This module is used to quantize X and Y value set to fit inside single payload of pointing device on split peripheral, to reduce the bluetooth connection loading between the peripherals and the central.
It packs both X and Y axis value set (two int16_t) from pointing device driver into one uint32_t (as Z axis value code) on split peripheral. Only 8 byte will be transmitted, and then resurrected back into two new X/Y input events on central side. Roughly, shall save up to 50% packet size for one 2D coordination. The compression and decompression are handled in two predefined input prcessor config, &zip_xyz & &zip_zxy. They should be placed at the ends of chain of processors between central and peripheral.
Include this module on your ZMK's west manifest in config/west.yml:
manifest:
remotes:
#...
# START #####
- name: badjeff
url-base: https://github.com/badjeff
# END #######
#...
projects:
#...
# START #####
- name: zmk-input-processor-xyz
remote: badjeff
revision: main
# END #######
#...Roughly, overlay of the split-peripheral trackball should look like below.
/* Typical common split inputs node on central and peripheral(s) */
/{
split_inputs {
#address-cells = <1>;
#size-cells = <0>;
trackball_split: trackball@0 {
compatible = "zmk,input-split";
reg = <0>;
};
};
};
/* Add the compressor (zip_xyz) on peripheral(s) overlay */
#include <input/processors/xyz.dtsi>
&trackball_split {
device = <&trackball>;
/* append XY-to-Z compressor on transmitting side */
input-processors = <&zip_xyz>;
};
/* Add the decompressor (zip_zxy) on central overlay */
#include <input/processors/xyz.dtsi>
tball1_mmv_il {
compatible = "zmk,input-listener";
device = <&trackball_split>;
/* preppend Z-to-XY processor on receiving side */
input-processors = <&zip_zxy>, <&zip_report_rate_limit 8>;
/* NOTE: &zip_report_rate_limit is avaliable at https://github.com/badjeff/zmk-input-processor-report-rate-limit */
};