auto-start video capture when querying, stop video on stop-all

HISTORY.md

@@ -81,6 +81,7 @@
 * Blocks, Objects, Threads: integrated video capture control into global settings prims in Sensing
 * Blocks, Threads: added a %self menu
 * Blocks, Threads, Objects: Finalized Video ops
+* Objects, Threads, GUI: auto-start video capture when querying, stop video on stop-all
 
 ### 2019-05-07
 * Blocks, Objects, Threads, Video: optimized video motion detection

snap.html

@@ -9,7 +9,7 @@
         <script type="text/javascript" src="src/blocks.js?version=2019-05-08"></script>
         <script type="text/javascript" src="src/threads.js?version=2019-05-08"></script>
         <script type="text/javascript" src="src/objects.js?version=2019-05-08"></script>
-        <script type="text/javascript" src="src/gui.js?version=2019-05-07"></script>
+        <script type="text/javascript" src="src/gui.js?version=2019-05-08"></script>
         <script type="text/javascript" src="src/paint.js?version=2019-02-22"></script>
         <script type="text/javascript" src="src/lists.js?version=2019-04-27"></script>
         <script type="text/javascript" src="src/byob.js?version=2019-02-15"></script>

src/gui.js

@@ -75,7 +75,7 @@ isRetinaSupported, SliderMorph, Animation, BoxMorph, MediaRecorder*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.gui = '2019-May-07';
+modules.gui = '2019-May-08';
 
 // Declarations
 

src/objects.js

@@ -7726,8 +7726,10 @@ StageMorph.prototype.fireStopAllEvent = function () {
 
     this.keysPressed = {};
     this.threads.stopAll();
-
     this.stopAllActiveSounds();
+    if (this.videoElement) {
+        this.stopVideo();
+    }
     this.children.forEach(function (morph) {
         if (morph.stopTalking) {
             morph.stopTalking();

src/threads.js

@@ -1907,6 +1907,9 @@ Process.prototype.doStopAll = function () {
             stage.keysPressed = {};
             stage.runStopScripts();
             stage.threads.stopAll();
+            if (stage.videoElement) {
+                stage.stopVideo();
+            }
             stage.children.forEach(function (morph) {
                 if (morph.stopTalking) {
                     morph.stopTalking();
@@ -4447,8 +4450,15 @@ Process.prototype.reportVideo = function(attribute, name) {
         stage = thisObj.parentThatIsA(StageMorph),
         thatObj = this.getOtherObject(name, thisObj, stage);
 
-    if (!stage || !stage.videoElement) {
-        return null;
+    if (!stage.videoElement || !stage.videoElement.stream) {
+        // wait until video is turned on
+        if (!this.context.accumulator) {
+            this.context.accumulator = true; // started video
+            stage.startVideo();
+        }
+        this.pushContext('doYield');
+        this.pushContext();
+        return;
     }
 
     switch (this.inputOption(attribute)) {