Howdy folks, working on the ui for a game at university, but having trouble trying to turn the minimap into a circle as opposed to a square so i can import the outer asset (the cog). Any help would be appreciated! 
The technique is called “masking”. You just need a sprite mask that covers the area that should not be drawn and I think you somehow have to stack that onto the actual rectangular sprite. It’s been a while that I used that, the manual should be of help.