I am a new GIMP user with a quick question. I am using "Add Layer Mask" and the radial gradient tool to create a transparent hole in a png layer. The radial gradient tool only applies maximum transparency at the cursor vector center fading to opacity at the end of the cursor vector. Is there a way set complete transparency over a circular region fading from complete transparency at the circle edge to the end of the cursor vector?
Just make a circle selection and bucket-fill it with black, leaving the rest of the mask white.
Explanation: the layer is opaque where the layer mask is white and transparent where the mask is black. Achieving complete transparency of the layer over a circular area is done by painting a black circle on a white mask, and painting a black circle is done by making a circle selection and bucket-filling it with black.