Mask transform keyframe speed

Hello!

Is there any way to change the sort of motion of a draw mask? I want it to move in a linear way rather than ease in and ease out. I know how to do this when you are using transform keyframes with the main clip but the mask doesn't appear to be popping up with the same dropdown menu to pick the sort of motion, (Excuse the lack of technical terms in this next bit) you can't activate the transform grid to right click on the line that indicates the movement that you want to change the nature of. There doesn't appear to be anything that will let you change this within the inspector.

Any ideas? must be possible! Thanks in advance

Note: This is a 'draw mask' effect, rather than within another effect

I don't believe you can change this behavior in FCPX, but you can probably do it in Motion. In FCPX if you are moving a mask from right to left (for example) you can trim the first few frames of the clip (about 8 to 10 in my testing) after the mask has been drawn, thereby eliminating the ease in behavior. If you have applied the mask at some point within the clip duration other than the beginning, this workaround would obviously not be practical. For clips with masks that start and end for the full clip duration, the trimming workaround would be OK. I would like to be able to click the keyframe in the animation editor and select the movement type, but it doesn't seem to be available for the masks.

Annoying that this can't be easily done, but thanks that's a good workaround! I do have motion and the skills to use it but it's total overkill for what I'm wanting to do - in theory, I've probably put more effort into researching the issue!
They really need to improve the ability to customise effects more in programme. Would save a lot of round tripping!
Thanks!

lkmarley wrote: Annoying that this can't be easily done, but thanks that's a good workaround! I do have motion and the skills to use it but it's total overkill for what I'm wanting to do - in theory, I've probably put more effort into researching the issue!
They really need to improve the ability to customise effects more in programme. Would save a lot of round tripping!
Thanks!

Here is another possible workaround - assuming the mask only changes position, and not shape or size.

1) Prepare the mask on one frame.
2) Share that frame as a still image, in png format (so it keeps the transparency - basically the masked area becomes opaque, the area outside is transparent).
3) Turn off the mask
4) Import the image back into your library, and connect it on top of the clip, changing its Blend Mode to "Stencil Alpha".
Now you have your mask again, except that you will move the mask by adjusting the position of the connected image - where you CAN set keyframes to linear

Smart! Yeah that's a good one, thank you. I managed to frankenstein this project together but will try that next time. It might actually be a good way to do it in general for some things.