Animate Visibility on Objects?

HI there… I’m trying to animate the visibility on objects in my scene. Since I don’t know how to do it, I’ve been trying to animate the Alpha on the materials. However, this isn’t solving the problem, as the objects still cast shadows and are showing specularity/etc. If I just want the whole object to disappear at some point in time, how do I accomplish that?

I did see a post about animating a layer, but I don’t know how to do that.

Also… if I want to change/animate a property on an object that has several sub-materials on it, is there anyway to do that with one change that affects all of the sub-materials or do you need to go into each one and change/keyframe the property? I’m just wondering if there’s a “master” change you can make that affects all sub-materials…

Thanks for any help!


Animating a layer is easy.

  • Select the object that you want to animate and press the “I” key for the Insert Key menu. Add a key for Layer.
  • Move to the frame that you want the object to change layers on.
  • Move the object to a new layer and make that layer active
  • With the object selected, press “I” again and insert another Layer key.Your object should now change layers as keyed. Hope this helps.

there’s a button TraShadow where transparent objects cast, and materials receive, shadows from transparent objects. See user manual on raytraced transparency.

Thanks for the info on how to animate Layers and how to disable transparent objects from casting shadows!

Does anyone know about sub-materials issue?


if by sub you mean multiple, click here.

I appreciate the link for the Multiple Materials, but I don’t see where it explains when you want to animate material properties.

To simplify what I’m asking… think of this example:

You have an object with 5 different (multiple) materials on it. They all have a certain Specularity value (the same value), but now you realize you want to change that value on all materials on that object. Is there any way to do that only once and have it affect all materials on the object, or do you have to go in to each material and change it each time?

I guess I’m just hoping for a shortcut on this. If you had something like 10 or more materials on one object, it would get pretty time-consuming to go back into each index and change it each time.

Thanks for your responses and your patience with me thus far.

Just link each material to the same Ipo.

When you add new keys for a material, it assigns a new Ipo to that material. For each material, it will assign a unique Ipo, unless you specify one.

Simply animate your settings for one material, then for each of the other materials, link to that Ipo in the Ipo editor.

I think that should do it.

Ahhh… does linking the IPO still work if all those multiple materials have different values? Or can you simply create an IPO based on an existing one, change the values for the properties you need for certain curves and then link it when you need it?
Or a better question is: can you add a single IPO curve to an existing IPO? In other words, could you do what you suggested by creating an IPO for animating one property change, so the IPO has only one curve. Then, if all the multiple materials have varying IPO curves, can you link (or somehow copy/paste) that single IPO curve into each multiple material to either add that IPO curve or replace an existing IPO curve?

Hi jdwpaint,

Well, it will work if the materials have different values, but not if all those values have to be animated. For instance, if you had one object with an alpha of 1.0 and another with 0.5 AND you wanted to animate both alpha channels to 0.0 over a few seconds, you wouldn’t want to animate them with the same Ipo, because it would enforce an absolute alpha value on both materials along the curve; i.e., from 1.0 to 0.0 or 0.5 to 0.0.

You can however copy and paste curves from one Ipo to another. There are copy and paste buttons (little up and down arrows) on the Ipo header. Just select a curve, copy to buffer, select the new value in the new Ipo, and paste.

Well, that’s pretty cool about the ability to copy/paste IPO curves!
You are leaning towards what I’m trying to figure out… basically how to animate the visibility on objects using materials (although other properties would be helpful also), as there was a post by Fligh a while back on this suggesting that it must be done through materials to achieve a gradual disappearance of your object?
You’re saying to animate the alpha one time, and then link that IPO to all the other materials… right? Am I correct that the only place the Alpha value slider is located is in the Materials panel? I ask this because I want to make sure that it cannot be done at the Object/Mesh level… that’s what I was hoping for at first… that somehow you could make a keyframe change that would propogate through all the multiple materials on an object/mesh… assuming as you mentioned that all the properties you were changing were to start and end at the same value, in this case the Alpha… let’s say we’re going from 1 to 0.
And animating the alpha would make it a MatIpo, right? So i’m guessing on the issue of animating a gradual visibility on an object with many materials on it, that I would have to select each material index and go to the IPO window each time, select the Materials drop-down menu and link (or copy/paste) our Alpha IPO animation curve to each specific material index… rather than being able to do it on an Object level one time?
I hope that makes sense… I know I’ve been rambling on.
Thanks for all the help so far!


It would be nice to see an object level transparency setting, but it’s in the material settings. As far as I know, there isn’t an object level equivalent. However if you don’t need to fade the transparency, if you only need the object to appear and disappear instantly, you can animate the object’s layer.

Thats exactly right.

Yes. Here’s a scenario where you might want to copy curves instead of just linking Ipos. Let’s say you have two materials, one animates from red to green, the other from red to blue. Because you need different anims on the same curves (RGB) you need to have a separate Ipo for each material. Now let’s say you want to fade both materials in and out over time. You can animate the alpha for one, but you can’t link both to the same Ipo because they need their own individual RGB keys for the different color anims. In this case it would be easier to animate alpha for one material, and then just paste the curve into the other Ipo.

You’re very welcome! I’m glad I could help. :smiley:

Awesome… thanks!

I have to say… that after trying out Blender last year, I don’t really have any reason to go back to Maya and learn any more of that program… there are so many powerful features in Blender that just cease to amaze me.

And whenever I find something small to complain about in Blender, I always remind myself and shake my head in disbelief that the program is free.

Thanks again!

Hi, new to the forum!
I’ve just started using blender for games production (been using Maya for 8 years) I need a way to animate visability on a object (not in lyaers or materials, this is for games production) there must be a way to do it…right?!

Any help much appreciated,

Can this be done in 2.5, I don’t see an option for “add a key for layer” when I hit the “I” key?

I’m also bummed by doing this in 2.5. While the visibility of layers can be keyed from the UI I can’t seem to get a list of keys that aren’t really exposed otherwise.

There aren’t a list of things that you can animate because almost the whole interface can be keyframes. Right mouse click over anything you want to animate and select add keyframe which will then show in the graph editor.
If you want to animate an objects visibility in 2.5 you don’t need to use the animate/move layer method. You can keyframe its visibility and rederability directly from the outliner. Right click on the eye symbol and select add keyframe to keyframe its on/off position.

Well in my case I do want to move stuff away to another layer as I only have planes that look behave very similarly so it’s a bit confsing to select the right stuff in the 3D view. I’m pretty sure I saw someone animate object layer movement, but I really can’t figure out how to key that.

Edit: ended up toggling textures within a material on a single plane instead, which is also pretty clear. Am still interested in the layer key though

Keyframe the objects layer using the layer settings in the object panel not the layers in the 3d view header. Just right click with you mouse over the layers and select add keyframe. It will then keyframe whatever layer the object is on.

Aha, the ‘relations’ group in the object buttons. Thank you!

awesome, just what I was looking for. Thanks