Reapply "implement wayland fractional scaling"

[stacyharper]

This reverts commit 943d74600eb3791f3fe8344a844e5bc6d17899bb.

This fix the BEMENU_SCALE that was left unused when fractionnal scale support was detected.

This is rebased over origin/master.

[Cloudef]

FYI I separated BEMENU_SCALE from wayland buffer scale in this commit https://github.com/Cloudef/bemenu/commit/3156dac7d4cb94e323ca08087aacb15824a901c7 they aren't the same thing as compositor will render forced 2x buffers downscaled for example if your output is scale 1. BEMENU_SCALE should always give scaled buffer and window size (override). Forcing wayland buffer scale doesn't seem to ever make sense to me.

[stacyharper]

FYI I separated BEMENU_SCALE from wayland buffer scale in this commit 3156dac they aren't the same thing as compositor will render forced 2x buffers downscaled for example if your output is scale 1. BEMENU_SCALE should always give scaled buffer and window size (override). Forcing wayland buffer scale doesn't seem to ever make sense to me.

Perfect! Now I understand better BEMENU_SCALE, and it finaly also make sense to me.

I rebased this over your patch. And it seems to works as we expect it, with fractionnal support too.

One question I have. To preserve default BEMENU_SCALE, we have to use the output scale value (in my case BEMENU_SCALE=1.4). I would expect 1 would be the default, while 2 means "double dimensions".

[Cloudef]

Hmm, not sure I understand. BEMENU_SCALE has no default, so by default on X11 we use 1 (no scale), and on wayland whatever is output's scale.

What BEMENU_SCALE effectively does is:

• It creates buffer with multiplier of BEMENU_SCALE
• Passes BEMENU_SCALE to cairo
• Draws the buffer into a window that's equal of the buffer scale

This is the only way to do "hidpi" on X11 (I guess?) And on wayland this allows you to force hires buffers even on scale 1 outputs or if the output scale detection is wonky for whatever reason.

That said I haven't tried commit https://github.com/Cloudef/bemenu/commit/3156dac7d4cb94e323ca08087aacb15824a901c7 on outputs that are not 1x scale .. it may not work :thinking: Perhaps if BEMENU_SCALE is set, wl_buffer.scale should be set to 1 and we ignore window->scale (or we can force window->scale to always be 1)

[stacyharper]

That said I haven't tried commit https://github.com/Cloudef/bemenu/commit/3156dac7d4cb94e323ca08087aacb15824a901c7 on outputs that are not 1x scale .. it may not work 🤔

It works. But BEMENU_SCALE=1 doesn't give the "default". ex: output is 2x scale, you use BEMENU_SCALE=1, then bemenu is 2 time tinier than without the variable. The "default" in that situation is 2.0.

[Cloudef]

Yeah that might be slightly unexpected behavior, which I don't think is useful. I'll add commit that forces window->scale to 1 if BEMENU_SCALE is set. What do you think?

[stacyharper]

Yeah that might be slightly unexpected behavior, which I don't think is useful. I'll add commit that forces window->scale to 1 if BEMENU_SCALE is set.

No I don't think that is what we want. if you enforce window->scale=1 then the window will be blurry

[stacyharper]

I think what we want is this:

diff --git a/lib/renderers/wayland/window.c b/lib/renderers/wayland/window.c
index 0043c2b..cb3500e 100644
--- a/lib/renderers/wayland/window.c
+++ b/lib/renderers/wayland/window.c
@@ -149,7 +149,7 @@ create_buffer(struct wl_shm *shm, struct buffer *buffer, int32_t width, int32_t

     const char *env_scale = getenv("BEMENU_SCALE");
     if (env_scale) {
-        buffer->cairo.scale = fmax(strtof(env_scale, NULL), 1.0f);
+        buffer->cairo.scale = scale * fmax(strtof(env_scale, NULL), 1.0f);
     } else {
         buffer->cairo.scale = scale;
     }

[Cloudef]

Is it blurry even if you do BEMENU_SCALE=2 on output with scale 2? Shouldn't that effectively be same as wl_buffer with scale 2? I'd like to keep the value absolute scale if possible, as in you don't normally use it, but when you do you want it to exactly give the scale you request for.

