bugGNUstep - Bugs: bug #26535, user created NSImage not...


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bug #26535: user created NSImage not displaying properly

Submitted by:  Scott Christley <schristley>
Submitted on:  Mon 11 May 2009 10:28:28 PM UTC  
Category: Gui/AppKitSeverity: 3 - Normal
Item Group: BugStatus: Confirmed
Privacy: PublicAssigned to: Fred Kiefer <FredKiefer>
Open/Closed: Open

Sat 01 May 2010 04:46:49 PM UTC, comment #2:

Just a short update on this bug. The problem still persists and in the meantime I also looked into the second issue. At the moment GNUstep isn't able to do any drawing in a secondary thread. The code fails when it tries to cache the image rep and cannot find a display server for the current thread.

Fred Kiefer <FredKiefer>
Project MemberIn charge of this item.
Wed 27 May 2009 07:19:44 PM UTC, comment #1:

Hi Scott,

this is just to let you know that I started to investigate these problems. Sorry for taking so long, but I first was away and then had a lot of other stuff that needed to be taken care of. On the other hand I really seem to be the only one to address such issues in GNUstep. We need to change that.

Your bit size is a nice typo, it left me guessing whether you have 32 or 64, but in reality this isn't that important here.

Thank you for your excellent test application, this clearly shows the problems. As you pointed out we have two issues, one with scaling and one with background threads. Up to now I only looked into the first one.

The code at fault is the one in [NSImage drawInRect:fromRect:operation:fraction:]. In the scaled case we end up using the NSBitmapImageRep to draw and not the interally created NSCachedImageRep (line 1157). And at this point the bitmap is empty, so it doesn't really help. On the other hand, cached images can only draw scaled via a horrible hack (See NSCachedImageRep draw]. It would be possible to resolve this for the cairo backend by moving the actual drawing into the backend, but I still need a solution for the other backends.

Fred Kiefer <FredKiefer>
Project MemberIn charge of this item.
Mon 11 May 2009 10:28:28 PM UTC, original submission:
  • Scaling of user created images not working.
  • Drawing in images in secondary threads not working.

I'm using GNUstep from SVN on Debian 34-bit intel.

Scott Christley <schristley>


Attached Files
file #18126:  ImageTest.tgz added by schristley (47KiB - application/x-gzip - Test application showing image problems)


Depends on the following items: None found

Items that depend on this one: None found


Carbon-Copy List
  • -unavailable- added by FredKiefer (Posted a comment)
  • -unavailable- added by schristley (Submitted the item)

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    Follow 3 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Wed 27 May 2009 07:19:44 PM UTCFredKieferStatusNone=>Confirmed
      Assigned toNone=>FredKiefer
    Mon 11 May 2009 10:28:29 PM UTCschristleyAttached File-=>Added ImageTest.tgz, #18126

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