path: root/src/opengl/qopenglcompositor.cpp

// Copyright (C) 2016 The Qt Company Ltd.// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only#include <QtOpenGL/QOpenGLFramebufferObject>#include <QtGui/QOpenGLContext>#include <QtGui/QWindow>#include <rhi/qrhi.h>#include <qpa/qplatformbackingstore.h>#include"qopenglcompositor_p.h" QT_BEGIN_NAMESPACE /*! \class QOpenGLCompositor \brief A generic OpenGL-based compositor \since 5.4 \internal \ingroup qpa This class provides a lightweight compositor that maintains the basic stacking order of windows and composites them by drawing textured quads via OpenGL. It it meant to be used by platform plugins that run without a windowing system. It is up to the platform plugin to manage the lifetime of the compositor (instance(), destroy()), set the correct destination context and window as early as possible (setTarget()), register the composited windows as they are shown, activated, raised and lowered (addWindow(), moveToTop(), etc.), and to schedule repaints (update()). \note To get support for QWidget-based windows, just use QOpenGLCompositorBackingStore. It will automatically create textures from the raster-rendered content and trigger the necessary repaints. */static QOpenGLCompositor *compositor =0;QOpenGLCompositor::QOpenGLCompositor():m_context(0),m_targetWindow(0),m_rotation(0){Q_ASSERT(!compositor); m_updateTimer.setSingleShot(true); m_updateTimer.setInterval(0);connect(&m_updateTimer,SIGNAL(timeout()),SLOT(handleRenderAllRequest()));}QOpenGLCompositor::~QOpenGLCompositor(){Q_ASSERT(compositor ==this); m_blitter.destroy(); compositor =0;}voidQOpenGLCompositor::setTargetWindow(QWindow *targetWindow,const QRect &nativeTargetGeometry){ m_targetWindow = targetWindow; m_nativeTargetGeometry = nativeTargetGeometry;}voidQOpenGLCompositor::setTargetContext(QOpenGLContext *context){ m_context = context;}voidQOpenGLCompositor::setRotation(int degrees){ m_rotation = degrees; m_rotationMatrix.setToIdentity(); m_rotationMatrix.rotate(degrees,0,0,1);}voidQOpenGLCompositor::update(){if(!m_updateTimer.isActive()) m_updateTimer.start();} QImage QOpenGLCompositor::grab(){Q_ASSERT(m_context && m_targetWindow); QOpenGLFramebufferObject fbo(m_nativeTargetGeometry.size());grabToFrameBufferObject(&fbo);return fbo.toImage();}boolQOpenGLCompositor::grabToFrameBufferObject(QOpenGLFramebufferObject *fbo, GrabOrientation orientation){Q_ASSERT(fbo);if(fbo->size() != m_nativeTargetGeometry.size()|| fbo->format().textureTarget() != GL_TEXTURE_2D)return false; m_context->makeCurrent(m_targetWindow);renderAll(fbo, orientation == Flipped ?QOpenGLTextureBlitter::OriginTopLeft :QOpenGLTextureBlitter::OriginBottomLeft);return true;}voidQOpenGLCompositor::handleRenderAllRequest(){Q_ASSERT(m_context && m_targetWindow); m_context->makeCurrent(m_targetWindow);renderAll(0);}voidQOpenGLCompositor::renderAll(QOpenGLFramebufferObject *fbo,QOpenGLTextureBlitter::Origin origin){if(fbo) fbo->bind();glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);glViewport(0,0, m_nativeTargetGeometry.width(), m_nativeTargetGeometry.height());if(!m_blitter.isCreated()) m_blitter.create(); m_blitter.bind();for(int i =0; i < m_windows.size(); ++i) m_windows.at(i)->beginCompositing();for(int i =0; i < m_windows.size(); ++i)render(m_windows.at(i), origin); m_blitter.release();if(!fbo) m_context->swapBuffers(m_targetWindow);else fbo->release();for(int i =0; i < m_windows.size(); ++i) m_windows.at(i)->endCompositing();}struct BlendStateBinder {BlendStateBinder() :m_blend(false) {glDisable(GL_BLEND);}voidset(bool blend) {if(blend != m_blend) {if(blend) {glEnable(GL_BLEND);glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);}else{glDisable(GL_BLEND);} m_blend = blend;}}~BlendStateBinder() {if(m_blend)glDisable(GL_BLEND);}bool m_blend;};staticinline QRect toBottomLeftRect(const QRect &topLeftRect,int windowHeight){returnQRect(topLeftRect.x(), windowHeight - topLeftRect.bottomRight().y() -1, topLeftRect.width(), topLeftRect.height());}static voidclippedBlit(const QPlatformTextureList *textures,int idx,const QRect &sourceWindowRect,const QRect &targetWindowRect, QOpenGLTextureBlitter *blitter, QMatrix4x4 *rotationMatrix,QOpenGLTextureBlitter::Origin sourceOrigin){const QRect clipRect = textures->clipRect(idx);if(clipRect.isEmpty())return;const QRect rectInWindow = textures->geometry(idx).translated(sourceWindowRect.topLeft());const QRect clippedRectInWindow = rectInWindow & clipRect.translated(rectInWindow.topLeft());const QRect srcRect =toBottomLeftRect(clipRect, rectInWindow.height()); QMatrix4x4 target =QOpenGLTextureBlitter::targetTransform(clippedRectInWindow, targetWindowRect);if(rotationMatrix) target = *rotationMatrix * target;const QMatrix3x3 source =QOpenGLTextureBlitter::sourceTransform(srcRect, rectInWindow.size(), sourceOrigin);const uint textureId = textures->texture(idx)->nativeTexture().object; blitter->blit(textureId, target, source);}voidQOpenGLCompositor::render(QOpenGLCompositorWindow *window,QOpenGLTextureBlitter::Origin origin){const QPlatformTextureList *textures = window->textures();if(!textures)return;const QRect targetWindowRect(QPoint(0,0), m_targetWindow->geometry().size());float currentOpacity =1.0f; BlendStateBinder blend;const QRect sourceWindowRect = window->sourceWindow()->geometry();auto clippedBlitSourceOrigin = origin ==QOpenGLTextureBlitter::OriginTopLeft ?QOpenGLTextureBlitter::OriginBottomLeft :QOpenGLTextureBlitter::OriginTopLeft;for(int i =0; i < textures->count(); ++i) {const uint textureId = textures->texture(i)->nativeTexture().object;const float opacity = window->sourceWindow()->opacity();if(opacity != currentOpacity) { currentOpacity = opacity; m_blitter.setOpacity(currentOpacity);}if(textures->count() >1&& i == textures->count() -1) {// Backingstore for a widget with QOpenGLWidget subwidgets blend.set(true); QMatrix4x4 target =QOpenGLTextureBlitter::targetTransform(textures->geometry(i), targetWindowRect);if(m_rotation) target = m_rotationMatrix * target; m_blitter.blit(textureId, target, origin);}else if(textures->count() ==1) {// A regular QWidget windowconst bool translucent = window->sourceWindow()->requestedFormat().alphaBufferSize() >0; blend.set(translucent); QMatrix4x4 target =QOpenGLTextureBlitter::targetTransform(textures->geometry(i), targetWindowRect);if(m_rotation) target = m_rotationMatrix * target; m_blitter.blit(textureId, target, origin);}else if(!textures->flags(i).testFlag(QPlatformTextureList::StacksOnTop)) {// Texture from an FBO belonging to a QOpenGLWidget or QQuickWidget