The multi-monitor situation
===========================
Michael Stapelberg <michael@i3wm.org>
-July 2012
+April 2013
-…or: oh no, I have an nVidia graphics card!
+Please upgrade your nVidia driver to version 302.17 or newer and i3 will just
+work. This document is kept around for historic reasons only.
== The quick fix
If you are using the nVidia binary graphics driver (also known as 'blob')
-you need to upgrade to at least version 302.17 (released in June 2012).
-
-In case you cannot update the driver to 302.17 or newer on your machine for
-some reason, use the +--force-xinerama+ flag (in your .xsession) when starting
-i3, like so:
+before version 302.17, you need to use the +--force-xinerama+ flag (in your
+.xsession) when starting i3, like so:
.Example:
----------------------------------------------
== The explanation
-Starting with version 3.ε (March 2010), i3 uses the RandR (Rotate and Resize)
-API instead of Xinerama. The reason for this, is that RandR provides more
-information about your outputs and connected screens than Xinerama does. To be
-specific, the code which handled on-the-fly screen reconfiguration (meaning
-without restarting the X server) was a very messy heuristic and most of the
-time did not work correctly -- that is just not possible with the little
-information Xinerama offers (just a list of screen resolutions, no identifiers
-for the screens or any additional information). Xinerama simply was not
-designed for dynamic configuration.
+Starting with version 3.ε, i3 uses the RandR (Rotate and Resize) API instead
+of Xinerama. The reason for this, is that RandR provides more information
+about your outputs and connected screens than Xinerama does. To be specific,
+the code which handled on-the-fly screen reconfiguration (meaning without
+restarting the X server) was a very messy heuristic and most of the time did
+not work correctly -- that is just not possible with the little information
+Xinerama offers (just a list of screen resolutions, no identifiers for the
+screens or any additional information). Xinerama simply was not designed
+for dynamic configuration.
So RandR came along, as a more powerful alternative (RandR 1.2 to be specific).
It offers all of Xinerama’s possibilities and lots more. Using the RandR API
As RandR has been around for about three years as of this writing, it seemed
like a very good idea to us, and it still is a very good one. What we did not
-expect, however, was the nVidia binary driver. It did not support RandR until
-mid 2012, even though nVidia had announced that it will support RandR
-previously. What does missing RandR support mean for you? First of all, you are
-stuck with TwinView and cannot use +xrandr+. While this ruins the user
-experience, the more grave problem is that the nVidia driver not only does not
-support dynamic configuration using RandR, it also does not expose correct
-multi-monitor information via the RandR API. So, in some setups, i3 will not
-find any screens; in others, it will find one large screen which actually
-contains both of your physical screens (but it will not know that these are two
-screens).
+expect, however, was the nVidia binary driver. It still does not support RandR
+(as of March 2010), even though nVidia has announced that it will support RandR
+eventually. What does this mean for you, if you are stuck with the binary
+driver for some reason (say the free drivers don’t work with your card)? First
+of all, you are stuck with TwinView and cannot use +xrandr+. While this ruins
+the user experience, the more grave problem is that the nVidia driver not only
+does not support dynamic configuration using RandR, it also does not expose
+correct multi-monitor information via the RandR API. So, in some setups, i3
+will not find any screens; in others, it will find one large screen which
+actually contains both of your physical screens (but it will not know that
+these are two screens).
For this very reason, we decided to implement the following workaround: As
long as the nVidia driver does not support RandR, an option called
projects / i3 / i3.github.io / blobdiff