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authorLars Knoll <lars.knoll@nokia.com>2009-03-23 09:34:13 (GMT)
committerSimon Hausmann <simon.hausmann@nokia.com>2009-03-23 09:34:13 (GMT)
commit67ad0519fd165acee4a4d2a94fa502e9e4847bd0 (patch)
tree1dbf50b3dff8d5ca7e9344733968c72704eb15ff /src/opengl/qwindowsurface_gl.cpp
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Long live Qt!
Diffstat (limited to 'src/opengl/qwindowsurface_gl.cpp')
-rw-r--r--src/opengl/qwindowsurface_gl.cpp661
1 files changed, 661 insertions, 0 deletions
diff --git a/src/opengl/qwindowsurface_gl.cpp b/src/opengl/qwindowsurface_gl.cpp
new file mode 100644
index 0000000..3dd3064
--- /dev/null
+++ b/src/opengl/qwindowsurface_gl.cpp
@@ -0,0 +1,661 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the QtOpenGL module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui/QApplication>
+#include <QtGui/QColormap>
+#include <QtGui/QDesktopWidget>
+#include <QtGui/QPaintDevice>
+#include <QtGui/QWidget>
+
+#include <qglframebufferobject.h>
+#include <qglpixelbuffer.h>
+#include <qcolormap.h>
+#include <qdesktopwidget.h>
+#include "qdebug.h"
+
+#ifdef Q_WS_X11
+#include <private/qt_x11_p.h>
+#include <qx11info_x11.h>
+#include <private/qwidget_p.h>
+
+#ifndef QT_OPENGL_ES
+#include <GL/glx.h>
+#include <X11/Xlib.h>
+#endif
+#endif //Q_WS_X11
+
+#include <private/qglextensions_p.h>
+#include <private/qwindowsurface_gl_p.h>
+
+#include <private/qgl_p.h>
+
+#include <private/qglpixelbuffer_p.h>
+#include <private/qgraphicssystem_gl_p.h>
+#include <private/qpaintengine_opengl_p.h>
+
+#ifndef GLX_ARB_multisample
+#define GLX_SAMPLE_BUFFERS_ARB 100000
+#define GLX_SAMPLES_ARB 100001
+#endif
+
+QT_BEGIN_NAMESPACE
+
+//
+// QGLGraphicsSystem
+//
+#ifdef Q_WS_WIN
+Q_GUI_EXPORT bool qt_win_owndc_required;
+#endif
+QGLGraphicsSystem::QGLGraphicsSystem()
+ : QGraphicsSystem()
+{
+#if defined(Q_WS_X11) && !defined(QT_OPENGL_ES)
+ // only override the system defaults if the user hasn't already
+ // picked a visual
+ if (X11->visual == 0 && X11->visual_id == -1 && X11->visual_class == -1) {
+ // find a double buffered, RGBA visual that supports OpenGL
+ // and set that as the default visual for windows in Qt
+ int i = 0;
+ int spec[16];
+ spec[i++] = GLX_RGBA;
+#if 0
+ spec[i++] = GLX_DOUBLEBUFFER;
+ spec[i++] = GLX_DEPTH_SIZE;
+ spec[i++] = 8;
+ spec[i++] = GLX_STENCIL_SIZE;
+ spec[i++] = 8;
+ spec[i++] = GLX_SAMPLE_BUFFERS_ARB;
+ spec[i++] = 1;
+ spec[i++] = GLX_SAMPLES_ARB;
+ spec[i++] = 4;
+#endif
+ spec[i++] = XNone;
+
+ XVisualInfo *vi = glXChooseVisual(X11->display, X11->defaultScreen, spec);
+ if (vi) {
+ X11->visual_id = vi->visualid;
+ X11->visual_class = vi->c_class;
+
+ QGLFormat format;
+ int res;
+ glXGetConfig(X11->display, vi, GLX_LEVEL, &res);
+ format.setPlane(res);
+ glXGetConfig(X11->display, vi, GLX_DOUBLEBUFFER, &res);
+ format.setDoubleBuffer(res);
+ glXGetConfig(X11->display, vi, GLX_DEPTH_SIZE, &res);
+ format.setDepth(res);
+ if (format.depth())
+ format.setDepthBufferSize(res);
