742081 - WebGL texture load broken does not work after bug 740841

Status: NEW

(Core :: ImageLib, defect)

Description

[Oleg Romashin (:romaxa)]

I see that webgl stopped working after landing fix from bug 740841
we always return with error on this condition:
http://hg.mozilla.org/mozilla-central/annotate/d698e656b1e0/image/src/RasterImage.cpp#l893
because mDecoder is not null

Comment 1

[Oleg Romashin (:romaxa)]

Attachment: Workaround which make it works back

Comment 2

[Timothy Nikkel (:tnikkel)]

So if we are asked to decode with different flags and we have a decoder already then should we shutdown the existing decoder and start a new one with the requested flags?

Comment 3

[Timothy Nikkel (:tnikkel)]

I backed out bug 740841 for now.

Comment 4

[Timothy Nikkel (:tnikkel)]

Attachment: fix?

Something like this seems to fix it. But I didn't do my homework on imglib to see if this is 100% kosher.

Comment 5

[Timothy Nikkel (:tnikkel)]

Testcase that I'm using for testing that I got from Oleg: http://www.everyday3d.com/j3d/demo/004_Glass.html

Comment 6

[Oleg Romashin (:romaxa)]

Comment on attachment 612124 [details] [diff] [review]
fix?

this works fine for me too

Comment 7

[Oleg Romashin (:romaxa)]

Comment on attachment 612124 [details] [diff] [review]
fix?

oh, no, tested it carefully, and found that textures now corrupted on half... sounds like we interrupting decoding and getting broken texture at the end

Comment 8

[Timothy Nikkel (:tnikkel)]

Sadly that makes sense. If there is a decoder already that means there is probably another consumer around of the same image but who wants different decode flags.

Comment 9

[Joe Drew (not getting mail)]

If we're already doing an asynchronous decode, and we want to do a synchronous decode for a different pixel format, we are in for a real heap of trouble, since the other decoders are waiting on notifications from the decode.

If we have all of the image data, we're OK: we can flush all the data to the decoder synchronously, shut it down, and then open a new decoder for the new format.

If we don't have all the image data, we should just refuse to fulfill the request.

Comment 10

[Boris Zbarsky [PTO through Aug 25, :bzbarsky, bz on IRC]]

If we don't have all the data, I'd think the webgl code should not be asking for it to start with.  Certainly 2d canvas is supposed to silently do nothing when asked to draw a still-loading image.