Merge pull request #28 from diarmidmackenzie/fix-infinite-loop-on-imp…

…ulse-refactor

Fix infinite loop on impulse

CannonDriver.md

@@ -227,7 +227,7 @@ el.body.applyImpulse(
 
 | event         | description                                                  |
 | ------------- | ------------------------------------------------------------ |
-| `body-loaded` | Fired when physics body (`el.body`) has been created.        |
+| `body-loaded` | Fired when physics body (`el.body`) has been created, and has a shape configured.  Also fired if the body's shape is modified later. |
 | `collide`     | Fired when two objects collide. Touching objects may fire `collide` events frequently. Unavailable with `driver: worker`. |
 
 ### Collisions

dist/aframe-physics-system.js

@@ -16819,7 +16819,7 @@ var Body = {
         this.shouldUpdateWireframe = true;
       }
 
-      this.isLoaded = true;
+      this.hasShape = true;
     }
 
     this.el.body = this.body;
@@ -16830,7 +16830,7 @@ var Body = {
       this._play();
     }
 
-    if (this.isLoaded) {
+    if (this.hasShape) {
       this.el.emit('body-loaded', {body: this.el.body});
     }
   },
@@ -16861,9 +16861,13 @@ var Body = {
 
   tick: function () {
     if (this.shouldUpdateBody) {
-      this.isLoaded = true;
-
-      this._play();
+
+      // Calling play will result in the object being re-added to the
+      // physics system with the updated body / shape data.
+      // But we mustn't add it twice, so any previously loaded body should be paused first.
+      this._pause();
+      this.hasShape = true;
+      this._play()
 
       this.el.emit('body-loaded', {body: this.el.body});
       this.shouldUpdateBody = false;
@@ -16879,13 +16883,16 @@ var Body = {
    * Registers the component with the physics system, if ready.
    */
   play: function () {
-    if (this.isLoaded) this._play();
+    this._play();
   },
 
   /**
    * Internal helper to register component with physics system.
    */
   _play: function () {
+
+    if (!this.hasShape) return;
+
     this.syncToPhysics();
     this.system.addComponent(this);
     this.system.addBody(this.body);
@@ -16896,10 +16903,13 @@ var Body = {
    * Unregisters the component with the physics system.
    */
   pause: function () {
-    if (this.isLoaded) this._pause();
+    this._pause();
   },
 
   _pause: function () {
+
+    if (!this.hasShape) return;
+
     this.system.removeComponent(this);
     if (this.body) this.system.removeBody(this.body);
     if (this.wireframe) this.el.sceneEl.object3D.remove(this.wireframe);

src/components/body/body.js

@@ -84,7 +84,7 @@ var Body = {
         this.shouldUpdateWireframe = true;
       }
 
-      this.isLoaded = true;
+      this.hasShape = true;
     }
 
     this.el.body = this.body;
@@ -95,7 +95,7 @@ var Body = {
       this._play();
     }
 
-    if (this.isLoaded) {
+    if (this.hasShape) {
       this.el.emit('body-loaded', {body: this.el.body});
     }
   },
@@ -126,9 +126,13 @@ var Body = {
 
   tick: function () {
     if (this.shouldUpdateBody) {
-      this.isLoaded = true;
-
-      this._play();
+
+      // Calling play will result in the object being re-added to the
+      // physics system with the updated body / shape data.
+      // But we mustn't add it twice, so any previously loaded body should be paused first.
+      this._pause();
+      this.hasShape = true;
+      this._play()
 
       this.el.emit('body-loaded', {body: this.el.body});
       this.shouldUpdateBody = false;
@@ -144,13 +148,16 @@ var Body = {
    * Registers the component with the physics system, if ready.
    */
   play: function () {
-    if (this.isLoaded) this._play();
+    this._play();
   },
 
   /**
    * Internal helper to register component with physics system.
    */
   _play: function () {
+
+    if (!this.hasShape) return;
+
     this.syncToPhysics();
     this.system.addComponent(this);
     this.system.addBody(this.body);
@@ -161,10 +168,13 @@ var Body = {
    * Unregisters the component with the physics system.
    */
   pause: function () {
-    if (this.isLoaded) this._pause();
+    this._pause();
   },
 
   _pause: function () {
+
+    if (!this.hasShape) return;
+
     this.system.removeComponent(this);
     if (this.body) this.system.removeBody(this.body);
     if (this.wireframe) this.el.sceneEl.object3D.remove(this.wireframe);

tests/physics/body.test.js

@@ -59,7 +59,7 @@ suite('body', function () {
     });
 
     test('pause', function () {
-      component.isLoaded = true;
+      component.hasShape = true;
       component.system = physics;
       component.body = el.body = body;
       component.pause();