/***************************************************************** KWin - the KDE window manager This file is part of the KDE project. Copyright (C) 2006 Lubos Lunak You can Freely distribute this program under the GNU General Public License. See the file "COPYING" for the exact licensing terms. ******************************************************************/ /* (NOTE: The compositing code is work in progress. As such this design documentation may get outdated in some areas.) The base class for compositing, implementing shared functionality between the OpenGL and XRender backends. Design: When compositing is turned on, XComposite extension is used to redirect drawing of windows to pixmaps and XDamage extension is used to get informed about damage (changes) to window contents. This code is mostly in composite.cpp . Workspace::performCompositing() starts one painting pass. Painting is done by painting the screen, which in turn paints every window. Painting can be affected using effects, which are chained. E.g. painting a screen means that actually paintScreen() of the first effect is called, which possibly does modifications and calls next effect's paintScreen() and so on, until Scene::finalPaintScreen() is called. There are 3 phases of every paint (not necessarily done together): The pre-paint phase, the paint phase and the post-paint phase. The pre-paint phase is used to find out about how the painting will be actually done (i.e. what the effects will do). For example when only a part of the screen needs to be updated and no effect will do any transformation it is possible to use an optimized paint function. How the painting will be done is controlled by the mask argument, see PAINT_WINDOW_* and PAINT_SCREEN_* flags in scene.h . For example an effect that decides to paint a normal windows as translucent will need to modify the mask in its prePaintWindow() to include the PAINT_WINDOW_TRANSLUCENT flag. The paintWindow() function will then get the mask with this flag turned on and will also paint using transparency. The paint pass does the actual painting, based on the information collected using the pre-paint pass. After running through the effects' paintScreen() either paintGenericScreen() or optimized paintSimpleScreen() are called. Those call paintWindow() on windows (not necessarily all), possibly using clipping to optimize performance and calling paintWindow() first with only PAINT_WINDOW_OPAQUE to paint the opaque parts and then later with PAINT_WINDOW_TRANSLUCENT to paint the transparent parts. Function paintWindow() again goes through effects' paintWindow() until finalPaintWindow() is called, which calls the window's performPaint() to do the actual painting. The post-paint can be used for cleanups and is also used for scheduling repaints during the next painting pass for animations. Effects wanting to repaint certain parts can manually damage them during post-paint and repaint of these parts will be done during the next paint pass. */ #include "scene.h" #include #include "client.h" #include "deleted.h" #include "effects.h" namespace KWinInternal { //**************************************** // Scene //**************************************** Scene* scene; Scene::Scene( Workspace* ws ) : wspace( ws ), has_waitSync( false ) { } Scene::~Scene() { } // returns mask and possibly modified region void Scene::paintScreen( int* mask, QRegion* region ) { *mask = ( *region == QRegion( 0, 0, displayWidth(), displayHeight())) ? 0 : PAINT_SCREEN_REGION; updateTimeDiff(); // preparation step effects->startPaint(); effects->prePaintScreen( mask, region, time_diff ); if( *mask & ( PAINT_SCREEN_TRANSFORMED | PAINT_WINDOW_TRANSFORMED )) { // Region painting is not possible with transformations, // because screen damage doesn't match transformed positions. *mask &= ~PAINT_SCREEN_REGION; *region = infiniteRegion(); } else if( *mask & PAINT_SCREEN_REGION ) { // make sure not to go outside visible screen *region &= QRegion( 0, 0, displayWidth(), displayHeight()); } else { // whole screen, not transformed, force region to be full *region = QRegion( 0, 0, displayWidth(), displayHeight()); } if( *mask & PAINT_SCREEN_BACKGROUND_FIRST ) paintBackground( *region ); ScreenPaintData data; effects->paintScreen( *mask, *region, data ); effects->postPaintScreen(); foreach( Window* w, stacking_order ) effects->postPaintWindow( effectWindow( w )); } // Compute time since the last painting pass. void Scene::updateTimeDiff() { if( last_time.isNull()) { // Painting has been idle (optimized out) for some time, // which means time_diff would be huge and would break animations. // Simply set it to zero. time_diff = 0; } else time_diff = last_time.elapsed(); if( time_diff < 0 ) // check time rollback time_diff = 0; last_time.start();; } // Painting pass is optimized away. void Scene::idle() { // Don't break time since last paint for the next pass. last_time = QTime(); } // the function that'll be eventually called by paintScreen() above void Scene::finalPaintScreen( int mask, QRegion region, ScreenPaintData& data ) { if( mask & ( PAINT_SCREEN_TRANSFORMED | PAINT_WINDOW_TRANSFORMED )) paintGenericScreen( mask, data ); else paintSimpleScreen( mask, region ); } // The generic painting code that can handle even transformations. // It simply paints bottom-to-top. void Scene::paintGenericScreen( int orig_mask, ScreenPaintData ) { if( !