+ glXGetConfig(X11->display, vi, GLX_RGBA, &res);
+ format.setRgba(res);
+ glXGetConfig(X11->display, vi, GLX_RED_SIZE, &res);
+ format.setRedBufferSize(res);
+ glXGetConfig(X11->display, vi, GLX_GREEN_SIZE, &res);
+ format.setGreenBufferSize(res);
+ glXGetConfig(X11->display, vi, GLX_BLUE_SIZE, &res);
+ format.setBlueBufferSize(res);
+ glXGetConfig(X11->display, vi, GLX_ALPHA_SIZE, &res);
+ format.setAlpha(res);
+ if (format.alpha())
+ format.setAlphaBufferSize(res);
+ glXGetConfig(X11->display, vi, GLX_ACCUM_RED_SIZE, &res);
+ format.setAccum(res);
+ if (format.accum())
+ format.setAccumBufferSize(res);
+ glXGetConfig(X11->display, vi, GLX_STENCIL_SIZE, &res);
+ format.setStencil(res);
+ if (format.stencil())
+ format.setStencilBufferSize(res);
+ glXGetConfig(X11->display, vi, GLX_STEREO, &res);
+ format.setStereo(res);
+ glXGetConfig(X11->display, vi, GLX_SAMPLE_BUFFERS_ARB, &res);
+ format.setSampleBuffers(res);
+ if (format.sampleBuffers()) {
+ glXGetConfig(X11->display, vi, GLX_SAMPLES_ARB, &res);
+ format.setSamples(res);
+ }
+
+ QGLWindowSurface::surfaceFormat = format;
+ XFree(vi);
+
+ printf("using visual class %x, id %x\n", X11->visual_class, X11->visual_id);
+ }
+ }
+#elif defined(Q_WS_WIN)
+ QGLWindowSurface::surfaceFormat.setDoubleBuffer(false);
+
+ qt_win_owndc_required = true;
+#endif
+}
+
+//
+// QGLWindowSurface
+//
+
+class QGLGlobalShareWidget
+{
+public:
+ QGLGlobalShareWidget() : widget(0) {}
+
+ QGLWidget *shareWidget() {
+ if (!widget && !cleanedUp) {
+ widget = new QGLWidget;
+ }
+ return widget;
+ }
+
+ void cleanup() {
+ delete widget;
+ widget = 0;
+ cleanedUp = true;
+ }
+
+ static bool cleanedUp;
+
+private:
+ QGLWidget *widget;
+};
+
+bool QGLGlobalShareWidget::cleanedUp = false;
+
+static void qt_cleanup_gl_share_widget();
+Q_GLOBAL_STATIC_WITH_INITIALIZER(QGLGlobalShareWidget, _qt_gl_share_widget,
+ {
+ qAddPostRoutine(qt_cleanup_gl_share_widget);
+ })
+
+static void qt_cleanup_gl_share_widget()
+{
+ _qt_gl_share_widget()->cleanup();
+}
+
+QGLWidget* qt_gl_share_widget()
+{
+ if (QGLGlobalShareWidget::cleanedUp)
+ return 0;
+ return _qt_gl_share_widget()->shareWidget();
+}
+
+struct QGLWindowSurfacePrivate
+{
+ QGLFramebufferObject *fbo;
+ QGLPixelBuffer *pb;
+ GLuint tex_id;
+ GLuint pb_tex_id;
+
+ int tried_fbo : 1;
+ int tried_pb : 1;
+
+ QGLContext *ctx;
+
+ QList<QGLContext **> contexts;
+
+ QRegion paintedRegion;
+ QSize size;
+
+ QList<QImage> buffers;
+};
+
+QGLFormat QGLWindowSurface::surfaceFormat;
+
+QGLWindowSurface::QGLWindowSurface(QWidget *window)
+ : QWindowSurface(window), d_ptr(new QGLWindowSurfacePrivate)
+{
+ Q_ASSERT(window->isTopLevel());
+ QGLExtensions::init();
+ d_ptr->pb = 0;
+ d_ptr->fbo = 0;
+ d_ptr->ctx = 0;
+ d_ptr->tried_fbo = false;
+ d_ptr->tried_pb = false;
+}
+
+QGLWindowSurface::~QGLWindowSurface()
+{
+ if (d_ptr->ctx)
+ glDeleteTextures(1, &d_ptr->tex_id);
+ foreach(QGLContext **ctx, d_ptr->contexts) {
+ delete *ctx;
+ *ctx = 0;
+ }
+
+ delete d_ptr->pb;
+ delete d_ptr->fbo;
+ delete d_ptr;
+}
+
