Having trouble with vertex animation

Hi all,

I’m wanting to do some fairly simple animations but I don’t think I’m understanding the virtues of relative vertex keys.

Basically, I’m trying to animate a letter T so that it twists (if that makes any sense).

I tried reading the manual online and I thought I was heading on the right track.

I created a reference by haveing the letter T without deformation hitting I and the Mesh and selecting Relative.

Then I selected the vertex I needed, set the rotation angle and hit I and then Mesh to store the next key.

Then I selected the next group of vertices and rotated it to the appropriate angle and hit I and then Mesh again.

From my understanding of the documentation, I should now be able to use Key 1 and Key 2 to animate the rotation/twisting effect using the IPO window.

However, when I do so and try it out in animation, nothing happens.

Sorry this is a bit difficult to explain.

Here’s what I want the T to do.

http://www.calebblake.com/blender/t.jpg

I hope this is kinda explaining what I’m trying to do. Any help would be appreciated.

Regards
Caleb

Can you upload the blend file somewhere for us to see? For specific cases, it’s always easier that way.

Martin

In particular, what do the actual IPO-curves look like? Are they there?

Yes the IPO curves are there.
On the whole, I set up three keys (using rotation with selected vertices).
I put them all in different frames so that they are distinguishable on the IPO screen.

I end up with my reference line in orange and 3 blue lines representing each of the keys.

Then I select Key 1 and draw a curve.

If I understand the documentation, the values from 0 to 1 are the most pertinent.

Therefore, I draw a curve from frame 20 to 80 (for example) going from 0 to 1 approx.

Then I go back to my 3D window and hit animate.
I cycle through the frames but nothing happens. I’ve still got boring mister T.

If I get time when I am at home I will post the blend to see if anyone can help sort me out on this one.

I know I must be doing something wrong. I just don’t know what it is.

Regards
Caleb

Here is the standard tutorial for explaining relative vertex keys:

http://bec.physics.udel.edu/blender/relkey/rel_key.html

The most likely thing that is causing your problem is that you are inserting all your keys in Edit mode.

Blender uses the Tabbing in and out of Edit mode to set your key.

So a simple example using the default scene:

[!] add a second ipo window and change the ipo type in the header to Vertex.
[!] cube in Object mode, press [I] > mesh. (There’s your base yellow key in the IPO curve window.
[!] press [I] a second time. (There’s your 2nd rvk. Hold down Ctrl_Shift and shift it up to 0.1, so it’s easier to select).
[!] repeat the above step as many times as you need to add rvks.
[!] select the 2nd rvk (blue). In edit mode make some modification to the cube and then [TAB] out of edit mode. The cube will snap back to the default shape, but the key is saved. In the IPO window select the base key, then the blue rvk - you should see it change shape.
[!] select each additional blue rvk and in turn, edit the mesh and [TAB] out to store it.

Not sure if this is the right/most efficient way to do it, but I know it works.

Hey - that tutorial is much better than what’s in the manual unless I read the manual completely wrong.

I have now got some animation working (1st 50 frames).
However, the second 100 frames don’t work as I expected (the second two keys).

I’ve got a link to the blend if anyone wants to have a look at what I’ve done wrong. Hell - you can even correct it for me and repost if you like. :smiley:

But just advice is fine too.

T1.blend
Right-click and save target.

Regards
Caleb

Yeah I had a look… obvious problem but not so easy to see at first.

See relative keys work because it saves the verts position relative to it’s starting point… and never relative to another key.

Basicly what you do is… The top of the T is in the same position relative to the start point in all keys… so that really doesn’t want to move after the first key hits 1. But you keep twisting the bit below it more and more, so it gets screwy.

In all honesty I think you could do this better with an armature.