Incorrect cursor position after drawing image (iTerm inline image protocol)

[o2sh]

Describe the bug

While adding support for iTerm inline image protocol to onefetch, we stumbled upon an inconsistent behavior between iTerm2 and WezTerm.

iTerm2:

WezTerm:

The cursor position after drawing the image is at the bottom left hand corner (WezTerm) instead of near the lower right corner (iTerm2).

Indeed - after drawing the image -, if we do this

image_data.extend(format!("\x1B[{}A", image_rows as u32).as_bytes()); // move cursor to top-left corner
image_data.extend(format!("\x1B[{}C", image_columns as u32 + 1).as_bytes()); // move cursor to top-right corner of image

instead of that

image_data.extend(format!("\x1B[{}A", image_rows as u32 - 1).as_bytes()); // move cursor to start of image`

We get the correct output:

However, this obviously breaks the output on iTerm2...

Environment (please complete the following information):

• OS: macOS
• Version: wezterm 20200909-002054-4c9af461

Expected behavior

Consistent behavior with iTerm2 which is the de-facto standard.

[wez]

Thanks for reporting this! I've pushed a fix that seems to make the onefetch sixel and iterm2 backend behavior consistent with each other within wezterm, and consistently with sixel in xterm.

That'll be available in the "nightly" downloads within about an hour.

[o2sh]

Well done!

[github-actions]

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