+void QGLWindowSurface::hijackWindow(QWidget *widget)
+{
+ QWidgetPrivate *widgetPrivate = widget->d_func();
+ widgetPrivate->createExtra();
+ if (widgetPrivate->extraData()->glContext)
+ return;
+
+ QGLContext *ctx = new QGLContext(surfaceFormat, widget);
+ ctx->create(qt_gl_share_widget()->context());
+#ifdef Q_WS_MAC
+ ctx->updatePaintDevice();
+#endif
+ widgetPrivate->extraData()->glContext = ctx;
+
+ union { QGLContext **ctxPtr; void **voidPtr; };
+
+ voidPtr = &widgetPrivate->extraData()->glContext;
+ d_ptr->contexts << ctxPtr;
+ qDebug() << "hijackWindow() context created for" << widget << d_ptr->contexts.size();
+}
+
+#if !defined(QT_OPENGL_ES_2)
+Q_GLOBAL_STATIC(QOpenGLPaintEngine, qt_gl_window_surface_paintengine)
+#endif
+
+/*! \reimp */
+QPaintEngine *QGLWindowSurface::paintEngine() const
+{
+#if !defined(QT_OPENGL_ES_2)
+ return qt_gl_window_surface_paintengine();
+#else
+ return 0;
+#endif
+}
+
+int QGLWindowSurface::metric(PaintDeviceMetric m) const
+{
+ return window()->metric(m);
+}
+
+QGLContext *QGLWindowSurface::context() const
+{
+ return d_ptr->ctx;
+}
+
+QPaintDevice *QGLWindowSurface::paintDevice()
+{
+ if (d_ptr->pb)
+ return d_ptr->pb;
+
+ if (d_ptr->ctx)
+ return this;
+
+ QGLContext *ctx = reinterpret_cast<QGLContext *>(window()->d_func()->extraData()->glContext);
+ ctx->makeCurrent();
+ return d_ptr->fbo;
+}
+
+static void drawTexture(const QRectF &rect, GLuint tex_id, const QSize &texSize, const QRectF &src = QRectF());
+
+void QGLWindowSurface::beginPaint(const QRegion &)
+{
+}
+
+void QGLWindowSurface::endPaint(const QRegion &rgn)
+{
+ if (context())
+ d_ptr->paintedRegion |= rgn;
+
+ d_ptr->buffers.clear();
+}
+
+void QGLWindowSurface::flush(QWidget *widget, const QRegion &rgn, const QPoint &offset)
+{
+ QWidget *parent = widget->internalWinId() ? widget : widget->nativeParentWidget();
+ Q_ASSERT(parent);
+
+ hijackWindow(parent);
+
+ QRect br = rgn.boundingRect().translated(offset);
+ br = br.intersected(window()->rect());
+ QPoint wOffset = qt_qwidget_data(parent)->wrect.topLeft();
+ QRect rect = br.translated(-offset - wOffset);
+
+ const GLenum target = qt_gl_preferredTextureTarget();
+
+ if (context()) {
+ context()->makeCurrent();
+
+ if (context()->format().doubleBuffer()) {
+ glBindTexture(target, d_ptr->tex_id);
+
+ QVector<QRect> rects = d_ptr->paintedRegion.rects();
+ for (int i = 0; i < rects.size(); ++i) {
+ QRect br = rects.at(i);
+ if (br.isEmpty())
+ continue;
+
+ const uint bottom = window()->height() - (br.y() + br.height());
+ glCopyTexSubImage2D(target, 0, br.x(), bottom, br.x(), bottom, br.width(), br.height());
+ }
+
+ glBindTexture(target, 0);
+
+ QRegion dirtyRegion = QRegion(window()->rect()) - d_ptr->paintedRegion;
+
+ if (!dirtyRegion.isEmpty()) {
+ context()->makeCurrent();
+
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+#ifndef QT_OPENGL_ES
+ glOrtho(0, window()->width(), window()->height(), 0, -999999, 999999);
+#else
+ glOrthof(0, window()->width(), window()->height(), 0, -999999, 999999);
+#endif
+ glViewport(0, 0, window()->width(), window()->height());
