Closed Bug 123511 Opened 19 years ago Closed 19 years ago
PNG containing alpha channel (transparency) as background image has redraw problems
290 bytes, image/png
A background image with transparency is not properly redrawn if a program window moves over it left-right or the browser window moves outside the screen left-right. If the movement (program or browser window) is up/down everything is drawn correctly. If you move left/right the backgound is drawn in the color of the left most pixel of the image. This problem does only occur if the picture has a transparency layer. To test this behaviour you can use the above mentioned URL and move a window over the upper left picture. To simplify the testing you can use following small html code: <html> <body> <table> <tr> <td background="back.png"> TestTestTestTest </td> </tr> </table> </body> </html> The image must have a transparency layer. Create for instance a small horizontal bar with green color to the left and red color to the right. I can also provide you a sample picture by email. This is a new bug with 0.9.8 (I haven't had this with 0.9.7). Timo
I've added a sample picture to be used with the given html code to reproduce the bug. Timo
look like a dupe of bug 121230 : png (containing alpha channel) as background causes display errors
It seems to be related. I verified that it only happens with png images containing an alpha channel (added png in summary). Furthermore I have to correct my first posting: it also happens if one moves a window up/down over the background image. In this case the image is repainted with the colors taken from the upper line of the image. I will add a modified background image to show the up/down behaviour.
Summary: Transparent background image redraw problem → Transparent png background image redraw problem
The URL http://dbs.uni-leipzig.de will not work as a test case anymore since the alpha channel was removed from the images. Please use the given html code and the attached image to reproduce the bug.
*** This bug has been marked as a duplicate of 121230 ***
Status: UNCONFIRMED → RESOLVED
Closed: 19 years ago
Resolution: --- → DUPLICATE
Reopening migrating keywords see bug 121230
Status: UNCONFIRMED → NEW
Ever confirmed: true
Summary: Transparent png background image redraw problem → PNG containing alpha channel (transparency) as background image has redraw problems
*** Bug 125484 has been marked as a duplicate of this bug. ***
*** Bug 138430 has been marked as a duplicate of this bug. ***
Reduced testcase: http://bugzilla.mozilla.org/attachment.cgi?id=79962&action=view
http://home.t-online.de/home/09135725943-0001/cp/index.html sample url - watch the "windows" to the right. they should have a slightly translucent background which gets lost when moving the window out of the screen, ... additional try to click twice on the caption of those windows, which minimizes and enlarges them again. there are some problems too... bug 125896 seems to be related
I started seeing this too. I believe this is caused by some of dcone's changes to the way we draw images on windows.
Assignee: pavlov → dcone
This is a duplicate of 137223.. which I posted a patch for. *** This bug has been marked as a duplicate of 137223 ***
Status: NEW → RESOLVED
Closed: 19 years ago → 19 years ago
Resolution: --- → DUPLICATE
Status: RESOLVED → VERIFIED
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