Animating a hole in an object

Support Basics & Interface
1

Greetings everyone,
I’m new to Blender so I imagine this is really simple yet I can’t figure out how to do it. :slight_smile: What I’m trying to do is take an object (an octagon) and start it off with a no hole and then as it progresses a big hole forms in the center of it. Can anyone assist with me this? Thank you in advance.

2

You can either use an animated texture to change the alpha of you octagon some way you’ll like. You should find everything you’ll need in this tutorial by B@rt :
http://vrotvrot.com/xoom/tutorials/Welder/Welder.html

3

Ok.This may not be the best way to do it but it should work. Start off with your octagon. Then duplicate it in edit mode and slale the new one down slightly. Highlight all verticees and press x followed by only faces.Now build the faces with the F key but do not fill in the hole part in the middle. Do this with a series of traingles and/or squares. Now highlight the outer verticees and press Shift+S and chose Cursor->selscted. Not choose the inner ones and choose Sel–> cursor. Highlight the whole mesh can press I. Chose Mesh.Move a head a few frames. Now press B and highlight all the middle verticees together and scale them apart. Insert Mesh again. The hole should expand to that size over the set amount of frames.

I hope I explained this well enough. Reply and tell me if it works.

4

When I go to scale the inner verticles after sel --> cursor, it doesn’t open up the hole. Maybe I did something wrong?

5

Here’s a fairly simple solution:

-Make the octagon out of a bezier circle.
-while still in edit mode, add another bezier circle in the middle of the octagon.
-size this new circle to zero select all vertices and set a curve key (‘i’ key and select curve)
-Now resize the circle to whatever size you want the hole and then select all vertices again and set a second curve key (‘i’ key and select curve)
-exit from edit mode (tab)
-Now you can edit the hole opening and closing using the ipo window and manipulating the curve between the two set points you set above.

If you need an example file I can email one to you.

Hope that helps!