solder mask free area in Altium?

[xzswq21]

Hello
I want to define a solder mask free area on a PCB.
how should I define?
I couldn't find anything

[Deni]

Just draw on the solder mask layer whatever you want. Altium will correctly generate negative gerber images

[ncoonrod14]

First select the top solder layer and then use any of the shape options in the place menu. Alternatively, if you need something that isn't a line, rectangle, or arc. You can make the outline of what you want filled using the above tools, select those objects, and got to Tools/Convert/Create Polygon from selected primitives.