Following Multiple blines


Help! I’m a newbie and took on a little project that requires animating an object over multiple blines. I am using 0.61.08-2026 and quickly learned the technique to follow a bline. Now I need to extend that capability to multiple blines.

The best approach seems to be through addition of a “linking bline”, but I can not seem to get my object to move across the linked vertex. I’ve attached an example and hope someone can offer some advice.

Linking_to_Multiple_blines.sifz (1.51 KB)

According to your example you want your object to follow several bilines joined. Why don’t do that with a single bline with several vertices? if anyway for some reason you want to do that with several blines you have a workaround for that:

In the Paste Canvas Origin parameter convert the BLine parameter to a Switch convert type. It would give you the followings parameters:
Link Off (BLine)
Link On (BLine)

Then convert again (as many times needed) one of the sub parameters to Switch type again:

BLine (LIST)
Link Off (BLine LIST)
Link Off BLine LIST) ()
Link On (BLine LIST) (
Link On (BLine LIST) (*)

Then export the three original bline LIST of each Outline Layer giving different names. FInnaly link the exported ones to the bline Lists marked with (*) and properly set the amount value an the boolean Switch parameter of each convert type to make the object “jump” from one bline to other.



Thanks for the quick reply. The reason I presented the issue this way is because I am animating a handwriting sequence with many repeating letters. I was hoping to make the animation process a bit more cut-and-paste instead of trying to draw each individual letter. I will give your suggestion a try and see which method is most efficient.

Ultimately, I just need to smoothly move the object from the end point of bline#1 to the starting point of bline#2. I’d appreciate any other ideas on how to do this.


I suggest to draw all the letters with different blines and then join them all with the Draw tool.
With the current status of the Draw tool it would be a little tricky but should work.

-First produce all the letters and remember where they start and end. It is important.
-Second, using the Draw tool select the followings options:
Create Outline (off)
Create Region (on)
All the rest of parameter to be off.
-Third, use the Draw tool with the CTRL key pressed all the time. Start to draw BEFORE the first letter begging and trace over all the vertexes each letter show. Remember to start tracing each letter from the beginning to the end of its creation (and the way they would be shown). Don be worry if the trace is not good. Just be sure that you pass over all the vertexes of each letter. Using CTRL it would override the current pen trace and only would look for the vertexes you pass over.

If everything went fine you’ll obtain a close region that has all the letters with it.

Now create a outline (any one) and select it ant eh previously created region at the same time. Link their Bline Lists. It would make a long outline that passes exactly over all the letters. Hide or delete the region. Now you can play with the outline and its width to make the animation. Insert more vertexes where needed to make not visible (width = 0) the connecting lines between letters.

When you reuse the bline letters (before tracing) be sure that you move the vertexes and keep the origin untouched. If you translate the origin and keep the bline relative position the Draw tracing would fail. It is a bug.

See the sample file. I’ve reused the ‘l’ letter. Please tell me if you got the idea. :slight_smile:

hello.sifz (4.43 KB)

so much problems because of synfig doesn’t have split/join tools…


:smiley: Got it, and it works a bit easier than drawing all the letters in a single bline. This is exactly what I was after! I’ll post my finished work (next week), although I doubt there’s much to be learned from the inexperienced!

Thanks for the prompt response!