Question about swapping modifiers

[jkroes]

Looking at the example layouts, I didn't see any that remapped modifiers. My intended use case was to swap command and control when switching between MacOS and Windows. Are swappable modifiers supported?

[kot149]

It should work for pure modifier key presses (like &kp LEFT_CONTROL) or mod-taps (like &mt LEFT_CONTROL A) with the following layout definition, but it doesn't work for modifiers applied to non-modifier key presses (like &kp LCTL(C)).
Additional implementation is required to support the latter one.

#ifdef CONFIG_LAYOUT_SHIFT_TARGET_SWAP_CTRL_CMD
#define LAYOUT_DEFINED
// Swap Ctrl and Cmd
static const struct keycode_mapping layout_map[] = {
    /* from -> to, optional_modifiers */
    {LEFT_CONTROL, LEFT_COMMAND, OPTIONAL_ALL},
    {LEFT_COMMAND, LEFT_CONTROL, OPTIONAL_ALL},
    {RIGHT_CONTROL, RIGHT_COMMAND, OPTIONAL_ALL},
    {RIGHT_COMMAND, RIGHT_CONTROL, OPTIONAL_ALL},
};
#endif

[kot149]

I've added the layout definition above so you can give it a try to see if it works for you.

zmk-layout-shift/src/layouts/layout_swap_ctrl_cmd.h

Lines 1 to 11 in f71c42d

	#ifdef CONFIG_LAYOUT_SHIFT_TARGET_SWAP_CTRL_CMD
	#define LAYOUT_DEFINED
	// Swap Ctrl and Cmd
	static const struct keycode_mapping layout_map[] = {
	/* from -> to, optional_modifiers */
	{LEFT_CONTROL, LEFT_COMMAND, OPTIONAL_ALL},
	{LEFT_COMMAND, LEFT_CONTROL, OPTIONAL_ALL},
	{RIGHT_CONTROL, RIGHT_COMMAND, OPTIONAL_ALL},
	{RIGHT_COMMAND, RIGHT_CONTROL, OPTIONAL_ALL},
	};
	#endif