### 3.2.2. Interacting with modules

A module has an expander bar . Clicking on the name of the module expands the module's GUI with all parameters.

In its default setting darktable will only expand one GUI at a time. If you click the expander bar of another module, the previous GUI gets collapsed. If you want to see more than one GUI expanded, you may expand further modules with shift-click  – all previously expanded GUIs remain opened. The expander bar behavior on click and shift-click, respectively, is controlled by a preference setting in GUI options (see Section 8.1, “GUI options”).

Expanding a module does not activate it. You need to click the icon to turn a module on or off.

Icon accesses the module's available presets or creates a new preset from your current settings (see Section 3.2.3, “Module presets”).

The icon is used to reset the module parameters to their default values.

Many of darktable's modules can have multiple instances, each with different settings. Click on the icon to generate new instances and control existing ones (see Section 3.2.4, “Multiple instances”).

The most frequently used control elements of modules are sliders, comboboxes and curves.

#### 3.2.2.1. Sliders

Sliders offer five different ways of interaction, depending on the level of control you need.

1. Triangular marker

Left-click the slider's triangular marker and drag it to the left or right.

2. Mouse wheel

Hover over any place on the slider with your mouse, then use your mouse wheel to adjust the value step by step.

3. Keyboard arrow keys

Hover over any place on the slider with your mouse, then use your keyboard's arrow keys (←/↓ and →/↑) to adjust the value stepwise.

4. Right-click

When your mouse is over a slider right-click gives you a multi-functional pop-up below the slider for fine control with your mouse or numerical entry using the keyboard.

darktable's innovative input method: for both coarse and fine value adjustments in a single control element combined with keyboard input.

A bent line extending from the triangular marker moves as you move your mouse. The closer your mouse pointer is to the triangular marker the coarser the control; the further away from the triangular marker the finer is your control. Left-click with your mouse to accept the new value and go back to normal control.

Alternatively you can type in a new value using your keyboard and commit by hitting the enter key. You may even supply the new value in the form of an arithmetic expressions which darktable will calculate for you – the old value is referenced as x.

5. Double-click

You can double-click on a parameter label to reset its value to default.

Additionally, the mouse wheel and keyboard arrow keys support two input modifiers:

• You can hold down the shift key increasing the stepsize by a factor of 10. You can change this multiplier:

darkroom/ui/scale_rough_step_multiplier=10.0


• You can hold ctrl key decreasing the stepsize by a factor of 10. You can change this multiplier:

darkroom/ui/scale_precise_step_multiplier=0.1


#### 3.2.2.2. Comboboxes

Clicking on a combobox will open a list of available options. Click on the item you want to select. Sometimes the selection list opens close to the bottom or top of the screen and only part of the items are visible; scroll with your mouse wheel to bring up the full list. Alternatively, you can also use the mouse wheel and keyboard arrow keys to select an option.

#### 3.2.2.3. Curves

Some modules are controlled by adjusting curves. More detail is given later in this chapter when the respective modules are explained.

#### 3.2.2.4. Undo/redo

During editing darktable records all changes made in the history (see Section 3.3.3, “History stack”). This includes modifications of any parameter in a module itself but also if a module instance is added or removed. Thanks to this recording it is possible to undo changes or redo them to recover a previous editing state. Note that this undo/redo facility is unlimited in the number of steps while editing an image but it is reset each time the darkroom is switched to a new image.

The default key shortcuts are:

• Ctrl-z : undo last history modification

• Ctrl-y : redo last undo (does nothing if undo has not been used yet)

Please note that changes to drawn masks (see Section 3.2.7, “Drawn mask”) are not recorded and thus cannot be undone.