On-release option for positional-hold-taps

[urob]

This fixes #1363 by adding a hold-trigger-on-release option to positional hold-taps.

When hold-trigger-on-release is set to true, it delays the evaluation of hold-trigger-key-position until the next key's release. This is in contrast to the current behavior, which evaluates hold-trigger-key-positions upon the next key press. The current behavior is not always ideal, for example for homerow mods, because it prevents combining multiple modifiers on the same hand.

The new hold-trigger-on-release configuration allows combining multiple modifiers when held, while still forcing a tap-decision when the next key is tapped.

Note: Due to the delay of the position-check until key release, the property has no effect when using the hold-preferred flavor (which triggers mods when another key is pressed). The property is most useful when combined with the balanced or tap-preferred flavor.

Example configuration:

// 36 keys layout
#define LEFT_KEYS 0 1 2 3 4 10 11 12 13 14 20 21 22 23 24  // left-hand keys
#define RIGHT_KEYS 5 6 7 8 9 15 16 17 18 19 25 26 27 28 29  // right-hand keys

/ {
    behaviors {
        hrm_l: left_homerow_mods {
            compatible = "zmk,behavior-hold-tap";
            label = "HOMEROW_MODS_LEFT";
            #binding-cells = <2>;
            flavor = "balanced";
            tapping-term-ms = <200>;
            hold-trigger-key-positions = <RIGHT_KEYS>;
            hold-trigger-on-release;
            bindings = <&kp>, <&kp>;
        };

        hrm_r: right_homerow_mods {
            compatible = "zmk,behavior-hold-tap";
            label = "HOMEROW_MODS_RIGHT";
            #binding-cells = <2>;
            flavor = "balanced";
            tapping-term-ms = <200>;
            hold-trigger-key-positions = <LEFT_KEYS>;
            hold-trigger-on-release;
            bindings = <&kp>, <&kp>;
        };
    };
};

[jigfox]

Tank you for trying to solve the problem with chording mods and using hold-trigger-key-positions together. But sadly it isn't working for me. If I roll over 21 &rhm LALT I and 20 &rhm LGUI E, so a very fast 21 down, 20 down, 21 up, 20 up. The keyboard fires alt-e, but I want to get the letters ie. Although e (key 20) is not part of hold-trigger-key-positions in &rhm

Same goes for rolling 20 and 19, there I get an E instead en.

/ {
  behaviors {
    // 0   1   2   3   4   5                    6   7   8   9   10  11
    // 12  13  14  15  16  17                   18  19  20  21  22  23
    // 24  25  26  27  28  29  30  31   32  33  34  35  36  37  38  39
    //             40  41  42  43  44   45  46  47  48  49
    rhm: right_home_row_mod {
      compatible = "zmk,behavior-hold-tap";
      label = "RIGH_POSITIONAL_HOLD_TAP";
      #binding-cells = <2>;
      tapping-term-ms = <200>;
      bindings = <&kp>, <&kp>;
      hold-trigger-key-positions = <0 1 2 3 4 5 12 13 14 15 16 17 24 25 26 27 28 29 30 31 40 41 42 43 44>;
      hold-trigger-on-release;
    };
    lhm: left_home_row_mod {
      compatible = "zmk,behavior-hold-tap";
      label = "LEFT_POSITIONAL_HOLD_TAP";
      #binding-cells = <2>;
      tapping-term-ms = <200>;
      bindings = <&kp>, <&kp>;
      hold-trigger-key-positions = <6 7 8 9 10 11 18 19 20 21 22 23 32 33 34 35 36 37 38 39 45 46 47 48 49>;
      hold-trigger-on-release;
    };
  };
  keymap {
    compatible = "zmk,keymap";

    default_layer {
      bindings = <
	&kp TAB        &kp Q          &kp W        &kp F          &kp P         &kp B                                                     &kp J     &kp L         &kp U        &kp Y        &kp SEMI      &kp BSPC
	&mt LCTRL ESC  &lhm  LCTRL A  &lhm LALT R  &lhm LGUI S    &lhm LSHFT T  &kp G                                                     &kp M     &rhm LSHFT N  &rhm LGUI E  &rhm LALT I  &rhm LCTRL O  &mt RCTRL SQT
	&kp LSHFT      &kp Z          &kp X        &kp C          &kp D         &kp V        &kp LBKT  &kp GRAVE   &caps_word  &kp RBKT   &kp K     &kp H         &kp COMMA    &kp DOT      &kp FSLH      &kp RSHFT
	                                           &kp LG(LSHFT)  &kp LCMD      &mt LALT RET &kp SPACE &mo NAV     &mo SYM     &kp SPACE  &kp RALT  &kp RGUI      &kp HYP
        >;
    };
  };
};

[urob]

Tank you for trying to solve the problem with chording mods and using hold-trigger-key-positions together. But sadly it isn't working for me. If I roll over 21 &rhm LALT I and 20 &rhm LGUI E, so a very fast 21 down, 20 down, 21 up, 20 up. The keyboard fires alt-e, but I want to get the letters ie. Although e (key 20) is not part of hold-trigger-key-positions in &rhm

Thanks for reporting. This is to be expected due to the default flavor being "hold-preferred", which triggers when another key has been pressed (bypassing the key-position check which is delayed until key release). I suggest using the "balanced" or "tap-preferred" flavor along with this feature.

[jigfox]

Thank you for your response, and thanks for your efforts, with balanced-flavor it is working now

[jigfox]

Working with this branch for one week now, and it is working perfectly fine

[caksoylar]

I have been using this branch for a few weeks now as well, no problems with it, I would love to see it merged. It fixes the major problem I had with positional hold-taps which is not being able to combine multiple holds on the same side.

[urob]

I have been using this branch for a few weeks now as well, no problems with it, I would love to see it merged. It fixes the major problem I had with positional hold-taps which is not being able to combine multiple holds on the same side.

Thanks! I have been using it as well without issues for quite a while now. @petejohanson from my side it's ready to be reviewed

[ifreund]

I'm using this commit in my zmk fork and this works great for the balanced flavor. The status quo hold-trigger-key-position behavior is unusable for me with the balanced flavor at least and I was very happy to discover this branch existed.

The approach taken by this commit is quite elegant and straightforward, it would be nice to see it merged someday.

[petejohanson]

One minor nitpick on the updated conditional. This also should have a new test added to assert the updated additional behavior option and it's functionality.

[petejohanson]

This can be simplified to undecided_hold_tap->config->hold_trigger_on_release != ev->state>

[urob]

good catch, done

[urob]

One minor nitpick on the updated conditional. This also should have a new test added to assert the updated additional behavior option and it's functionality.

Done. I have tests for all 3 main flavors but only committed the one for balanced so far since the flag is meaningless for the other ones. But if you prefer I can upload them as well.

[petejohanson]

@urob can you please rebase against latest main? Missed the netlify deploy failures earlier. Then I think this is ready to merge.

[urob]

@urob can you please rebase against latest main? Missed the netlify deploy failures earlier. Then I think this is ready to merge.

Done. I noted those netlify deploy failures but didn't know where they came from and what to do about (they weren't there when I first pushed this branch). But looks like they are resolved after the rebase.

[petejohanson]

Thanks!