This file lists TODO items for the compositing code. See file COMPOSITE_HOWTO for setting up kwin_composite. See file HACKING for details on developing KWin, including building the kwin_composite branch. See effects/howto.* for a HOWTO on writting effects. See documentation in source (mainly in scene.cpp) for description of the design of the compositing framework. TODO ================================= * = not done, will be either done by me, or should be at least discussed first with me + = not done, I don't plan on doing it that soon - in other words, these should be the best ones for you if you want to help ! = like +, but they should be relatively simple - in other words, these should be the best if you want to get started with the code / = work in progress ? = should it be done? % = should be probably done later, during cleanups and preparations for being stable General TODO ================================= ? alpha clear hack + - find out if it affects performance + - if yes, try to find a better way of solving the problem ! - since kompmgr has an option to make only the decoration transparent, it should be possible to do the same here - if the window has alpha and a decoration or if there should be only the decoration transparent, paint first the contents and then the decoration - this should make it possible to paint the decoration without the random alpha that is right now handled by the alpha hack * don't add workspace damage in Toplevel::addDamage() - instead add damage of windows to the screen only before doing the painting - this should prevent repaints because of changing obscured windows * - also, provide a call to just mark a window as needing repaint but not being damaged - this will prevent rebinding the pixmap or updating the texture - http://lists.kde.org/?l=kwin&m=116836151626848&w=2 * wait for decoration repaints - it is sometimes visible that the window contents are painted first and the decoration only afterwards with a small delay - maybe posted paint events need to be processed immediatelly, or maybe the compositing code should not update the window until the decoration is finished painting ! compile even without OpenGL or XRender - kwin_composite currently requires both OpenGL and XRender to build - compiling without either results in compile errors, needs to be fixed ! - scene_xrender.cpp also requires XFixes ! - check whether it compiles fine without XComposite/XDamage ? Expose events for overlay window - is it necessary to track it, like with root window? % paint throttling - there's 5ms grace period per repaint to avoid overloading the system with just compositing and not letting the system do anything else - check and evaluate + support for new window types from the wm spec for compositing - this will have to be done in Qt, kdecore and kwin * handle properly stacking order of deleted windows for showing in effects * handle properly deleted windows that reappear (windowReadded() function?) / consider using an extra class for representing deleted windows - cleaning up Client/Unmanaged instances may still leave e.g. timers around if they're overlooked - an extra class could copy some interesting data and "replace" the old instance + Deleted::windowType() does not work % during screensaving, do no let non-screensaver windows show above screensaver - kdesktop_lock watches for such things and raises again, but there's a small gap % nvidia drivers by default use fake refresh rates as a workaround for some X limitations - see the DynamicTwinView section in nvidia README - this makes KWin repaint at a different rate than it should OpenGL TODO ================================= / Check/make it work with other gfx cards ? Xgl support - Compiz itself doesn't work when compiled with the libGL from nvidia, it ships its own and links against it ? - might be worth trying to use that libGL as well - it may be just because of the special libGL, but when testing with Xgl it even seemed non-conformant - none of the provided configs had GLX_RENDER_TYPE with GLX_RGBA_BIT even though required by GLX and other funny things. Indeed, it may be just me being still pretty clueless about these things. ? - is there a good reason to support Xgl? With the 9625 nvidia drivers it seems to work fine without them and there's AIGLX + AIGLX support - kind of works, needs more work + - it needs indirect rendering, should be autodetected and disabled somehow % - may require LIBGL_ALWAYS_INDIRECT set with older X.org (http://lists.kde.org/?l=kwin&m=116439615124838&w=2) (http://lists.freedesktop.org/archives/xorg/2006-December/020323.html) / GL_ARB_texture_rectangle vs GL_ARB_texture_non_power_of_two % - works; bugs in tfp_mode with power_of_two textures - ati (others?): power_of_two windows are drawn white unless non-tfp_mode is forced in findTextureTarget() ? in SceneOpenGL::bindTexture() with tfp_mode, with some gfx cards it seems to be faster to not short-circuit the texture binding when there's been no damage + strict binding - there is