According to the OpenGL ABI for Linux GLX 1.3 is a minimum requirement.
Therefore we do not need to resolve the symbols which are present in that
version.
KWin did always require at least 1.3, for all the resolved functions
there were checks in the Scene, but they might have been incorrect.
Instead now the GLX version is checked and OpenGL compositing is blocked
if there is not at least GLX 1.3.
REVIEW: 106704
glBlendColor has been added to OpenGL 1.2 which means it is part of
the OpenGL ABI defined for Linux.
See http://www.opengl.org/registry/ABI/ section 3.4.
The macro GL_RESOLVE_WITH_EXT was fundamentally broken as it tried to
resolve a symbol first by it's name and then by the extension name if
the returned pointer is null.
From GLX spec:
"A non-NULL return value for glXGetProcAddress does not guarantee that an
extension function is actually supported at runtime. The client must also query
glGetString(GL EXTENSIONS) or glXQueryExtensionsString to determine if an
extension is supported by a particular context."
This macro is now reworked to be used only in case the symbol name does
not match our function name. E.g. glUniform1f vs glUniform1fARB.
The resolving itself also had quite some issues as:
* in same cases function pointers are not nulled
* in same cases only the arb or only the ext is checked
* in same cases the wrong extension is checked
This is now reworked to always check first the ARB extension if available
then the EXT extension and if both are not available the pointers are set
to NULL.
The Egl backend is decoupled from the OpenGL ES build option which makes
it possible to use it as a replacement for glx.
To make this possible a new build flag is added when egl is available at
compile time and any egl specific code is now ifdefed with this flag
instead of the gles flag. In addition at runtime a windowing system enum
value is passed to the various detect methods to have egl/glx specific
detection for e.g. function pointer resolving.
By default egl is used if compiled with OpenGL ES, otherwise glx is used.
But in the non-gles case the windowing system can be selected through the
new environment variable KWIN_OPENGL_INTERFACE. Setting this variable to
"egl" the EglOnXBackend is used.
REVIEW: 106632
This build option is added to make it easier to build just KWin without
kde-workspace. This is a common requirement by developers wanting to
contribute to KWin and only want to build KWin but use everything else
from their normal distribution.
Building KWin standalone is very often difficult due to Oxygen. If the
library has changed it is not possible to build just KWin without also
building the workspace libs and if you do so you run into ABI problems
when trying to start KWin - either the decoration or the style is
crashing due to not matching libraries.
To circumvent this common issue for new developers this build option
is introduced to just exclude the Oxygen window decoration and defaulting
to Plastik.
Of course by default this option is turned ON, so that the Oxygen
decoration gets build. By default there is no change at all.
REVIEW: 106303
The ShaderBinder class can be used for the case that a block of code
should be executed with a given Shader being bound. This is useful for
all the cases where there is a if-block for OpenGL2 execution with a
Shader being pushed in the first line to the ShaderManager and popped in
the last line of the block. With the helper this can be simplified to:
ShaderBinder binder(myCustomShader);
or
ShaderBinder binder(ShaderManager::GenericShader);
The ctor of ShaderBinder pushes the given Shader to the stack and once
the helper goes out of scope it will be popped again from the stack.
In addition the helper can take care of OpenGL 1 compositing, that is it
just does nothing. So it can also be used where there is a shared OpenGL1
and OpenGL2 code path where the Shader should only be pushed in OpenGL2.
This basically removes all the checks for the compositing type before
pushing/popping a Shader to the stack.
REVIEW: 106521
The main usage of ShaderManager::isValid was to have OpenGL2 specific
code pathes. Now we have an actual OpenGL2Compositing type and we know
that the ShaderManager is valid if we have this compositing type and we
know that it is not valid on OpenGL1Compositing. This gives us a much
better check and allows us to use the isValid method just for where we
want to check whether the shaders compiled successfully.
In addition some effects require OpenGL2, so we do not need to check
again that the ShaderManager is valid. Such usages are removed.
The CompositingType enum turns into flags and two new values are
introduced: OpenGL1Compositing and OpenGL2Compositing.
Those new values are or-ed to OpenGLCompositing so that a simple check
for the flag OpenGLCompositing works in case of one of those two new
values. To make the generic check for OpenGL compositing easier a method
in EffectsHandler is introduced to just check for this.
The scenes now return either OpenGL1Compositing or OpenGL2Compositing
depending on which Scene implementation. None returns OpenGLCompositing.
In the maximized state the enabled borders were still enabled causing
the actual borders to be still shown. In addition the padding is not
adjusted to be 0. This is done in the C++ part is it does not make any
sense to have shadows being thrown to another screen for a maximized
window.
REVIEW: 106576
BUG: 307365
FIXED-IN: 4.9.2
Replace dynamic_casts to check the type for for Toplevel by isFoo()
calls and use static_casts in such blocks.
Furthermore method shape() returns now a constant reference instead of a
copy of the QRegion.
REVIEW: 106364
SceneOpenGL turns into an abstract class with two concrete subclasses:
* SceneOpenGL1
* SceneOpenGL2
It provides a factory method which first creates either the GLX or EGL
backend which is passed to a static supported() method in the concrete
sub classes. These method can test whether the backend is sufficient to
be used for the OpenGL version in question. E.g. the OpenGL 2 scene
checks whether the context is direct.
The actual rendering is moved into the subclasses with specific OpenGL 1
and OpenGL 2 code. This should make the code more readable and requires
less checks whether a Shader is bound. This is now known through the
Scene: the OpenGL1 scene will never have a shader bound, the OpenGL2 scene
will always have a shader bound.
To make this more reliable the ShaderManager is extended by a disable
method used by SceneOpenGL1 to ensure that the ShaderManager will never
be used. This also obsoletes the need to read the KWin configuration
whether legacy GL is enabled. The check is moved into the supported
method of the OpenGL2 scene.
REVIEW: 106357
The code was basically copy'n'pasted to handle both Client and Deleted
requiring to cast the Toplevel to both Client and Deleted to test whether
it is one of those.
This is now changed from runtime to compile time polymorphism. A
templated method is used to start the rendering process for the decos.
This on the one hand simplifies the code and on the other does not
require any dynamic casts any more as we use the available check on
Toplevel whether it is a Client or Deleted.
The Window implementation performed many checks whether the rendering
uses the OpenGL 1 or OpenGL 2 code path and there were quite a few
cludges around to make this work.
So instead of many if-else blocks the specific code has now been moved
into a specific sub class and calls to pure virtual method in the base
class are used to trigger this behavior. Although that adds some overhead
in a rather hot code path it should be better than the many chained
method calls used before to handle OpenGL 1 and 2.
It also makes the code a little bit more readable as all the complete
OpenGL 1 implementation is now in one block ifdefed for OpenGL ES.
The handling for creating and managing the OpenGL context is
split out of the SceneOpenGL into the abstract OpenGLBackend
and it's two subclasses GlxBackend and EglOnXBackend.
The backends take care of creating the OpenGL context on the
windowing system, e.g. on glx an OpenGL context on the overlay
window is created and in the egl case an EGL context is created.
This means that the SceneOpenGL itself does not have to care
about the specific underlying infrastructure.
Furthermore the backend provides the Textures for the specific
texture from pixmap operations. For that in each of the backend
files an additional subclass of the TexturePrivate is defined.
These subclasses hold the EglImage and GLXPixmap respectively.
The backend is able to create such a private texture and for
that the ctor of the Texture is changed to take the backend as
a parameter and the Scene provides a factory method for
creating Textures. To make this work inside Window the Textures
are now hold as pointers which seems a better choice anyway as
to the member functions pointers are passed.
