Transparent GIFs rendered incorrectly

[Jenyyk]

GIF frames are never disposed while playing, so if they arent overwritten, they stay on screen. This is a problem when you try to play transparent GIFs.

I am playing this GIF with viu:

and after a couple seconds of playing, the terminal looks like this:

The issue is that the transparent pixels show the previous frames of the GIF, which are not being deleted.
I am using the ghostty terminal emulator with the kitty protocol. I have not tested this with iTerm.

[Jenyyk]

So I have found a way to fix this for block mode by just filling the terminal with spaces, fix here. Fixing this for kitty graphics is another thing entirely, as they take too long to render to just clear and replace, which causes flashing of the gif. This seems to be a core issue with how viu renders gifs with kitty, as it doesnt actually render a gif, but renders the images one after the other.

If anyone is interested in getting kitty working, the function i used (that caused flashing) is here:

use std::io{self, Write};
fn clear_kitty_image() -> io::Result<()> {
    // Escape sequence to delete all visible images
    let sequence = "\x1b_Ga=d\x1b\\";

    io::stdout().write_all(sequence.as_bytes())?;
    io::stdout().flush()?;

    Ok(())
}