Allow customizing (and animating) the text cursor appearance

[eugenesvk]

Is your feature request related to a problem? Please describe.

I like the Bar cursor style instead of the Block one, but it's a bit too narrow, so visibility suffers more than it should

Describe the solution you'd like

A configuration option that would allow me to change the width of a Bar cursor

Describe alternatives you've considered
Going back to the Block

Additional context

[wez]

I'm not excited to add a very specific configuration option for this, because I think it would, over time as more options are added, make the implementation more complex and harder to change without breaking someone's carefully crafted config on an upgrade.

I've been considering exposing the custom block glyph styling datatypes to lua to allow for defining frames in animated cursors and I think that same mechanism could be used here for this; while it is a more complex configuration than just adding a width control, the overall result would simplify the logic for selecting a cursor shape and make a very powerful configuration for end users.

I don't know exactly what this would look like yet, but the general requirements are:

• Ability to override the possible cursor shapes individually. eg: do all of the below one way for SteadyBlock and a different way for SteadyBar and so on.
• Ability to specify either:
  • an image file to use for the shape
  • use the same set of drawing commands used for internal custom glyphs
• For animations:
  • If using animated gif/png then simply use those frames and timing info
  • Otherwise, ability to specify multiple frames (eg: discrete image files, or discrete drawing commands per frame), as well as the frame delay
• For inactive/unfocused display:
  • Specify a single frame to use
  • Consider adding a color scheme option for the inactive cursor color

[ghost]

OSC 22 is supported by several terminals for the application to select a cursor. I have not yet looked into it deeply, but apparently xterm and mintty at least do not agree on what those cursors should be.

If this feature is implemented, one might also get OSC 22 for nearly free.

[bertin0]

Consider adding a color scheme option for the inactive cursor color

So at the moment how is the inactive cursor color chosen? Is it hardcoded? Is it linked to any other color in the color scheme?

[wez]

There is currently no distinction for color based on the active pane. The shape does change to an outline shape when inactive.

[bertin0]

Sorry, I meant to say focus as in the window being clicked on or not. For me, in that case, the cursor hollows out and turns green instead of white/gray-ish as I set it in both cursor_fg and cursor_bg

[wez]

Look for cursor_border in https://wezfurlong.org/wezterm/config/appearance.html#defining-your-own-colors

[bertin0]

Look for cursor_border in https://wezfurlong.org/wezterm/config/appearance.html#defining-your-own-colors

Ah thanks that makes total sense, stupid me