4 Replies Latest reply on Jul 13, 2012 1:04 PM by Mosga

    "Stretch Guest" gives distortion at full screen

    Mosga Lurker



      Latest TP2012, just like some previous versions (I evaluated VMWare Workstation 8 and it had same bug) has distortion for "Full screen" mode under Linux host, when "Stretch guest" is activated.


      My system is: Fedora 17 x86-64 (same bug existed on VMware 8 on Fedora 16), ATI Radeon 4870 running opensource xorg-x11-drv-ati-6.14.4 driver under Gnome 3 (3.4 in F17, 3.2 in F16).

      When guest display's resolution is lower than host's (doesn't matter if it's just Windows desktop or some game that locks screen resolution on 640x480) and VMWare is running in "full screen" mode, after activating "Stretch guest" option image is stretched to the whole screen, however there are some small random distortions, like on fonts some horizontal or vertical lines can be doubled, or line of pixels is missing from desktop icons, stuff like that. These distortions mostly follow mouse - moving mouse cursor around makes distortions happen in some rectangle that surrounds mouse cursor. The mouse isn't only source of distortion, as some image changes can cause them too. This makes text hard to read and some graphics pretty ugly.

      It doesn't depend on host resolution (changing it with xrand doesn't do anything), but visibility of these distortions increases as guest resolution drops (i.e. stretch ratio increases); for example, they are hardly noticeable in 1280x960 guest resolution (host is running 2560x1600 here), but very noticeable for 800x600 and 640x480 guest resolution. Guest is running Windows XP here, but I'm pretty sure it also happens with older Windows versions.


      If the description is bad, I can try to capture video of it (it would be much more noticeable than on still image), however I don't know a good mean of doing it; if someone kindly will suggest me some linux software that can take screencast of fullscreen application like VMWare, I can try to make a video.


      I tried lowering graphics acceleration level in guest and some other tricks but was never able to solve this problem.


      Similar problem doesn't exist in TP2012 running on Windows host.


      Also, as a side note, whenever fullscreen 3D game is running, this distortion disappears - it can run in lower resolution stretched to fullscreen and there are no distortions at all. Additionally, after exiting it for a few seconds there are no distortions on desktop - it renders perfectly and there are no distortions following mouse. It looks like VMWare changes rendering mode for 3D or something like that. Additionally, the rendering feels a bit "laggy" during this time. However, as few seconds pass, the screen flickers slightly and distortions returns.


      I wonder if anyone else experiences this problem on Linux and if there is a way to solve it?

        • 1. Re: "Stretch Guest" gives distortion at full screen
          raiford Enthusiast

          I don't normally run in full screen or with stretched mode, but I just tested this and can confirm the same behavior.  As you described, the distortion follows the mouse - everywhere else looks good.  My distortion is a little different than you described though.. rather than having lines double up, I'm seeing the lines shift.  Its almost like a really slight magnifying effect.  I'm guessing VMWare tracks the mouse and repaints the screen around it.  The distortion appears like a calculation is slightly off for this repainting.. almost like it thinks the screen size is slightly taller or shorter.


          I'm running Fedora 17 (Gnome3) with the nouveau driver (nVidia).

          • 2. Re: "Stretch Guest" gives distortion at full screen
            mfelker Expert

            I am not seeing  distortion  as you describe but it might very be there for me the poblem is lower resolution.  The desktop (doesn't matter what OS) is far less clear and fuzzy as well.  i probably can correct this in the guest itself (at least Windows) but I ususally only use this mode when I wish to avoid scroll bars or more easily close Windows porgrams on the guest.  Although the resolution in full screen is normal I can't  seem to avoid a black border around the OS image - its not much of an advantage unless you like the menu on the top of the screen.  I would use stech more often if the resolution  were better.  It would doubless look even worse in games.

            • 3. Re: "Stretch Guest" gives distortion at full screen
              Mosga Lurker

              mfelker: I think this is expected, with the scaler mode used in VMWare you will always get blurry picture. There is no helping it - there are other ways of upscaling, but it's impossible to add details that aren't there, so when upscaling from low resolution image will always be either blurry or pixelated, it's the matter of preference.

              However, scale mode is somewhat valuable to me, as running 640x480 on 2560x1600 screen without upscaling gives horrible experience. I don't mind blurriness or pixelated look or whatever, but distortion *is* a big problem for me. Maybe it's not present in your system. What is your host OS and video card/driver?..


              raiford: yes, I think we are talking about same thing. Doubling likes come from that magnifying glass-like distortion. Unfortunately, mouse isn't the only source of distortion on screen: when text or graphics changes/scrolls/moves it can occur even in places outside of mouse cursor area.


              Technically, I don't even need "full screen" scaling, just upscaling guest 2x or 3x times or something would be fine for me, but full screen + stretch guest seems to be the only option that VMWare offers, and I wish it would work correctly at least..

              • 4. Re: "Stretch Guest" gives distortion at full screen
                Mosga Lurker

                This is still an issue with June Tech Preview..