scaling a scene loaded from babylon file

[grire974]

This is probably quite a simple problem to solve; but I'm pretty new to BabylonJS.  I would like users of my code to be able to arbitrarily scale a 3D model loaded from a .babylon file using code like this:

 

BABYLON.SceneLoader.Load("", "model.babylon", engine, function (newScene) {newScene.executeWhenReady(function () {...

 

After the scene has been rendered using, 

 

engine.runRenderLoop(function() {newScene.render();});

 

I'm then trying to apply the user defined scaling value like this (for example 200% scaling):

 

for (i = 0; i < newScene.meshes.length; i++){        newScene.meshes[i].scaling = new BABYLON.Vector3(2, 2, 2);  } 

 

As you can see from the attached images of normal vs scaled;

 

the 200 percent scaled version isn't scaled proportionately; e.g. the wheels out grow the chassis of the vehicle.  Is this the correct way to scale a scene of multiple meshes?  Should I instead be adding all my meshes to a parent node and then scaling that? (if so how).

 

Appreciate the help; thanks!

 

[ChrisR]

This could be because the scale of the mesh before you set it isn't 1,1,1 (which is sometimes the case when importing meshes).

 

You could try,

for (i = 0; i < newScene.meshes.length; i++){        newScene.meshes[i].scaling.multiply(new BABYLON.Vector3(2, 2, 2));  } 

What happens to the mesh if you set it to (1,1,1) does the mesh change size?

[grire974]

Good question - I think I'd already tried that; Tried it again just to be sure... All 6 meshes are showing initial scaling of {x: 1, y: 1, z: 1}.. also noticed that you added the .multiply member of the Vector3 class into your code; so I tried some variations of that - however as you have it; I don't think it will have any effect as its a statement rather than an assignment, I did try something like this though:

newScene.meshes[i].scaling = newScene.meshes[i].scaling.multiply(new BABYLON.Vector3(2, 2, 2));

However this still gave me the out of proportion scaling shown in my 200 percent attachment.  Any other thoughts?

[GameMonetize]

a good idea would be to have an object which will be the parent of all others objects and just set parent.scaling = new BABYLON.Vector3(2, 2, 2);

[grire974]

Yeh I figured it would be something like that.. Using cocos3d I used something similar; attaching the model (including its meshes) to a node; & then performing scaling / positioning/ rotation operations on that parent node..

 

Looking at the API documentation for Babylon though; I'm not too sure how that might look; the Node class doesn't have the scaling member; and Scene doesn't seem to extend any other classes (nor does it have the scaling property either).

 

Any hints? 

 

p.s thanks for the quick reply!

[grire974]

more specifically I mean; what type of parent class should I be adding my imported .babylon file to? & what does the code for that look like?

[GameMonetize]

just create a box, make it like box.isVisible = false and then set myObject.parent = box

[grire974]

Thanks for that tip.. I tried something like this:

 

var m = BABYLON.Mesh.CreateBox('pmesh',15000, newScene);m.isVisible = false; for (i = 0; i < newScene.meshes.length; i++){         newScene.meshes[i].parent = m;}  m.scaling = new BABYLON.Vector3(2, 2, 2);

 

However, unfortunately it doesn't work; I get a javascript error with babylon.js: Uncaught RangeError: Maximum call stack size exceeded.  Its citing line 6; however the file is minified so I'm not so sure.  Before the error is thrown, there are numerous console logs: 

t.isEnabled @ babylon.js:6

 

Any thoughts?

[GameMonetize]

I think that this is because you try to set m.parent = m you have to check if newScene.meshes[i] !== m in your loop

[grire974]

aha! Of course.. Thanks for that.  For those of you reading the thread this was my code that solved it for me:

 

var m = BABYLON.Mesh.CreateBox('pmesh',15000, newScene);m.isVisible = false; for (i = 0; i < newScene.meshes.length; i++){                if(newScene.meshes[i].id == 'ground1'){continue}//substitute 'ground1' for the id of any mesh you don't want to scale                if(newScene.meshes[i].id == 'pmesh'){continue}                newScene.meshes[i].parent = m;}  m.scaling = new BABYLON.Vector3(2, 2, 2);//e.g. for 200% scaling

[grire974]

p.s. deltakosh - on a side note while I've got you here; not sure if you're interested but I made a fix to the FBX exporter visual c++ solution a couple of weeks back.. However couldn't get my pull request to be accepted; are there any permissions that I need to be aware of for the github repo?

[GameMonetize]

Hello!

 

No there is no permission: jsut fork it, make your fix, commit and create a pull request

[oschakravarthi]

Hi @Deltakosh

 

Can you please help with same problem explained in a different thread ?

Thanks in advance.

 

[Guest]

Hey we moved to a new forum: forum.babylonjs.com