Dynamic+Brushes+in+GIMP

Creating a brush with variable size
You can create a brush with a size which will vary by rotating the mouse wheel or by using the keyboard arrow keys. Start with opening the Brush dialog by double_clicking on the Brush area in Toolbox, or by going through File → Dialogs → Brushes. Click on the New Brush button to open the Brush Editor dialog. Name your brush at once, “Dynamic” for instance. Your brush will appear in the Brush Dialog with a blue corner. Now, go to File → Preferences → Input Controllers. Check the Enable this controller box. Scroll through the Events list and select Scroll up (Shift). Avoid Scroll up (Ctrl) because **Ctrl** is yet used by tools to turn to the Color Picker mode. Click on the Edit button to open a window that allows you to assign an action to the selected event. If an action is assigned to the event yet, the window opens on this event; else, click on the small triangular button close to the Context item to drop the list down. Scroll through this list and select the context-brush-radius-increase item. (You could choose context-brush-radius-increase-skip). Click on OK. Do the same way to assign the “context-brush-radius-decrease” action to the “Scroll down (Shift)” event to decrease the brush size. Save your brush by clicking on the Save button in the Brush Editor. Now, if you have selected your Dynamic brush, when you work with a tool that has a “Brush” option while pressing the **Shift** key, the brush size will vary by using the mouse wheel. This change will be visible in real time in the brush area of the Toolbox and in the Brush Dialog. By enabling the “Main Keyboard” tab, you can, in the same way, assign an action to the events of the keyboard arrow keys.