+
+ QVector<QRect> rects = dirtyRegion.rects();
+ glColor4f(1, 1, 1, 1);
+ for (int i = 0; i < rects.size(); ++i) {
+ QRect rect = rects.at(i);
+ if (rect.isEmpty())
+ continue;
+
+ drawTexture(rect, d_ptr->tex_id, window()->size(), rect);
+ }
+ }
+ d_ptr->paintedRegion = QRegion();
+
+ context()->swapBuffers();
+ } else {
+ glFlush();
+ }
+
+ return;
+ }
+
+ QGLContext *ctx = reinterpret_cast<QGLContext *>(parent->d_func()->extraData()->glContext);
+ GLuint texture;
+ if (d_ptr->fbo) {
+ texture = d_ptr->fbo->texture();
+ } else {
+ d_ptr->pb->makeCurrent();
+ glBindTexture(target, d_ptr->pb_tex_id);
+ const uint bottom = window()->height() - (br.y() + br.height());
+ glCopyTexSubImage2D(target, 0, br.x(), bottom, br.x(), bottom, br.width(), br.height());
+ texture = d_ptr->pb_tex_id;
+ glBindTexture(target, 0);
+ }
+
+ QSize size = widget->rect().size();
+ if (ctx->format().doubleBuffer()) {
+ rect = parent->rect();
+ br = rect.translated(wOffset);
+ size = parent->size();
+ }
+
+ ctx->makeCurrent();
+#ifdef Q_WS_MAC
+ ctx->updatePaintDevice();
+#endif
+ if (d_ptr->fbo)
+ d_ptr->fbo->release();
+
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+#ifndef QT_OPENGL_ES
+ glOrtho(0, size.width(), size.height(), 0, -999999, 999999);
+#else
+ glOrthof(0, size.width(), size.height(), 0, -999999, 999999);
+#endif
+ glViewport(0, 0, size.width(), size.height());
+
+ glColor4f(1, 1, 1, 1);
+ drawTexture(rect, texture, window()->size(), br);
+
+ if (ctx->format().doubleBuffer())
+ ctx->swapBuffers();
+ else
+ glFlush();
+
+ if (d_ptr->fbo)
+ d_ptr->fbo->bind();
+}
+
+void QGLWindowSurface::setGeometry(const QRect &rect)
+{
+ QWindowSurface::setGeometry(rect);
+
+ const GLenum target = qt_gl_preferredTextureTarget();
+
+ if (rect.width() <= 0 || rect.height() <= 0)
+ return;
+
+ if (d_ptr->size == rect.size())
+ return;
+
+ d_ptr->size = rect.size();
+
+ if (d_ptr->ctx) {
+ glBindTexture(target, d_ptr->tex_id);
+ glTexImage2D(target, 0, GL_RGBA, rect.width(), rect.height(), 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
+ glBindTexture(target, 0);
+ return;
+ }
+
+ if (d_ptr->pb || !d_ptr->tried_pb) {
+ d_ptr->tried_pb = true;
+
+ if (d_ptr->pb) {
+ d_ptr->pb->makeCurrent();
+ glDeleteTextures(1, &d_ptr->pb_tex_id);
+ }
+
+ delete d_ptr->pb;
+
+ d_ptr->pb = new QGLPixelBuffer(rect.width(), rect.height(),
+ QGLFormat(QGL::SampleBuffers | QGL::StencilBuffer | QGL::DepthBuffer),
+ qt_gl_share_widget());
+
+ if (d_ptr->pb->isValid()) {
+ qDebug() << "PB Sample buffers:" << d_ptr->pb->format().sampleBuffers();
+ d_ptr->pb->makeCurrent();
+
+ glGenTextures(1, &d_ptr->pb_tex_id);
+ glBindTexture(target, d_ptr->pb_tex_id);
+ glTexImage2D(target, 0, GL_RGBA, rect.width(), rect.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
+
+ glTexParameterf(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+ glTexParameterf(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+ glBindTexture(target, 0);
+
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+#ifndef QT_OPENGL_ES
