Chain's animation

[Nix]

Hi everyone,
how can I animation this chain?
It is made up of many png images, placed in a group.
Thanks

[rodolforg]

I guess you could make the chain links follow a spline.

[Nix]

Hi, thank for your answer.
Yes but I don’t know how I could do it.
I can draw only a spline or I must draw a spline on each chain’s element?
After, how do I animate it?
Sorry but I’m new to studying software

[rodolforg]

There are some posts here about that matter. Check Synfig Wiki also.

[FirasH]

Here you can find the tutorial. I’ve updated it yesterday as it was unordered and difficult to follow:
https://wiki.synfig.org/Doc:Following_a_Spline

I think (didn’t try something similar though) you could create that type of animation as follows:

1. Draw an outline that defines the path of the chain
2. Take one single element of the chain and link its origin (plus Rotate Layer) to the outline
3. Export the value representing the position of the element along the Spline
4. Duplicate the element of the chain, make sure it is linked to the outline
5. Convert the parameter that defines the position of the element along the outline to Add and then add a constant value (try till you get the correct displacement)

Repeat till you complete the chain.
I’m writing this without Synfig opened so some parts are quite generic but it should work.

[FirasH]

I tried something quickly and this is my result:

If you spend a bit of time and tune all the parameters you should get the result.

@rodolforg I noticed that If I follow exactly the procedure of the tutorial, when the linked group (containing the red rectangle and the Rotate Layer) reaches on of the two “turns”, the Rotate Layer applies a rotation of 180° instead of 90°…

I’m not sure if that is an issue or something I got wrong so I converted it to scalar and multiplied by 0.5 to get what you see. (using master f806eb)

[rodolforg]

Even when following steps?

Following a spline: Serious problem and frustration

Alright, here is a step by step guide on how to do this: [Follow%20Spline] Create a spline Draw your arrow Put the arrow in a group layer Make sure the center point of the group layer is where you want your arrow to rotate around (most likely in the middle of the arrow). To achieve that you can hold Ctr while moving the center point of the group layer. This way the objects inside won’t be moved and you can place the handle where needed Be sure to align the blue handle of your gr…

[rodolforg]

@FirasH

Duplicate the element of the chain, make sure it is linked to the outline

Maybe use Duplicate layer to make it easier?

[FirasH]

I got the problem…
When linking the object to the Spline just select the origin of the Group Layer (containing the object and the Rotate Layer). Following the wiki I was also selecting the blue rotation handle of the Rotate Layer resulting in a doubled value of the applied rotation.

[FirasH]

How would you apply it?
I tried to “Connect” the Duplicate Layer to Transformation > Offset > Amount of the object following the Spline, but my result is that the Amount value now becomes not animated meaning that the animation of the value is lost.

I know Duplicate Layer is very powerful but sometimes I’m having a hard time understanding it.

I attached my test file (made with master so no idea if it is backwards compatible) if you want to try to use the Duplicate Layer: test_chain.sifz (2.8 KB)

[Nix]

Hi, i tried it and works! Thank you all