The shadow effect is known to be broken since at least 4.5.
It is unfortunately in a state which makes it difficult to maintain
and the architecture has some serious drawbacks. Therefore it is the
best solution to replace the effect with a new and better
implementation. For more information about the new implementation
please see the discussion on KWin mailinglist:
http://lists.kde.org/?l=kwin&m=129607406517609&w=2
This also "fixes" all existing bug reports about the shadow effect.
Most of the bugs will really be fixed when the new shadow system is
implemented, if not it is a new bug and a new report should be created
for it.
Please excuse that we go this unnormal approach to mark bugs as
fixed with code removal.
BUG: 164084
BUG: 160948
BUG: 189241
BUG: 229164
BUG: 258663
BUG: 216709
BUG: 243890
FIXED-IN: 4.7.0
Our primary target is Texture From Pixmap and it is supported
by all important drivers nowadays. If a driver is not able to
support TFP using OpenGL at all is probably no good idea and
XRender is more suited.
We have ksnapshot for that which uses a KWin effect to get
screenshots including shadows, which was not possible with
KWin's own implementation.
This invalidates bugs about this functionality.
BUG: 263409
FIXED-IN: 4.7.0
The usefulness of the snow effect is doubtable and it is rather
difficult to port the effect to the new rendering architecture
introduced with GLES. It is probably easier to rewrite the complete
effect from scratch, therefore it is removed for now.
I might consider readding it for 4.7.
This kind of "fixes" snow related bug reports.
BUG: 259362
BUG: 254498
FIXED-IN: 4.7.0
The class is not used by any effect any more and the
design of the ShaderEffect makes it hardly usable.
For most effects just rendering the windows with the Shader
attached to it makes more sense than rendering the complete
screen into a FBO and apply the shader on the off-screen texture.
The effect has been known to cause some problems for quite some time
and is not really useful. Therfore dropping the effect.
See discussion on kwin mailinglist:
http://lists.kde.org/?l=kwin&m=129597766829618&w=2
It now uses a GLShader for GLSL shaders and pushes it using the
ShaderManager.
It does not work with the nouveau driver plus GLES, but it works
with fglrx + desktop GL 2.x, so I assume it is a driver problem here.
It uses a generic vertex shader and because of that it needs to
mark all windows which are inverted as transformed.
There is currently a conflict with Lanczos (or thumbnails) and with
the desktop in cube effect.
When rendering opaque (RGB-only) windows the alpha ends up to be 0
with blending disabled. This breaks subsequent rendering steps which
require blenden (e.g. Lanczos). Therefore a uniform is used to ensure
that the alpha channel is set to 1.
Rotation is now only handled by the QMatrix4x4 m_rotationMatrix,
so no more need for display lists. Resulting in a cleaner code without
differences between OpenGL 1.x and 2.x/GLES.
