CodeEditApp
✨ Cursor Customization
Description
We should allow the user to customize their cursor both in the editor and in the terminal.
These customizations include:
- Cursor shape
- Bar
- Underline
- Block
- Cursor thickness (if shape is Bar or Underline)
- Rounded corners
- Cursor color (active and inactive)
- Accent Color
- Neutral
- Cursor transition between positions
- Cursor blink style
- Blink
- Smooth
- Phase
- Expand
- Solid (no blinking)
The blink styles seen in VS Code are:
| Style | Preview |
|---|---|
| Blink |  |
| Smooth | |
| Phase |  |
| Expand |  |
| Solid |  |
We might experiment to offer other variations of these (maybe phase+expand for example).
I’d imagine there are many possible ways this can be configured. We might provide the following configurations, we could even use these configurations internally to create presets and then allow the user to add a custom style by playing with these values shown below.
| Configuration | Default (Blink) | Smooth | Phase | Expand | Solid |
|---|---|---|---|---|---|
| blink on duration | 0.5s | 0.5s | 0.5s | 0.5s | 0.5s |
| blink off duration | 0.5s | 0.5s | 0.5s | 0.5s | 0.5s |
| transition in duration | 0s | 0.05s | 0.2s | 0.2s | 0s |
| transition out duration | 0s | 0.05s | 0.2s | 0.2s | 0s |
| opacity at on state | 1 | 1 | 1 | 1 | 1 |
| opacity at off state | 0 | 0 | 0 | 0 | 1 |
| vertical scale at on state | 1 | 1 | 1 | 1 | 1 |
| vertical scale at off state | 1 | 1 | 1 | 0 | 1 |
| horizontal scale at on state | 1 | 1 | 1 | 1 | 1 |
| horizontal scale at off state | 1 | 1 | 1 | 1 | 1 |
@CodeEditApp/maintainers What are your thoughts around this?
Considerations
This applies to both our editor which uses STTextView and the terminal which uses SwiftTerm. I've created this discussion in SwiftTerm to discuss how this might be done in coordination with their project.
From the discussion in SwiftTerm by @migueldeicaza:
You could make it so that the CaretView is not just an empty box, but one that fetches the current character and draws the current character as expected. This is slightly complicated due to type setting issues (you would need to either keep the CTRun cached, or you would need to compute the CTRun for it). This has the advantage that if properly done, it would work on iOS and macOS. This might have an ugly performance hit due to having to compute the layout for every cursor movement.
This might allow for us to make the experience consistent between the editor and terminal, but we would need to consider the performance implications this might have.
I just spoke with Marcin about this, he said the blinker layer is customizable with this entry point.
Go ahead and add me to this issue, I'll look at that entry point for the editor and then as we learn more about both I'll implement what we can.
I wonder if we can somehow share this custom cursor view between CodeEditTextView and our terminal view or if it would be better to implement them separately.
It might be possible, I was going to take a look at the cursor in CodeEditTextView this week and see what we could do to keep them consistent