A mask uses the shape of one element to clip another, so the masked element only shows where the two overlap. It is the way to crop an image to a shape, for example.
You don't need a mask just to round an image. Image elements can round their own corners, all the way up to a full circle.
Create a mask
Select the masking element first (the shape that does the clipping), then the element you want to mask, and click Mask elements in the Toolbar. You need at least two elements selected.
The two slots
A mask holds two slots, both visible in the Layer Panel:
- the Masking Layers slot: the shape that clips.
- the Masked Layers slot: what shows through it.
Each slot can hold more than one element. Drag elements into and out of the slots in the Layer Panel to change what is masked, or what does the masking.
Options
In the Property Panel, a mask has two options:
- Invert: show the content outside the shape instead of inside it.
- Color masking: use the masking element's colour and brightness to set transparency, instead of just its outline.
Remove a mask
To undo a mask, drag its elements out of both slots in the Layer Panel, then delete the now-empty mask.