177670 - Support dynamic MNGs

Status: RESOLVED WONTFIX

(Core :: Graphics: ImageLib, enhancement)

Description

[Hakon]

Are there any plans to support dynamic MNG's natively? Those could be used for
mouse-over effects and similar implementations...

Comment 1

[Jo Hermans]

Reporter, do you mean animated MNG's ? That's already supported : see
http://www.libpng.org/pub/mng/img_mng/pnglogo-grr-anim-lc.mng for a testcase.

Comment 2

[Christian :Biesinger (don't email me, ping me on IRC)]

-> tor

Comment 3

[tor]

Not high on my priority list - reassigning to nobody.

Comment 4

[Greg K.]

Dynamic MNG will be part of libmng 1.0.5, so adding dependency on bug 181676.

Comment 5

[Olivier Cahagne]

Does Mozilla need specific code to enable dynamic mng ? Are the nightly builds
done with the new libmng 1.05 (from bug 181676) ?
I just tried the example mentioned on http://www.libmng.com/dynamicMNG.html
using build 2003030908 on Win2k but they don't animate when I mouse over the
images or maps.

Comment 6

[Christian :Biesinger (don't email me, ping me on IRC)]

> Does Mozilla need specific code to enable dynamic mng ?

Yes. That code is not written yet.

Comment 7

[Christian :Biesinger (don't email me, ping me on IRC)]

this seems not too difficult to implement:
1. imgContainerMNG should implement nsIDOMMouseListener as well as
nsIDOMMouseMotionListener
2. find a way to get to the imgIContainer in nsImageFrame.cpp ::OnStopDecode
3. Try to QI it to aforementioned interfaces, if it succeeds, add code similar
to nsObjectFrame.cpp around line 3966

4. when the methods on nsIDOMMouse*Listener get called, do the appropriate mng
calls.

Comment 8

[Christian :Biesinger (don't email me, ping me on IRC)]

actually, in point 2), OnStartContainer is maybe better than OnStopDecode,
because people might want to interact with the image before it is fully loaded...

Comment 9

[Christian :Biesinger (don't email me, ping me on IRC)]

taking, I can fix this, I hope an additional QueryInterface per image load is
not too bad a thing.

Comment 10

[Christian :Biesinger (don't email me, ping me on IRC)]

let's be optimistic with the target milestone.

Comment 11

[Gerard Juyn]

> actually, in point 2), OnStartContainer is maybe better than OnStopDecode,
> because people might want to interact with the image before it is fully
> loaded...

Dynamic MNG's actually don't get dynamic until the entire stream is read, so
OnStopDecode would do for now. This is a design issue. The internal labels used
for dynamics precede the content, and it would crash jumping to one, if the
underlying image(s) aren't loaded yet. I still have to figure out a way around
that, but don't expect that any time soon. (yeah I know... a challenge... ;)

Comment 12

[Christian :Biesinger (don't email me, ping me on IRC)]

The advantage of OnStartContainer is that it easily has access to imgIContainer,
because it's a function argument :)

Comment 13

[Christian :Biesinger (don't email me, ping me on IRC)]

wow, do you believe that it is _not_ trivial to get the x/y position relative to
the corner of the image?

Comment 14

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

the form-submission code might be of help. It figures out the clicked x and y
position of the image.

http://lxr.mozilla.org/mozilla/source/content/html/content/src/nsHTMLInputElement.cpp#2269

Comment 15

[Christian :Biesinger (don't email me, ping me on IRC)]

sicking: thanks, that does help me!

Now... how do I get the coordinates to the image container...

Comment 16

[Hakon]

Since mng support has been lifted out of mozilla trunk, should this bug be closed?

Comment 17

[Aaron Kaluszka]

No.

Comment 18

[Christian :Biesinger (don't email me, ping me on IRC)]

-> default owner. I know no acceptable way to implement this.

Comment 19

[Peter Weilbacher]

As bug 18574 was ultimately WONTFIXed I do the same to this one.