Write-on effect curved line and straight line

[Kohiko]

I'm making a whiteboard video with the write-on effect in AE. But somehow halfway through the write-on line changed from a line with curving/smooth lines to straight lines (see attachment). On the left the line curves as I make a circle, suddenly that stopped on the right.

What did I do wrong? 

[Mylenium · Accepted solution]

That's entirely dependent on your keyframe timing and easing, but since you aren't showing us your keyframes and paths we can't tell you much about it. The solution would be to spread out the keyframes and apparently adjust their easing.

Mylenium

[Kohiko]

Thanks for your quick reply! Here is a screenshot of my keyframes. The line on the left side of the drawing automatically adjust its curves depending on where the next keyframe is.

[Mylenium · Accepted solution]

Select the keyframes, righ-click and change the keyframe interpolation. Apparently this is some weird bug, but the other way around than you would think. The effect calculates a Bezier interpolation for the first few keyframes even if they are set to linear. This seems to have lingered ever since the old days as I can even replicate it here on my old decrepit machine using CS6.

Mylenium

[Kohiko]

Thank you so much for your help! To bad it's a bug but I can finish my project now :). 

[Rick Gerard]

I'm not sure what motion path you were trying to adjust, but you can open any layer in the layer panel and select the property with any kind of motion path, then edit that path with the pen tools. I almost never rely on spatial path interpolation to edit motion paths. 

Here's how to edit a Write On Path in the Layer Panel: