728482 - [webgl] Textures created from PNGs are sometimes getting alpha premultiplied

Status: UNCONFIRMED

(Core :: Graphics, defect)

Description

[conor]

Attachment: pngerror.jpg

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:9.0.1) Gecko/20100101 Firefox/9.0.1
Build ID: 20111220165912

Steps to reproduce:

Run this test app:
http://www.railgun3d.com:8080/gltest4/demo.htm



Actual results:

Occasionally the texture for the grey texture will load in black where the alpha channel is low values (premultiplying the alpha).  This usually happens the first time after restarting Firefox, but not always.  It normally does not occur after a page refresh.  The top image in the attached picture shows the incorrect state.

One thing to note is that I could not reproduce this if the images are transferred unzipped; as soon as I added back in the gzip content encoding it started breaking again.



Expected results:

The textures should always load in consistently without premultiplying the alpha channel.

Comment 1

[Bill Baxter]

Maybe same as Bug 698169?

Comment 2

[Kelsey Gilbert [:jgilbert]]

If this cannot be reproduced, it was likely fixed as part of bug 696569.