Typical problem with "in front" and "behind"

Its the typical triangle relation problem. I have the arms that are initially behind the shirt. If i want to move the arm to the front, it needs to be partially in front of the shirt and on other parts (shoulder) behind it. Is there some kind of general pattern to solve this problem?

For better explanation i appended this image:

Somehow this is a general problem in vector graphics that you will need to split it up in parts. On the other hand this is now animated, so it isn’t easily to split and keep it as you want it. If you have any tips to solve this problem in Synfig (general case preferred), let me know, please.

There is not general rule and probably dpends on how’s the original composition made.

But here are some tips:

At some point, the shirt-arm-shirt chain has to be broken so or you split the arm in two pieces or you split the shirt in two pieces. It depends on the geometry of the shirt and arm and its relative animation.
Once decided which part is split you have to clone it (yes we need a clone layer action! :wink:) and place it just over the other part of the triangle in its scope. When you have to make the split part to be over make its composite method set to Composite when you have to put the split part behind then change the composition method to Behind. So the animation is made by the animation of the blend method. Using the Z depth is also possible but needs more precision and also take care of the number of layers involved on each part.

Example: you split the arm

-Shirt layers
-Arm layers


-Arm layers bottom clone (Behind/ Composite)
-Shirt layers
-Arm layers top
-Arm layers bottom

Hope it makes sense :wink:


So far i understood it. Now i have the next problem (guess it is related to the “insert” approach i was talking about in the other thread). I have drawn the lines for Frame 40. Now i want to have exactly this position at frame 40 and to modify it for frame “0”. How can i modifiy frame 0 and keep frame 40? (No Keys inserted up till now, at least for this parts)

I think that you have to review the concept of keyframe and waypoint.
Short summary:
Waypoints are defined per layer parameter (or per value node if it was exported or linked) and contains the parameter value, the frame where the value is placed and the in/out interpolation modes. Usually they are represented in the timeline as green dots but can be yellow, cyan or red for each different interpolation mode.

Keyframes are frames that the user define to be “poses” of the art work so the modifications of the composition made around this frame doesn’t modify the values of the layers at the keyframe according to the lock keyframes policy.

See this:

So the solution is: create a keyframe at frame 40f, be sure that the lock keyframe button is set to lock all keyframes, then go to frame 0f and in animation mode, modify your artwork. Notice that it won’t produce a waypoint at the keyframe at frame 40f for a certain parameter unless you modify the value at frame 0f.


OK. I get it. Now i want to get rid of my keyframes (have no use for them currently). Only thing that worries me: All waypoints associated with it will also be removed if i remove the keyframe, destroying my current animation. Any way just to remove the keyframe without removing the waypoints?

Yes but it is a bit a workaround:
Encapsulate the layers involved. At the encapsulated layer click on the wayipoint at the keyframe and shift it a frame left or right, it will move all the children waypoints because that waypoint is the representation of all the children waypoints at that frame. Then delete the cleaned keyframe.

Thanks. It worked fine luckily i had some unused frames :wink:

Currently i’m still making experiments, but this is how far i got so far, even if its just a basic and very short animation. :wink:

The girl design is pretty good. It’s animation can be improved though. Seems like it is floating from keyframe to keyframe. You have to experiment with other kind of interpolation or arr more waypoints to control the bounces appearing. Also the timing can be a bit quicker.
I think that you’re just experimenting and just placed the keyframes equal separated in time and just testing the animation capabilities. Great character in any case!!

We definitively need another type of interpolation that were between ease and default TCB as suggested by rylleman in other thread.

I didn’t paid so much attention to the animation currently. Because im still adding parts that i need.

For the interpolation:
Most of this problems can be fixed with the parameters from TCB itself. But it is really hard to do so, since you have no indication how you effect the current animation. The earlier mentioned preview of the path of selected vertices inside the canvas could help a lot.

I think also that the onion-skin feature needs an addition. The best way i have seen so far was it do display up to 3 frames in every direction (not keyframes, real frames). Every frame got desaturated and colored with a hue-value, forming a nice rainbow, to distinguish frames from each other and blended over each other with soft downfalling transparency.