Input Processor Overview
Input Processors Overview
"Input processors" are small pieces of functionality that process and optionally modify events generated from emulated and physical pointing devices. Processors can do things like scaling movement values to make them larger or smaller for detailed work, swapping the event types to turn movements into scroll events, or temporarily enabling an extra layer while the pointer is in use.
Usage
For information on using input processors with a given pointing device, see input processor usage.
Available Processors
Below is a summary of pre-defined input processors and user-definable input processors available in ZMK, with references to documentation pages describing them.
Pre-Defined Processors
A set of predefined input processors is available by adding the following at the top of your keymap/overlay file:
#include <input/processors.dtsi>
Once included, you can use the following:
| Binding | Processor | Description |
|---|---|---|
&zip_xy_scaler | XY Scaler | Scale a the X/Y input events using a multiplier and divisor |
&zip_x_scaler | X Scaler | Scale a the X input events using a multiplier and divisor |
&zip_y_scaler | Y Scaler | Scale a the Y input events using a multiplier and divisor |
&zip_xy_transform | XY Transform | Transform X/Y values, e.g. inverting or swapping |
&zip_scroll_transform | Scroll Transform | Transform wheel/horizontal wheel values, e.g. inverting or swapping |
&zip_xy_to_scroll_mapper | XY To Scroll Mapper | Map X/Y values to scroll wheel/horizontal wheel events |
&zip_xy_swap_mapper | XY Swap Mapper | Swap X/Y values |
&zip_temp_layer | Temporary Layer | Temporarily enable a layer during pointer use |
&zip_button_behaviors | Mouse Button Behaviors | Trigger behaviors when certain mouse buttons are pressed |
User-Defined Processors
Several of the input processors that have predefined instances, e.g. &zip_xy_scaler or &zip_xy_to_scroll_mapper can also have new instances created with custom properties around which input codes to scale, or which codes to map, etc.
| Compatible | Processor | Description |
|---|---|---|
zmk,input-processor-transform | Transform | Perform various transforms like inverting values |
zmk,input-processor-code-mapper | Code Mapper | Map one event code to another type |
zmk,input-processor-behaviors | Behaviors | Trigger behaviors for certain matching input events |
External Processors
Much like behaviors, custom input processors can also be added to external modules to allow complete control of the processing operation. See input_processor.h for the definition of the driver API.