isPrincipalRayMode );