Bug 142321

Summary:	MNG file misdrawn (old frames still visible behind current frame)
Product:	[Unmaintained] kview	Reporter:	esigra
Component:	kviewviewer	Assignee:	Unassigned bugs mailing-list <unassigned-bugs>
Status:	RESOLVED UNMAINTAINED
Severity:	normal	CC:	finex
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	Gentoo Packages
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Test application for reproducing the bug. Test application for reproducing the bug with Qt4

Description esigra 2007-02-28 12:08:29 UTC

Version:            (using KDE KDE 3.5.5)
Installed from:    Gentoo Packages
OS:                Linux

Open the URL [http://cryptology.org/research/SDL MNG Library/SDL_mng-0.1.tar.bz2] in Konqueror. (It will embed the archive viewer.) Right-click on panda.mng and select Show in the context menu. A window opens where the dancing panda animation is drawn. But it seems like the old frames are still visible behind the current frames, so the panda leaves a trail. The same drawing error is seen if the file is opened directly in Konqueror (it seems to embed the same viewer part). showimg has the same problem as the other KDE viewers. The test program in the package containing the animation shows the animation correctly.

Comment 1 esigra 2007-03-16 16:09:47 UTC

Created attachment 19997 [details]
Test application for reproducing the bug.

Further investigation has shown that this bug is reproducible without KDE (only
Qt). Here is a small Qt test program:
#include <qapplication.h>
#include <qlabel.h>
#include <qmovie.h>

int main(int argc, char * * argv) {
	QApplication a(argc, argv);
	QLabel & label = *new QLabel(0);
	label.resize(96, 96);
	label.setMovie(QMovie("panda.mng"));
	label.show();
	a.connect(&a, SIGNAL(lastWindowClosed()), &a, SLOT(quit()));
	return a.exec();
}

To reproduce
1. Unpack the attached file.
2. Change to the directory qt3mngtest that was created when the file was
unpacked.
3. Copy the file panda.mng (from the location in the original bug report) into
this directory.
4. Make sure that the qmake in your path is from Qt3.
5. Execute "kdevelop qt3mngtest.kdevelop&".
6. Press F8. The test program is being built.
7. Change back to Konsole and execute bin/qt3mngtest. The application now shows
the dancing panda, but with this bug.

Comment 2 esigra 2007-03-16 16:39:41 UTC

Created attachment 19998 [details]
Test application for reproducing the bug with Qt4

I made a corresponding testcase for Qt4. Unfortunately the bug is there too. I
notice that with Qt3 the background was cleared when the animation was
restarted, but with Qt4 it seems to never be cleared. Here is the body of the
test program:
#include <qapplication.h>
#include <qlabel.h>
#include <qmovie.h>

int main(int argc, char * * argv) {
	QApplication a(argc, argv);
	QMovie movie("panda.mng");
	QLabel label;
	label.resize(96, 96);
	label.setMovie(&movie);
	label.show();
	movie.start();
	a.connect(&a, SIGNAL(lastWindowClosed()), &a, SLOT(quit()));
	return a.exec();
}
To reproduce:
 1. Unpack the attached file. 
 2. Change to the directory qt4mngtest that was created when the file was 
 unpacked. 
 3. Copy the file panda.mng (from the location in the original bug report) into

 this directory. 
 4. Make sure that the qmake in your path is from Qt4. 
 5. Execute "kdevelop qt4mngtest.kdevelop&". 
 6. Press F8. The test program is being built. 
 7. Change back to Konsole and execute bin/qt4mngtest. The application now
shows the dancing panda, but with this bug.

Comment 3 esigra 2007-03-23 08:58:19 UTC

Qt bug tracker: [http://www.trolltech.com/developer/task-tracker/index_html?method=entry&id=155269]

Comment 4 esigra 2008-02-07 14:09:36 UTC

I tried again with the Gentoo package x11-libs/qt-gui-4.4.0_rc1 and it seems like the situation has improved! The animation does not leave a trail. However there seems to be one remaining problem. The animation flickers shortly after the first iteration (Seems like one frame becomes completely blank). Then it loops forever without problem.

Comment 5 FiNeX 2008-12-26 23:32:37 UTC

Kview is no more mantained/developed. This bug wish will not be fixed until a new developer will work on it. Moreover this product is not ported to KDE4. On KDE4 it has been replaced by another software. I'm closing this bug as "unmantained". I'm sorry.

Regards.