Xi Shen posted on Tue, 02 Feb 2010 23:01:24 +0800 as excerpted: > for kde, its own window manager seems not to support dual-screen very > well. the windows are not aware of the boundary of the displayer, and is > stretched to two displayer when maximize. i replaced its own window > manager with compiz, and dual-head works very well. two screens are > independent, and windows can move across each other.
Actually, kwin is quite dual-screen aware, with a number of config options related to that. However, they're probably controlled by the xinerama USE flag (which applies to several kde and other apps, including kde's ksmplash, kwin, libplasmaclock, plasma-workspace, and systemsettings/ kcontrol, non-kde xine-lib and mplayer, as well as qt-gui), and if you didn't have it enabled, they'll not show up in "the application formerly known as kcontrol" (the now badly misnamed system settings, with settings that control not the system, but kde, so the name is not only so generic it's useless, it fails to describe the functionality as well!). With USE=xinerama enabled and multiple monitors also enabled in other than clone mode, in kcontrol, under Computer Administration, Display, Multiple Monitors, there's quite a number of options. There, multiple monitor support can be enabled or disabled individually for virtual desktops, window resistance (snap-to when moving), window placement, window maximize (what you mentioned), and window fullscreen. There's also an option controlling which screen gets new windows, 1, 2(,...), or display- containing the pointer. Then under Look & Feel, Window Behavior, Window Behavior, on the Focus tab, there are the options Separate screen focus and Active screen follows mouse. Thus, with the xinerama USE flag and the right options set in kcontrol, multiple monitor maximize is just the beginning. There's all sorts of kde multi-monitor options and support. That said, while kwin is pretty nicely multi-monitor aware, some of the other support, such as in plasma, works but is somewhat buggy. It works in that each monitor gets its own "activity" (so with two monitors, there's two separate activities shown), but it's buggy in that switching resolutions, in particular, switching between clone mode and separate displays, doesn't always work as well as it should. Additionally, kde's own resize and rotate (randr) extension tool is *SERIOUSLY* bugged thru 4.3 at least. 4.4 is said to have some of the issues fixed, we'll see. But with 4.3, on a lot of hardware/x-drivers, while it can see multiple monitors, the only thing it can do with them is run them in clone mode. Depending on the specific version, just entering the Size & Orientation kcontrol applet is enough to screw things up, you don't even get a chance to hit apply or cancel, it initiates clone mode just by entering that applet! This is definitely the case on both the old Radeon 9200 I had (1 DVI and one analog db-15 output, DVI-0 and VGA-0 in xrandr) and the new Radeon hd4650 I'm running now (two DVI outputs, DVI-0 and DVI-1), as well as the Intel graphics on my Acer Aspire One netbook (built-in LVDS-0 and external VGA-0). Thankfully the command-line xrandr works, and I have a script I've setup that handles my main machine (with the Radeon) using it, but it's not (yet) generalized enough to handle the AA1, which I've only started experimenting with in terms of multi-monitor. Thus I know that multi- monitor works on it, but not with the kde display size and orientation applet, and I've only played around with xrandr enough to know it works, I've not setup the easily invoked scripts to handle it yet that I have on the main machine. But kde 4.4 is supposed to have improved substantially in this area. Maybe I won't need to bother with the script, if kde's applet works on it. We'll see. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman
