Detect screen refresh rate for finding out optimal compositing

redraw speed. Patch by Philip Falkner.


svn path=/branches/work/kwin_composite/; revision=607253

CMakeLists.txt

@@ -71,6 +71,9 @@ target_link_libraries(kdeinit_kwin  ${KDE4_KDEUI_LIBS} kdecorations ${X11_LIBRAR
 target_link_libraries(kdeinit_kwin -lGL)
 # -ldl used by OpenGL code
 target_link_libraries(kdeinit_kwin -ldl)
+if (X11_Xrandr_FOUND)
+  target_link_libraries(kdeinit_kwin ${X11_Xrandr_LIB})
+endif (X11_Xrandr_FOUND)
 if (X11_Xcomposite_FOUND)
   target_link_libraries(kdeinit_kwin ${X11_Xcomposite_LIB})
 endif (X11_Xcomposite_FOUND)

COMPOSITE_TODO

@@ -16,6 +16,7 @@ TODO
     - 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
@@ -40,7 +41,7 @@ General TODO
     - 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
 
-* handle XRandr changes
+/ handle XRandr changes
     - output buffers and similar probably need recreating when the screen size changes
 
 ! compile even without OpenGL or XRender
@@ -51,17 +52,18 @@ General TODO
 
 ? 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 
+
 
 OpenGL TODO
 =================================
 
 + Check/make it work with other gfx cards
     - I've tested only with nvidia with the 9625 beta drivers and 8776 stable drivers so far
+    - ATI - some (especially R200 chips) seem to work
     - I have absolutely no idea about other gfx cards, needs to be tested
-        - ati
-!           - does kwin_composite work there at all?
-!           - does glcompmgr work there at all? (even with the various switches in the source)
-+           - make kwin_composite work there if it doesn't
         - intel
 !           - does kwin_composite work there at all?
 !           - does glcompmgr work there at all? (even with the various switches in the source)
@@ -80,9 +82,8 @@ OpenGL TODO
 ?   - 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
-    - no idea about this at all
-+   - find out if it works
++ AIGLX support
+    - kind of works, needs more work
 
 ! improved GLXFBConfig support
     - it seems a different config for each depth would be needed
@@ -96,10 +97,6 @@ OpenGL TODO
       one for the root window (or for the window used in the XComposite overlay)
       and the best one for every depth of drawables
 
-/ sync to vblank
-    - currently the compositing code is run with 20ms timer, i.e. constant 50fps
-    - the GLX_SGI_video_sync extension should be used
-
 + GL_ARB_texture_rectangle vs GL_ARB_texture_non_power_of_two
     - code currently uses GL_ARB_texture_rectangle (GL_TEXTURE_RECTANGLE_ARB), using
         normal textures when GL_ARB_texture_non_power_of_two is available should(?) be

composite.cpp

@@ -80,7 +80,34 @@ void Workspace::setupCompositing()
           kDebug( 1212 ) << "No compositing" << endl;
           return;
         }
-    compositeTimer.start( 20 );
+    int rate = 0;
+    if( options->refreshRate > 0 )
+        { // use manually configured refresh rate
+        rate = options->refreshRate;
+        }
+#ifdef HAVE_XRANDR
+    else
+        { // autoconfigure refresh rate based on XRandR info
+        if( Extensions::randrAvailable() )
+            {
+            XRRScreenConfiguration *config;
+
+            config = XRRGetScreenInfo( display(), rootWindow() );
+            rate = XRRConfigCurrentRate( config );
+            XRRFreeScreenConfigInfo( config );
+            }
+        }
+#endif
+    // 0Hz or less is invalid, so we fallback to a default rate
+    if( rate <= 0 )
+        rate = 50;
+    // QTimer gives us 1msec (1000Hz) at best, so we ignore anything higher;
+    // however, since compositing is limited to no more than once per 5msec,
+    // 200Hz to 1000Hz are effectively identical
+    else if( rate > 1000 )
+        rate = 1000;
+    kDebug( 1212 ) << "Refresh rate " << rate << "Hz" << endl;
+    compositeTimer.start( 1000 / rate );
     lastCompositePaint.start();
     XCompositeRedirectSubwindows( display(), rootWindow(), CompositeRedirectManual );
     if( dynamic_cast< SceneOpenGL* >( scene ))

options.cpp

@@ -194,6 +194,7 @@ unsigned long Options::updateSettings()
     removeShadowsOnResize = config->readEntry("RemoveShadowsOnResize", QVariant(true)).toBool();
     onlyDecoTranslucent = config->readEntry("OnlyDecoTranslucent", QVariant(false)).toBool();
     
+    refreshRate = config->readEntry( "RefreshRate", 0 );
     QString glmode = config->readEntry("GLMode", "TFP" ).upper();
     if( glmode == "TFP" )
         glMode = GLTFP;

options.h

@@ -300,6 +300,7 @@ class Options : public KDecorationOptions
         uint dockShadowSize;
         bool onlyDecoTranslucent;
         
+        uint refreshRate;
         enum GLMode { GLTFP, GLSHM, GLFallback };
         GLMode glMode;
         bool glAlwaysRebind;

utils.cpp

@@ -45,6 +45,8 @@ namespace KWinInternal
 
 bool Extensions::has_shape = false;
 int Extensions::shape_event_base = 0;
+bool Extensions::has_randr = false;
+int Extensions::randr_event_base = 0;
 bool Extensions::has_damage = false;
 int Extensions::damage_event_base = 0;
 bool Extensions::has_composite = false;
@@ -55,6 +57,17 @@ void Extensions::init()
     {
     int dummy;
     has_shape = XShapeQueryExtension( display(), &shape_event_base, &dummy);
+#ifdef HAVE_XRANDR
+    has_randr = XRRQueryExtension( display(), &randr_event_base, &dummy );
+    if( has_randr )
+        {
+        int major, minor;
+        XRRQueryVersion( display(), &major, &minor );
+        has_randr = ( major > 1 || ( major == 1 && minor >= 1 ) );
+        }
+#else
+    has_randr = false;
+#endif
 #ifdef HAVE_XDAMAGE
     has_damage = XDamageQueryExtension( display(), &damage_event_base, &dummy );
 #else
@@ -99,6 +112,15 @@ bool Extensions::hasShape( Window w )
     return boundingShaped != 0;
     }
 
+int Extensions::randrNotifyEvent()
+    {
+#ifdef HAVE_XRANDR
+    return randr_event_base + RRScreenChangeNotify;
+#else
+    return 0;
+#endif
+    }
+
 int Extensions::damageNotifyEvent()
     {
 #ifdef HAVE_XDAMAGE

utils.h

@@ -17,6 +17,10 @@ License. See the file "COPYING" for the exact licensing terms.
 
 #include <X11/Xlib.h>
 
+#ifdef HAVE_XRANDR
+#include <X11/extensions/Xrandr.h>
+#endif
+
 #ifdef HAVE_XCOMPOSITE
 #include <X11/extensions/Xcomposite.h>
 #if XCOMPOSITE_MAJOR > 0 || XCOMPOSITE_MINOR >= 3
@@ -151,6 +155,8 @@ class Extensions
         static void init();
         static bool shapeAvailable() { return has_shape; }
         static int shapeNotifyEvent();
+        static bool randrAvailable() { return has_randr; }
+        static int randrNotifyEvent();
         static bool damageAvailable() { return has_damage; }
         static int damageNotifyEvent();
         static bool compositeAvailable() { return has_composite; }
@@ -160,6 +166,8 @@ class Extensions
     private:
         static bool has_shape;
         static int shape_event_base;
+        static bool has_randr;
+        static int randr_event_base;
         static bool has_damage;
         static int damage_event_base;
         static bool has_composite;