[stacyharper]

Why someone would want to have a blurry or sharped surface? You can not enforce a hires surface with an output 1x scaled.

The current state, with the diff I gave earlier, seems ideal to me. Even with an 1x output, the user could enforce larger text and dimensions with BEMENU_SCALE=2.

[Cloudef]

Like I said, you normally do not use the env variable. But if you do, you want it to give the exact scale you request for. If you ask 1x scale on 2x output, you shall receive it. It's still possible to do relative scale by doing the math and inputting the result to BEMENU_SCALE.

[stacyharper]

Like I said, you normally do not use the env variable. But if you do, you want it to give the exact scale you request for. If you ask 1x scale on 2x output, you shall receive it. It's still possible to do relative scale by doing the math and inputting the result to BEMENU_SCALE.

I see what you mean. With output scale 1, or 2, using BEMENU_SCALE=1 gives a similar situation.

Why not! Both suits me. I never used this anyway :3

edit: then no change is required right? this is the current situation

[Cloudef]

No change needed. I add the scale = 1 scenario separately.

[Cloudef]

Merged, thanks!

[Cloudef]

This seems to fail in hyprland currently. I think this is bug in hyprland though.

[3013176.290]  -> wp_fractional_scale_manager_v1@9.get_fractional_scale(new id wp_fractional_scale_v1@18, wl_surface@17)
[3013176.293]  -> wp_viewporter@6.get_viewport(new id wp_viewport@19, wl_surface@17)
[3013176.296]  -> zwlr_layer_shell_v1@8.get_layer_surface(new id zwlr_layer_surface_v1@20, wl_surface@17, nil, 3, "menu")
[3013176.299]  -> zwlr_layer_surface_v1@20.set_anchor(13)
[3013176.302]  -> zwlr_layer_surface_v1@20.set_size(0, 32)
[3013176.305]  -> wl_surface@17.commit()
[3013176.307]  -> wl_display@1.sync(new id wl_callback@21)
[3013176.334] wl_display@1.delete_id(16)
[3013176.336] wl_display@1.delete_id(3)
[3013176.338] wl_display@1.error(wp_fractional_scale_manager_v1@9, 0, "Fractional scale exists.")
wp_fractional_scale_manager_v1@9: error 0: Fractional scale exists.

The compositor says the surface already has fractional scaling, but it does not, it was applied to different surface. I'll make this feature under BEMENU_WL_FRACTIONAL_SCALING env variable for now.

[stacyharper]

@Cloudef I don't understand aac7d73afcbd34f1662e994d235d9ee0eb98065a. This make the surface blurry all the time. What's the point of this?

[Cloudef]

Like I said, you normally do not use the env variable. But if you do, you want it to give the exact scale you request for. If you ask 1x scale on 2x output, you shall receive it. It's still possible to do relative scale by doing the math and inputting the result to BEMENU_SCALE.

Note it only forces scale = 1 if you use BEMENU_SCALE

[stacyharper]

Note it only forces scale = 1 if you use BEMENU_SCALE

Who would use this? What is the use case?

[Cloudef]

1. Test bemenu scaled cairo drawing bypassing any other scaling mechanism
2. Allow people to scale bemenu output to whatever scale, even if you don't have hidpi display
3. So that the behavior aligns what BEMENU_SCALE says in the manpage / readme and what it does on x11

[Cloudef]

Hmm, I just realized the compositor will in this case resize the surface 2x on 2x output...? .. So the original behavior without that commit would be the correct behavior.

EDIT: reverted the commit and made new release ...

[stacyharper]

Hmm, I just realized the compositor will in this case resize the surface 2x on 2x output...? .. So the original behavior without that commit would be the correct behavior.

Yes, on output scaled x2, the compositor upscale it itself, which cause a blurry surface. Without that commit, BEMENU_SCALE give control over the scaling, while staying pixel perfect for the compositor.

[Cloudef]

FYI, I opened issue here https://github.com/hyprwm/Hyprland/issues/4600