Select a brush tip. This can be a generated brush tip (round, square, star-shaped), a predefined bitmap brush tip, a custom brush tip or a text. 2. Select the spacing: this determines how many impressions definitions files of these applications: abr Gimp autobrush tip definitions. *.gbr Gimp single bitmap brush tip. Can be black and white or colored. *.gih Gimp Image Hose brush tip: contains a series predefined brush tips are shown in one selector. There are four more options that influence the initial bitmap brush tip you start painting with: Size Scales the brush tip. 1.0 is the native size of the brush