Simplest way to make this shape into a mask

[Robert344938760xac]

I'm trying to use the Video Copilot: Saber effect on this shape, but I'm under the impression it first must be turned into a mask. 

One guide I followed had me use the auto-trace but that created like 30 keyframes that wound back and forth. Is there a simpler way to make this exact shape? It seems so simple, and because I don't truly understand masks, I don't understand why I can't just copy/paste this somewhere, haha.

Thank you!

[Warren Heaton · Accepted solution]

Select the path and paste the path.

For example, expand Shape > Contents > Shape 1 > Path 1 > Path, then select Path and choose Edit > Copy (command C, Mac; control C, Windows).  If a Mask isn't already applied to the Layer receiving the copied Path, select the Layer and choose Layer > Mask > New Mask.  On that Layer, expand Masks > Mask 1 > Mask Path.  Select Mask Path and then choose Edit > Paste.(command V, Mac; control V, Windows).

[Robert344938760xac]

THANK YOU!

[Robert344938760xac]

I only want the "trim path effect" to progress from the bottom left and grow into the top right. Currently it starts in the top right, goes down to bottom left, and returns to top right. Any ideas on how to achieve this?

To achieve this mask, I used the auto-trace feature on a shape path I had. See here for more details.

(It seems like attached videos don't work right now, so I'll also upload it to YouTube and link it)

Thank you!

[Robert344938760xac]

The solution was given to me by just making a way simpler path. Here 

Thank you! @Warren Heaton 

[nishu_kush]

Merging the duplicate thread.

Thanks,
Nishu

[Warren Heaton]

To have the Saber effect start at the bottom instead of the top, change what's called the First Vertex on the Mask Path.

Each point on a Mask Path is a vertex and the one that starts the path is the first.  When using an effect that has a "Start" and "End" option, the First Vertex is the start.  If it's a closed path, it's also the end.

To easily view each vertex, I usually press m twice to show all Mask properties or press f once to show just Mask Feather while the Layer is selected in the Timeline and then select Mask Feather to see the Mask and each vertex of it in the Composition panel.  There's one point that's slightly larger than the others - that's the First Vertex.  To set a different point, hover over it with the mouse and then right-click and choose "Set First Vertex".  If an effect like Saber is already applied, that should now be the Start for it.