Text alignment issue in arcade 3

[bunny-therapist]

Bug Report

System Info

Arcade 3.0.0.dev24
------------------
vendor: Intel
renderer: Intel(R) UHD Graphics
version: (3, 3)
python: 3.11.0 (main, Oct 24 2022, 18:26:48) [MSC v.1933 64 bit (AMD64)]
platform: win32
pyglet version: 2.0.8
PIL version: 9.4.0

Actual behavior:

arcade.Text objects with align="center" are not center aligned (the multiline kwarg seems to also influence this; at least sometimes the text becomes aligned by setting multiline=True). It looks fine in arcade 2.6.17 but not in 3.0.0.dev24.

Expected behavior:

Text that was center aligned in 2.6.17 should still be in the same position when upgrading to arcade 3.0.0.

Steps to reproduce/example code:

Run this code with arcade==2.6.17 - the text is in the middle of the window. Run this code with arcade==3.0.0.dev24 - the text is off to the right.

import arcade


class IssueDemonstrationWindow(arcade.Window):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.text = arcade.Text(
            text="MIDDLE",
            start_x=400,
            start_y=300,
            font_size=72,
            width=800,
            anchor_x="center",
            align="center",
        )
        self.set_viewport(
            left=0,
            right=800,
            bottom=0,
            top=600,
        )

    def on_draw(self):
        self.text.draw_debug()


window = IssueDemonstrationWindow()
arcade.run()

[bunny-therapist]

It seems like the problem disappears if you remove the "width" argument.

[gran4]

The text fits into the box if you comment out anchor_x="center", But, the box is not in the middle if you do that.

[gran4]

I think I found the issue. If you increase the width, it moves the text even more: This is because line 1411 in layout.py in pyglet return self._x - width // 2

layout.TextLayout inside DocumentLabel inside pyglet.text.Label

P.S: I will make an issue in pyglet.

[gran4]

According to caffinepills, it is not a bug, it is intended.

[bunny-therapist]

Why did it change in arcade between 2.6.17 and 3? If this is due to a change in pyglet version, does that mean that pyglet intended for this to change?

[bunny-therapist]

I just tried arcade 2.6.17 with both pyglet 2.0.dev23 (which 2.6.17 uses) and 2.0.9 (which arcade 3 uses) and the text alignment problem does not occur.

It seems like arcade 2.6.17 had two lines in arcade.Text which set multiline=True if align != "left". These were removed, causing the issue.

[bunny-therapist]

This PR deleted those lines: https://github.com/pythonarcade/arcade/pull/1631/files#diff-9140ff68bfb252a17ae75c25ab36187e2b25beae54a64cfe4030d4e960ada6f9

Merge commit: https://github.com/pythonarcade/arcade/commit/e143b671398e22d5c8d981abb49c17b4776412cd#diff-9140ff68bfb252a17ae75c25ab36187e2b25beae54a64cfe4030d4e960ada6f9L193

[pushfoo]

Since the PR which deleted the lines was UI-related, does adding the lines back break anything UI-related?

[gran4]

Since the PR which deleted the lines was UI-related, does adding the lines back break anything UI-related?

It seems to have been related to this commit, look at the title of it: cc5b1b9fec138099dc190d69135bd853f024c5da

[bunny-therapist]

If the intention is to make arcade.Text have the same interface as pyglet text functionality, without any special multiline modification, I am fine with it as long as it happens as part of the major version bump to arcade 3. (I am a bit concerned about the fact that there seems to be little awareness of this change having happened.)

[pushfoo]

as long as it happens as part of the major version bump to arcade 3

As far as I understand, 2.6.X isn't expected to have any further updates.

[bunny-therapist]

Yeah, so whether to put those two lines back or not should be decided upon before the release of arcade 3.

[eruvanos]

Hi, I would like to revive this discussion and come to a fix.

From my point of view, from the UI I need to be able to have align="center" and multiline=False. (At least what I know right now, based on the fact, that a width is often given during the do_layout phase of the UI, but not during creation).

But I think I can use some workaround for that on the GUI side.

Which would lead to the question, if a dev sets multiline=False and align="center" does it make sense to just overwrite the multiline?

From the pyglet docs:

align: Horizontal alignment of text on a line, only applies if a width is supplied. One of `"left"`, `"center"` or `"right"`.

Which basically says that it would be fine to not set width and align!="left", it just has no effect until a width is set.

[eruvanos]

We changed the arcade.text code for 3.X. #2000 removes the mixed behaviour to:

align does not interfere with multiline (which was the case before)