The Mask Editor is accessible from the main screen, as well as from the different modules that are able to apply a mask. The button to launch the Mask Editor is labelled 'Mask'. When launching the Mask Editor from a module, pressing the 'Keep' or 'Cancel' buttons will return StarTools to the module you pressed the 'Mask' button in.
As with the different modules in StarTools, the 'Keep' and 'Cancel' buttons work as expected; 'Keep' will keep the edited Mask and return, while 'Cancel' will revert to the Mask as it was before it was edited and return.
As indicated by the 'Click on the image to edit mask' message below the image, clicking on the image will allow you create or modify a Mask. What actually happens when you click the image, depends on the selected 'Brush mode'. While some of the 'Brush modes' seem complex in their workings, they are quite intuitive to use.
Apart from different brush modes to set/unset pixels in the mask, various other functions exist to make editing and creating a Mask even easier;
NOTE: To quickly turn on all pixels, click the 'clear' button, then the 'invert' button.
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