( orig_mask & PAINT_SCREEN_BACKGROUND_FIRST )) paintBackground( infiniteRegion()); foreach( Window* w, stacking_order ) // bottom to top { int mask = orig_mask | ( w->isOpaque() ? PAINT_WINDOW_OPAQUE : PAINT_WINDOW_TRANSLUCENT ); if( !w->isVisible()) mask |= PAINT_WINDOW_DISABLED; QRegion damage = infiniteRegion(); // preparation step effects->prePaintWindow( effectWindow( w ), &mask, &damage, time_diff ); if( mask & PAINT_WINDOW_DISABLED ) continue; paintWindow( w, mask, damage ); } } // The optimized case without any transformations at all. // It can paint only the requested region and can use clipping // to reduce painting and improve performance. void Scene::paintSimpleScreen( int orig_mask, QRegion region ) { // TODO PAINT_WINDOW_* flags don't belong here, that's why it's in the assert, // perhaps the two enums should be separated assert(( orig_mask & ( PAINT_WINDOW_TRANSFORMED | PAINT_SCREEN_TRANSFORMED | PAINT_WINDOW_TRANSLUCENT | PAINT_WINDOW_OPAQUE )) == 0 ); QList< Phase2Data > phase2; // Draw each opaque window top to bottom, subtracting the bounding rect of // each window from the clip region after it's been drawn. for( int i = stacking_order.count() - 1; // top to bottom i >= 0; --i ) { Window* w = stacking_order[ i ]; if( region.isEmpty()) // completely clipped continue; int mask = orig_mask | ( w->isOpaque() ? PAINT_WINDOW_OPAQUE : PAINT_WINDOW_TRANSLUCENT ); if( !w->isVisible()) mask |= PAINT_WINDOW_DISABLED; QRegion damage = region; // preparation step effects->prePaintWindow( effectWindow( w ), &mask, &damage, time_diff ); if( mask & PAINT_WINDOW_DISABLED ) continue; // If the window is transparent, the transparent part will be done // in the 2nd pass. if( mask & PAINT_WINDOW_TRANSLUCENT ) phase2.prepend( Phase2Data( w, region, mask )); if( mask & PAINT_WINDOW_OPAQUE ) { paintWindow( w, mask, region ); // If the window is not transparent at all, it can clip windows below. if( ( mask & PAINT_WINDOW_TRANSLUCENT ) == 0 ) region -= w->shape().translated( w->x(), w->y()); } } if( !( orig_mask & PAINT_SCREEN_BACKGROUND_FIRST )) paintBackground( region ); // Fill any areas of the root window not covered by windows // Now walk the list bottom to top, drawing translucent windows. // That we draw bottom to top is important now since we're drawing translucent objects // and also are clipping only by opaque windows. foreach( Phase2Data d, phase2 ) { Window* w = d.window; paintWindow( w, d.mask, d.region ); } } void Scene::paintWindow( Window* w, int mask, QRegion region ) { WindowPaintData data; data.opacity = w->window()->opacity(); w->prepareForPainting(); effects->paintWindow( effectWindow( w ), mask, region, data ); } // the function that'll be eventually called by paintWindow() above void Scene::finalPaintWindow( EffectWindow* w, int mask, QRegion region, WindowPaintData& data ) { w->sceneWindow()->performPaint( mask, region, data ); } //**************************************** // Scene::Window //**************************************** Scene::Window::Window( Toplevel * c ) : toplevel( c ) , shape_valid( false ) { } Scene::Window::~Window() { } void Scene::Window::free() { } void Scene::Window::discardShape() { // it is created on-demand and cached, simply // reset the flag shape_valid = false; } // Find out the shape of the window using the XShape extension // or if not shape is set then simply it's the window geometry. QRegion Scene::Window::shape() const { if( !shape_valid ) { Client* c = dynamic_cast< Client* >( toplevel ); if( toplevel->shape() || ( c != NULL && !c->mask().isEmpty())) { int count, order; XRectangle* rects = XShapeGetRectangles( display(), toplevel->handle(), ShapeBounding, &count, &order ); if(rects) { shape_region = QRegion(); for( int i = 0; i < count; ++i ) shape_region += QRegion( rects[ i ].x, rects[ i ].y, rects[ i ].width, rects[ i ].height ); XFree(rects); } else shape_region = QRegion( 0, 0, width(), height()); } else shape_region = QRegion( 0, 0, width(), height()); shape_valid = true; } return shape_region; } bool Scene::Window::isVisible() const { if( dynamic_cast< Deleted* >( toplevel ) != NULL ) return false; if( !toplevel->isOnCurrentDesktop()) return false; if( Client* c = dynamic_cast< Client* >( toplevel )) return c->isShown( true ); return true; // Unmanaged is always visible // TODO there may be transformations, so ignore this for now return !toplevel->geometry() .intersect( QRect( 0, 0, displayWidth(), displayHeight())) .isEmpty(); } bool Scene::Window::isOpaque() const { return toplevel->opacity() == 1.0 && !toplevel->hasAlpha(); } } // namespace