Implement inView property on objects to determine whether currently…

… seen by camera #18
povdocs · Nov 17, 2015 · 3ac3dcb · 3ac3dcb
1 parent 36075d7
commit 3ac3dcb
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Showing 5 changed files with 42 additions and 8 deletions.
diff --git a/build/vr.dev.js b/build/vr.dev.js
diff --git a/build/vr.js b/build/vr.js
diff --git a/build/vr.js.map b/build/vr.js.map
diff --git a/examples/index.html b/examples/index.html
@@ -38,6 +38,7 @@
             VR.cylinder().moveTo(2, 1, 1);
 
             var torus = VR.torus().moveTo(3, 2, 4);
+            var torusWasInView = false;
 
             var oldColor = new THREE.Color();
             VR.on('lookat', function () {
@@ -57,6 +58,11 @@
                 torus.rotateY(delta / 10);
 
                 soundSource.moveTo(10 * Math.cos(time / 1), 4, 0);
+
+                if (torus.inView && !torusWasInView) {
+                    torus.rotateX(Math.PI / 4);
+                }
+                torusWasInView = torus.inView;
             });
 
             VR.on('shake', function () {

diff --git a/src/vr-object.js b/src/vr-object.js
@@ -33,20 +33,34 @@ module.exports = (function () {
 		return object.geometry.boundingBox.distanceToPoint(scratchVector1);
 	}
 
-	function VRObject(parent, creator, camera, options) {
+	function VRObject(parent, creator, body, options) {
 		var material,
 			object,
 			self = this,
 
 			isNear = false,
 			isTarget = false,
+
+			camera = body && (function () {
+				var i,
+					c;
+				for (i = 0; i < body.children.length; i++) {
+					c = body.children[i];
+					if (c instanceof THREE.PerspectiveCamera) {
+						return c;
+					}
+				}
+			}()),
+			frustum,
+			cameraViewProjectionMatrix,
+
 			raycaster;
 
 		options = options || {};
 
 		eventEmitter(this);
 
-		if (camera) {
+		if (body) {
 			// raycaster = new THREE.Raycaster();
 
 			this.update = function () {
@@ -141,9 +155,23 @@ module.exports = (function () {
 
 		Object.defineProperty(this, 'distance', {
 			get: function () {
-				return distance(self.object, camera || parent);
+				return distance(self.object, body || parent);
 			}
 		});
+
+		if (camera) {
+			frustum = new THREE.Frustum();
+			cameraViewProjectionMatrix = new THREE.Matrix4();
+			Object.defineProperty(this, 'inView', {
+				get: function () {
+					camera.updateMatrixWorld(); // make sure the camera matrix is updated
+					camera.matrixWorldInverse.getInverse(camera.matrixWorld);
+					cameraViewProjectionMatrix.multiplyMatrices(camera.projectionMatrix, camera.matrixWorldInverse);
+					frustum.setFromMatrix(cameraViewProjectionMatrix);
+					return frustum.intersectsObject(self.object);
+				}
+			});
+		}
 	}
 
 	VRObject.prototype.hide = function () {