blend.set(false);clippedBlit(textures, i, sourceWindowRect, targetWindowRect, &m_blitter, m_rotation ? &m_rotationMatrix :nullptr, clippedBlitSourceOrigin);}}for(int i =0; i < textures->count(); ++i) {if(textures->flags(i).testFlag(QPlatformTextureList::StacksOnTop)) { blend.set(true);clippedBlit(textures, i, sourceWindowRect, targetWindowRect, &m_blitter, m_rotation ? &m_rotationMatrix :nullptr, clippedBlitSourceOrigin);}} m_blitter.setOpacity(1.0f);} QOpenGLCompositor *QOpenGLCompositor::instance(){if(!compositor) compositor =new QOpenGLCompositor;return compositor;}voidQOpenGLCompositor::destroy(){delete compositor; compositor =0;}voidQOpenGLCompositor::addWindow(QOpenGLCompositorWindow *window){if(!m_windows.contains(window)) { m_windows.append(window);ensureCorrectZOrder();if(window == m_windows.constLast()) emit topWindowChanged(window);}}voidQOpenGLCompositor::removeWindow(QOpenGLCompositorWindow *window){bool couldChangeTopWindow = (m_windows.size() >1) ? (window == m_windows.constLast()) :false;if(m_windows.removeOne(window) && couldChangeTopWindow) emit topWindowChanged(m_windows.constLast());}voidQOpenGLCompositor::moveToTop(QOpenGLCompositorWindow *window){if(!m_windows.isEmpty() && window == m_windows.constLast()) {// Already on topreturn;} m_windows.removeOne(window); m_windows.append(window);ensureCorrectZOrder();if(window == m_windows.constLast()) emit topWindowChanged(window);}voidQOpenGLCompositor::changeWindowIndex(QOpenGLCompositorWindow *window,int newIdx){int idx = m_windows.indexOf(window);if(idx != -1&& idx != newIdx) { m_windows.move(idx, newIdx);ensureCorrectZOrder();if(window == m_windows.constLast()) emit topWindowChanged(m_windows.last());}}voidQOpenGLCompositor::ensureCorrectZOrder(){constauto originalOrder = m_windows;std::sort(m_windows.begin(), m_windows.end(),[this, &originalOrder](QOpenGLCompositorWindow *cw1, QOpenGLCompositorWindow *cw2) { QWindow *w1 = cw1->sourceWindow(); QWindow *w2 = cw2->sourceWindow();// Case #1: The main window needs to have less z-order. It can never be in// front of our tool windows, popups etc, because it's fullscreen!if(w1 == m_targetWindow || w2 == m_targetWindow)return w1 == m_targetWindow;// Case #2:if(w2->isAncestorOf(w1)) {// w1 is transient child of w2. W1 goes in front then.return false;}if(w1->isAncestorOf(w2)) {// Or the other way aroundreturn true;}// Case #3: Modality gets higher Zif(w1->modality() !=Qt::NonModal && w2->modality() ==Qt::NonModal)return false;if(w2->modality() !=Qt::NonModal && w1->modality() ==Qt::NonModal)return true;const bool isTool1 = (w1->flags() &Qt::Tool) ==Qt::Tool;const bool isTool2 = (w2->flags() &Qt::Tool) ==Qt::Tool;const bool isPurePopup1 = !isTool1 && (w1->flags() &Qt::Popup) ==Qt::Popup;const bool isPurePopup2 = !isTool2 && (w2->flags() &Qt::Popup) ==Qt::Popup;// Case #4: By pure-popup we mean menus and tooltips. Qt::Tool implies Qt::Popup// and we don't want to catch QDockWidget and other tool windows just yetif(isPurePopup1 != isPurePopup2)return!isPurePopup1;// Case #5: One of the window is a Tool, that goes to front, as done in other QPAsif(isTool1 != isTool2)return!isTool1;// Case #6: Just preserve original sorting:return originalOrder.indexOf(cw1) < originalOrder.indexOf(cw2);});} QT_END_NAMESPACE #include"moc_qopenglcompositor_p.cpp"