kwin/NOTES_4_0

This document is for creating the 4.0 release notes. There are 3 parts:
- the notes themselves
- comments and todo's about what should be added to them
- comments about what should be in the accompanying kwin 4.0 video

4.0 release notes
=================


- Performance/smoothness with nVidia cards: Smoothness of KWin rendering
  can be improved by setting env.variable KWIN_NVIDIA_HACK to 1 (e.g. append
  "export KWIN_NVIDIA_HACK=1" to your ~/.profile file). This sets __GL_YIELD=NOTHING
  for KWin, letting KWin use more CPU time for OpenGL operations, however
  at the expense of affecting performance of other applications. This is
  therefore disabled by default. This setting may be removed in the future
  if the negative impact becomes insignificant. See section "OPENGL YIELD BEHAVIOR"
  in README.txt for nVidia cards.

- XRender mode: It is possible to use XRender for compositing instead of the default OpenGL.
  XRender mode in general has less features, however at the moment it is also considered
  unstable - it has not received as much testing as OpenGL mode, some features may be incomplete
  and it is recommended to use the OpenGL mode if possible. Also note that current XRender
  implementations often perform rather poorly.


Comments
========

- mention how to turn it on
- refer to COMPOSITE_HOWTO?
- mention API is unstable, work in progress and whatnot
- hmm, better mention compositing as a whole is still somewhat experimental :)


Video
=====