Animate rotation of an imported mesh

[spritefire]

Just trying to relearn things in babylon that I was using in three.js
Can't seem to find the answer anywhere (although I could be looking in the wrong direction or might be so simple I am over looking it).

I have a single mesh that I have exported from 3ds max. No animations just mesh and a texture. I have turned off the camera control and positioned the mesh nicely. Now I just want the mesh to rotate on a horizontal axis using babylon.
 

var container = document.getElementById('canvas');var engine, scene, camera;var internalMesh;function init(){ engine = new BABYLON.Engine(container, true);scene = new BABYLON.Scene(engine); BABYLON.SceneLoader.ImportMesh("", "", "desiren.babylon", scene, function (newMeshes){internalMesh = scene.getMeshByName("desiren_full");//internalMesh = newMeshes[0]; // Both ways find MeshinternalMesh.position = new BABYLON.Vector3.Zero;scene.clearColor = new BABYLON.Color4(1,0,0,0);    engine.runRenderLoop(function() {    scene.render();    internalMesh.rotation.x += 0.05;    });alert(internalMesh); // does return object}); camera = new BABYLON.ArcRotateCamera("Camera", Math.PI/2*3, Math.PI/2, 300, new BABYLON.Vector3(0, 0, 0), scene);var light = new BABYLON.HemisphericLight("Hemi0", new BABYLON.Vector3(0, 2, 0), scene);light.diffuse = new BABYLON.Color3(1, 1, 1);light.specular = new BABYLON.Color3(1, 1, 1);light.groundColor = new BABYLON.Color3(0, 0, 0);window.addEventListener("resize", function () { engine.resize(); }); // Resize engine }init();

Also, does the runRenderLoop function need to be called within the same function of the imported scene or is there another way of accessing the mesh outside of function?

I know this should be simple but I can't seem to find the answer anywhere. 
 

[Temechon]

Hi,

 

You can do this anywhere in the code (but once the mesh is loaded) : 

scene.registerBeforeRender(function() {   mesh.rotation.x += 0.05;});

[Wingnut]

Hi Spritefire and Temechon!

   Temechon (or anyone else), do you have a moment to expound on your answer?

Let's look at http://playground.babylonjs.com/?16

I happen to know that the skull's .name is 'test'.

So then I modify the scene's rbr func... to...

    scene.registerBeforeRender(function () {        light.position = camera.position;	scene.getMeshByName("test").rotation.y += 0.05;    });

Then hit run.  It doesn't work.

Then hit save.  Now it works (it once did, anyway).

Or does it?  http://playground.babylonjs.com/#NCF3T  (now no, but the rotation worked good when I made this save.  weird)

Can you explain to us... why this is?  I am seeing all sorts of inconsistencies.

Should scene.executeWhenReady() be involved somehow?  Know? 

Thanks either way.  Maybe it's something with the playground?

[amorgan]

I personally like to attach my meshes to my scene, so instead of declaring the internalMesh as a global I would do this instead:

scene.internalMesh = scene.getMeshByName("desiren_full");

then at the end of your scene creation I would create the registerBeforeRender and  call the runRenderLoop:

scene.registerBeforeRender(function () {	scene.internalMesh.rotation.y += 0.05;});engine.runRenderLoop(function() {    if (scene.isReady()) {        scene.render();    }});

Also if you look at the wiki (https://github.com/babylonjs/babylon.js/wiki) it is really valuable. As you expand out you will start finding things like the ActionManager and Animation functions that are really powerful. One thing I am discovering that as you expand, you don't really want to use the renderLoop for logic decisions. I actually created my own loop for logic creation using setTimeout and calling it recursively. Something like this:

var logicLoopId; //to identify the loop if you need to stop itvar logicLoop = function () {   logicLoopId = setTimeout(function () {      //logic   }, 10);   logicLoop();};//then call it in your code when you are ready to start itlogicLoop();

[Temechon]

@Wingnut : Try this : http://playground.babylonjs.com/#NCF3T#5

Indeed, your mesh must be loaded, otherwise it won't work.

[Wingnut]

Ahh, you put the rBR func inside-of the BABYLON.SceneLoader.ImportMesh function.  Well look at that.  Thx Temechon. 

 

@amorgon - thx for your informative comment, too.  Interesting!

[spritefire]

Thanks guys! 

I have learnt a ton and have discovered that the issue isn't related to coding at all. I have used what everyone has said and I have re-written the code and have it working perfectly if I use the skull.babylon file.

 

However, if I create a simple box in 3DS Max and export the file and place that babylon file into the code it will not rotate. 

If I export a basic mesh shape (the default teapot shape) from 3ds max using the 3ds exporter (v0.9 and v0.14 latest) and use that babylon file I am unable to get the mesh to rotate. 

 

Here is the max archive and also the code that is working fine with the skull:

 

        var canvas = document.getElementById("renderCanvas");        var engine = new BABYLON.Engine(canvas, true);        var createScene = function () {            var scene = new BABYLON.Scene(engine);            var light = new BABYLON.PointLight("Omni", new BABYLON.Vector3(20, 20, 100), scene);            var camera = new BABYLON.ArcRotateCamera("Camera", Math.PI/2*3, Math.PI/2, 100, new BABYLON.Vector3(0, 0, 0), scene);            //var camera = new BABYLON.ArcRotateCamera("Camera", 0, 0.8, 400, BABYLON.Vector3.Zero(), scene);            //camera.attachControl(canvas, false);            BABYLON.SceneLoader.ImportMesh("", "", "desiren.babylon", scene, function (newMeshes) {                    camera.target = newMeshes[0];                    scene.clearColor = new BABYLON.Color4(1,0,0,0);                    scene.registerBeforeRender(function () {                        scene.getMeshByName("test").rotation.y += 0.05;                    });            });                        return scene;        }                var scene = createScene();        engine.runRenderLoop(function () {            scene.render();        });        window.addEventListener("resize", function () { engine.resize(); }); // Resize engine 

http://spritefire.com/files/teapot.zip

 

http://spritefire.com/files/desiren.babylon

[Temechon]

Exported objects from 3dsmax has a rotationQuaternion set by default.

Try this : 

BABYLON.SceneLoader.ImportMesh("", "", "desiren.babylon", scene, function (newMeshes) {      camera.target = newMeshes[0];      scene.clearColor = new BABYLON.Color4(1,0,0,0);      scene.getMeshByName("test").rotationQuaternion = null;      scene.registerBeforeRender(function () {             scene.getMeshByName("test").rotation.y += 0.05;      });});

[spritefire]

 

Exported objects from 3dsmax has a rotationQuaternion set by default.

Try this : 

BABYLON.SceneLoader.ImportMesh("", "", "desiren.babylon", scene, function (newMeshes) {      camera.target = newMeshes[0];      scene.clearColor = new BABYLON.Color4(1,0,0,0);      scene.getMeshByName("test").rotationQuaternion = null;      scene.registerBeforeRender(function () {             scene.getMeshByName("test").rotation.y += 0.05;      });});

Perfect!