code to support strict binding as required by AIGLX, but it's disabled, because copy_buffer in bindTexture() ensures strict binding as a side-effect - since copy_buffer hack should be removed in the future, strict binding will need to be enabled then - http://lists.kde.org/?l=kwin&m=116363084129170&w=2 % bindTexture() optimize copied areas - right now bindTexture() updates every damaged area and resets the window damage - it might make things faster to update only areas that need to be repainted and keep the rest damaged until needed % clipping optimization - like XRender code has paintTransformedScreen(), avoid painting parts that are obscured (makes a difference with many windows open) - http://lists.kde.org/?l=kwin&m=116585618111882&w=2 + shm mode needs support for more data formats than GL_BGRA in order to support e.g. 16bpp mode - http://www.xfree86.org/current/glTexImage2D.3.html % with current nvidia glXCreatePixmap in tfp mode fails with pixmaps 32x32 and smaller XRender TODO ============================== + SceneXrender::Window::performPaint() doesn't use saturation + SceneXrender::Window::performPaint() doesn't use brightness Effects framework TODO ============================== * more notification functions for effects are needed - currently there are only very few notification functions (windowAdded, windowActivated,...) ! - window state changes ? more * shadows / support for grabbing input - during some more complicated effects, input (at least mouse) should be disabled, because currently there is no way to do input redirection * pre-paint pass should be done completely before the paint pass - currently prePaintWindow() is done only after paintScreen() has already started, which means that if an effect sets PAINT_WINDOW_TRANSFORMED it needs to set it also in prePaintScreen() * PAINT_WINDOW_DISABLED turning off from effects needs some utility functions - a window may have painting disabled for various reasons and their numbers may increase over time - so e.g. an effect showing minimized windows cannot simply turn off DISABLED for minimized windows, because it may be disabled also for other reasons - there should be some utility function that will be called by the effect with arguments saying which disabled windows it wants enabled + EffectWindow should be completely opaque when kept as the only API for effects - no inlines, etc. Effects TODO =============================== + adapt the kcontrol module used by Kompmgr - in kcmkwin/kwinoptions ! - uses ~/.xcompmgr, convert to use normal KConfig ? - I don't think these effects should be plugins or anything like that, probably simply write to kwinrc and use the Option class in KWin + implements all effects Kompmgr could do + - all effects from the Opacity tab should be already doable ! - applying translucency only to the decoration - use clientSize() and clientPos() from Client - see also the alpha clear hack todo entry ! - not usign ARGB visuals - just clear the alpha channel in the alpha clear hack - or do it while painting (see also the alpha clear hack todo entry) ! - the rest - should be simple * - shadows - framework is not ready for them yet (see the todo entry) + - tab Effects ! - fade-in should be simple + - fade between changes - will need notification about opacity changes - not sure if this is doable for other opacity changes then the ones initiated by the user or by the application * - fade-out needs framework for disappearing windows (see the todo entry) + minimize/shade effects - to replace the ones from KWin core - Client::animateMinimizeOrUnminimize() - Client::setShade() / zoom effect - enlarge a portion of the screen + logout effect * - should be triggered by ksmserver somehow + effects to replace widget effects (the ones in the Effects tab in "kcmshell style") + - needs support for new window types from the current draft of the EWMH WM spec + - needs patching Qt, netwm* classes in kdecore / showfps effect - for debugging, just shows transparent fps in some corner - just painting the number in paintScreen() should do, with glPushMatrix() and glLoadIdentity() to avoid all transformations + - needs bindPixmapToTexture() or something like that, for displaying the text - should also detect kwin being idle - it probably should detect in pre-paint that the only damage is its own area and avoid damaging for the next round in post-paint + debugpaint effect - should show what is damaged during each repaint step - probably just e.g. paint a red almost transparent area over damaged areas - needs special care to avoid causing infinite loops by its own damage (i.e. it damages part of screen to clear its own painting, that triggers itself again next repaint) ? other effects + merge fadein and fadeout effects - so that they don't conflict and share the progress + virtual desktop change effects + - ... yes, you guessed it, the cube + - something that presents all virtual desktops as being in grid (as in pager) and zooms out of the old one and into the new one - or whatever