Non-transparent command line when multigrid is enabled

[AckslD]

Describe the bug
When using --multigrid the command line is for some reason not transparent. See screenshot below which shows to equivalent instances where the only difference is that the left uses multigrid.

To Reproduce
Steps to reproduce the behavior:

1. Open neovide with multigrid.
2. Do :highlight MsgArea guifg=#ffffff guibg=none
3. See that the command line is black instead of transparent.

Expected behavior
Transparent command line.

Screenshots

Desktop (please complete the following information):

• OS: arch linux 5.19.3-arch1-1
• Neovide Version 0.10.1
• Neovim Version v0.8.0-dev-938-g3b2121cedf

Additional
Possibly related to #1387

[Pangoraw]

Since #1199, it seems you need to explicitely set the winblend and pumblend options.

[MultisampledNight]

Unrelated, unfortunately. Even with :set winblend=60 pumblend=60 this is reproducable.

[falcucci]

this issue still exists.

// grid_renderer.rs

if is_floating {
    self.paint
        .set_alpha((255.0 * ((100 - style.blend) as f32 / 100.0)) as u8);
} else if (SETTINGS.get::<WindowSettings>().transparency - 1.0).abs() > f32::EPSILON
    // Only make background color transparent
    && self.paint.color() == self.get_default_background()
{
    self.paint.set_alpha(0);
}

probably the logic must be updated here.

i'll check it when I have some time.

#1819

[fredizzimo]

With #1870, you can control the transparency of the commandline with the highlight group blend. And g:neovide_transparency also affects the command line.

But unfortunately, that is not enough, since you can't set blend for the default background it only affects floating windows(which the commandline technically is, see the blend documentation https://neovim.io/doc/user/syntax.html#%3Ahighlight. None as a workaround does also not work, since, none is specified as the default color, not transparent by the UI documentation https://neovim.io/doc/user/ui.html

So, we need this fix neovim/neovim#24472.

[falcucci]

@fredizzimo thank you. that's a well made explanation.

I guess this also impacts the treesitter highlight, which would be also amazing to fix.

look to the green grid highlighted bellow. It should always have 1.0 as opacity.

CleanShot.2024-01-17.at.18.24.12.mp4

[fredizzimo]

I created a proposal for dealing with global transparency

• [RFC] Proposal: handling of global transparency #2471