1440905 - (ImpressJS) broken rendering on ImpressJS

Status: RESOLVED WORKSFORME

(Core :: Graphics: WebRender, defect, P3)

Description

[John]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:60.0) Gecko/20100101 Firefox/60.0
Build ID: 20180223154206

Steps to reproduce:

Open https://impress.js.org and go through the presentation on both chrome and Firefox


Actual results:

The presentation was very junky, slow and unresponsive. I tried on Ubuntu 17.10 with both Firefox 58 with default settings and on Firefox 60 with acceleration and webrender enabled. The latter was improved but still not on par with chrome


Expected results:

The presentation should have been buttery smooth (using chrome as a reference here). This can actually be used as a future test for the browser and something QuantumFlow initiative could look into to find the cause

Comment 1

[John]

I would like to confirm that now on Nightly 61 the presentation is much smoother so good job!! However there is a bug with rendering in 3D as can be seen on https://impress.js.org/#/one-more-thing. The 3 text appears broken and not on a straight line as it does without webrender being enabled or on chrome.

Comment 2

[John]

A second bug on this presentation on webrender is when transitioning from https://impress.js.org/#/big to https://impress.js.org/#/tiny. There is some graphics glitch that is not present normally on chrome or firefox (no webrender)

Comment 3

[Jeff Muizelaar [:jrmuizel]]

Is it possible to get a video of the graphic glitch? I don't see it localy.

Comment 4

[Aria Beingessner [:Gankra]]

On windows (hidpi) I see the text randomly pop out as it gets bigger, likely hitting webrenders limit on font size.

On linux (1080p) the text instead gets blurry (so not being scaled artifically) but has weird clipping at the top.

Seems mildly important to fix, but not for the first release. (I expect other browsers do ~ok here because they fall into a "draw it like an SVG" path for large text.

Comment 5

[John]

Attachment: impress-js-presentation-2018-10-07_16.31.11

The video of the whole presentation on my computer. You can see is junky at places and the 3D content is not rendered properly

Comment 6

[John]

(In reply to Jeff Muizelaar [:jrmuizel] from comment #3)
> Is it possible to get a video of the graphic glitch? I don't see it localy.

I have attached the relevant video related to this bug. Hope it proves useful :)

Comment 7

[Glenn Watson [:gw]]

Seems to run well now.