Avoid to have a white line around the canvas

[calixteman]

No description provided.

[calixteman]

/botio-linux preview

[moz-tools-bot]

From: Bot.io (Linux m4)

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Live output at: http://54.241.84.105:8877/88217b30ad42bab/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Success

Full output at http://54.241.84.105:8877/88217b30ad42bab/output.txt

Total script time: 1.01 mins

Published

• Viewer: http://54.241.84.105:8877/88217b30ad42bab/web/viewer.html
• Viewer (legacy): http://54.241.84.105:8877/88217b30ad42bab/legacy/web/viewer.html

[nicolo-ribaudo]

This looks good to me, does it also still fix the "small movement when the canvas is redrawing" problem you mentioned?

[calixteman]

This looks good to me, does it also still fix the "small movement when the canvas is redrawing" problem you mentioned?

Yes it does for me, doesn't it for you ?

[Snuffleupagus]

Comparing https://mozilla.github.io/pdf.js/web/viewer.html and #18698 (comment) side-by-side, it does appear that this patch makes the canvas slightly blurry at some zoom levels (e.g. auto).

[calixteman]

/botio-linux preview

[moz-tools-bot]

From: Bot.io (Linux m4)

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[moz-tools-bot]

From: Bot.io (Linux m4)

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Full output at http://54.241.84.105:8877/9d05db1bb764359/output.txt

Total script time: 1.01 mins

Published

• Viewer: http://54.241.84.105:8877/9d05db1bb764359/web/viewer.html
• Viewer (legacy): http://54.241.84.105:8877/9d05db1bb764359/legacy/web/viewer.html

[Snuffleupagus]

The new preview still suffers from blurriness issues unfortunately; there doesn't seem to be any improvement there.

Are the src/display/display_utils.js changes perhaps enough to fix the regression as filed, because if so I believe that we should do that first and worry about the other parts of this PR later!?

[calixteman]

The new preview still suffers from blurriness issues unfortunately; there doesn't seem to be any improvement there.

Are the src/display/display_utils.js changes perhaps enough to fix the regression as filed, because if so I believe that we should do that first and worry about the other parts of this PR later!?

Unfortunately it isn't enough.
At 70%, the page dims are 555x785 when the canvas css dims are 554x784.

I can see some blurriness on a screen with window.devicePixelRatio === 1.5 too but only around a zoom level equals to 60-70% when the text becomes barely readable (at least for me). In changing in the css width & height to calc(100% - 1px), I can see an improvement but then we see the page background.
I tried the same with a screen where the ratio is 1 and there aren't that much differences.
I've the impress that the problem mainly something about font hinting and anti-aliasing.
Out of curiosity, I added image-rendering: pixelated; to the canvas style and it fixes the blurriness for me.

That said my feeling is that the patch by itself isn't really the problem but there's maybe something else on the gfx side.
I'll check how it behaves in Chrome later.

[Snuffleupagus]

I just realized that I wasn't clear before: The blurriness I'm talking about with this patch is with the default tracemonkey.pdf file and window.devicePixelRatio === 2, at e.g. the "auto" zoom level.
Hence this patch really doesn't seem acceptable as-is, most unfortunately.

[calixteman]

I think it's because the ratio between the canvas width/height and the canvas css width/height is no more exactly equal to 1.5 (my devicePixelRatio).
So I think, we should change the 3rd parameter of the round function in the css to have something which uses the denominator found by Farey approximation.
That said maybe having the right ratio helped to just use the right algorithm to downscale the canvas, so maybe (too much maybe in this sentence) using pixelated could be the right way to do it.

[calixteman]

@Snuffleupagus, what's the real zoom level, as a number, you use ?

[Snuffleupagus]

what's the real zoom level, as a number, you use ?

125 percent; as defined in

pdf.js/web/ui_utils.js

Line 22 in 77c7ec6

const MAX_AUTO_SCALE = 1.25;

[calixteman]

/botio-linux preview

[moz-tools-bot]

From: Bot.io (Linux m4)

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Command cmd_preview from @calixteman received. Current queue size: 0

Live output at: http://54.241.84.105:8877/1a16f65dd7ba6b1/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Success

Full output at http://54.241.84.105:8877/1a16f65dd7ba6b1/output.txt

Total script time: 1.01 mins

Published

• Viewer: http://54.241.84.105:8877/1a16f65dd7ba6b1/web/viewer.html
• Viewer (legacy): http://54.241.84.105:8877/1a16f65dd7ba6b1/legacy/web/viewer.html

[Snuffleupagus]

Testing with the tracemonkey.pdf file, this patch unfortunately still looks worse (for me) compared to master.

[calixteman]

What do you mean exactly by worse ?
Could you share a screenshot showing both rendering ?

[Snuffleupagus]

Here's two screen-shots, from master respectively the patch, where the letters are noticeably more blurry with this patch. (Comparing the images at high magnification might be helpful to see the differences more clearly.)

[nicolo-ribaudo]

The new preview still suffers from blurriness issues unfortunately; there doesn't seem to be any improvement there.
Are the src/display/display_utils.js changes perhaps enough to fix the regression as filed, because if so I believe that we should do that first and worry about the other parts of this PR later!?

Unfortunately it isn't enough. At 70%, the page dims are 555x785 when the canvas css dims are 554x784.

Is this with the test PDF? I'm seeing both as 555x785 🤔 (by using inspect element and changing those round() CSS functions at https://mozilla.github.io/pdf.js/web/viewer.html, with Firefox 130.0)

[calixteman]

FYI, the added integration test is correctly failing on master.

[calixteman]

/botio test

[moz-tools-bot]

From: Bot.io (Linux m4)

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[moz-tools-bot]

From: Bot.io (Windows)

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Command cmd_test from @calixteman received. Current queue size: 0

Live output at: http://54.193.163.58:8877/2d76cd3c497b2ab/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Failed

Full output at http://54.241.84.105:8877/6593269a41bf21a/output.txt

Total script time: 30.89 mins

• Unit tests: Passed
• Integration Tests: Passed
• Regression tests: FAILED

  different ref/snapshot: 163

Image differences available at: http://54.241.84.105:8877/6593269a41bf21a/reftest-analyzer.html#web=eq.log

[calixteman]

The small movements we've are very likely due to the change in the text (or annotation) layer dimensions where we now round differently (in passing --scale-round-x/y as third parameter).

[moz-tools-bot]

From: Bot.io (Windows)

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Failed

Full output at http://54.193.163.58:8877/2d76cd3c497b2ab/output.txt

Total script time: 46.01 mins

• Unit tests: Passed
• Integration Tests: FAILED
• Regression tests: FAILED

  different ref/snapshot: 77

Image differences available at: http://54.193.163.58:8877/2d76cd3c497b2ab/reftest-analyzer.html#web=eq.log

[calixteman]

/botio makeref

[moz-tools-bot]

From: Bot.io (Linux m4)

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Command cmd_makeref from @calixteman received. Current queue size: 0

Live output at: http://54.241.84.105:8877/5d01090de0eacc4/output.txt

[moz-tools-bot]

From: Bot.io (Windows)

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Command cmd_makeref from @calixteman received. Current queue size: 0

Live output at: http://54.193.163.58:8877/1788070cff34fc7/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Success

Full output at http://54.241.84.105:8877/5d01090de0eacc4/output.txt

Total script time: 20.28 mins

• Make references: Passed
• Check references: Passed

[moz-tools-bot]

From: Bot.io (Windows)

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Success

Full output at http://54.193.163.58:8877/1788070cff34fc7/output.txt

Total script time: 26.54 mins

• Make references: Passed
• Check references: Passed