+ glOrtho(0, d_ptr->pb->width(), d_ptr->pb->height(), 0, -999999, 999999);
+#else
+ glOrthof(0, d_ptr->pb->width(), d_ptr->pb->height(), 0, -999999, 999999);
+#endif
+
+ d_ptr->pb->d_ptr->qctx->d_func()->internal_context = true;
+ return;
+ } else {
+ qDebug() << "QGLWindowSurface: Failed to create valid pixelbuffer, falling back";
+ delete d_ptr->pb;
+ d_ptr->pb = 0;
+ }
+ }
+
+ if ((QGLExtensions::glExtensions & QGLExtensions::FramebufferObject) && (d_ptr->fbo || !d_ptr->tried_fbo)) {
+ d_ptr->tried_fbo = true;
+ hijackWindow(window());
+ QGLContext *ctx = reinterpret_cast<QGLContext *>(window()->d_func()->extraData()->glContext);
+ ctx->d_ptr->internal_context = true;
+ ctx->makeCurrent();
+ delete d_ptr->fbo;
+ d_ptr->fbo = new QGLFramebufferObject(rect.size(), QGLFramebufferObject::CombinedDepthStencil,
+ GLenum(target), GLenum(GL_RGBA));
+
+ d_ptr->fbo->bind();
+ if (d_ptr->fbo->isValid()) {
+ return;
+ } else {
+ qDebug() << "QGLWindowSurface: Failed to create valid FBO, falling back";
+ delete d_ptr->fbo;
+ d_ptr->fbo = 0;
+ }
+ }
+
+ hijackWindow(window());
+ QGLContext *ctx = reinterpret_cast<QGLContext *>(window()->d_func()->extraData()->glContext);
+ ctx->makeCurrent();
+
+ glGenTextures(1, &d_ptr->tex_id);
+ glBindTexture(target, d_ptr->tex_id);
+ glTexImage2D(target, 0, GL_RGBA, rect.width(), rect.height(), 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
+
+ glTexParameterf(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+ glTexParameterf(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+ glBindTexture(target, 0);
+
+ qDebug() << "QGLWindowSurface: Using plain widget as window surface" << this;;
+ d_ptr->ctx = ctx;
+ d_ptr->ctx->d_ptr->internal_context = true;
+}
+
+bool QGLWindowSurface::scroll(const QRegion &area, int dx, int dy)
+{
+ // this code randomly fails currently for unknown reasons
+ return false;
+
+ if (!d_ptr->pb)
+ return false;
+
+ d_ptr->pb->makeCurrent();
+
+ QRect br = area.boundingRect();
+
+#if 0
+ // ## workaround driver issue (scrolling by these deltas is unbearably slow for some reason)
+ // ## maybe we should use glCopyTexSubImage insteadk
+ if (dx == 1 || dx == -1 || dy == 1 || dy == -1 || dy == 2)
+ return false;
+
+ glRasterPos2i(br.x() + dx, br.y() + br.height() + dy);
+ glCopyPixels(br.x(), d_ptr->pb->height() - (br.y() + br.height()), br.width(), br.height(), GL_COLOR);
+ return true;
+#endif
+
+ const GLenum target = qt_gl_preferredTextureTarget();
+
+ glBindTexture(target, d_ptr->tex_id);
+ glCopyTexImage2D(target, 0, GL_RGBA, br.x(), d_ptr->pb->height() - (br.y() + br.height()), br.width(), br.height(), 0);
+ glBindTexture(target, 0);
+
+ drawTexture(br.translated(dx, dy), d_ptr->tex_id, window()->size());
+
+ return true;
+}
+
+static void drawTexture(const QRectF &rect, GLuint tex_id, const QSize &texSize, const QRectF &br)
+{
+ const GLenum target = qt_gl_preferredTextureTarget();
+ QRectF src = br.isEmpty()
+ ? QRectF(QPointF(), texSize)
+ : QRectF(QPointF(br.x(), texSize.height() - br.bottom()), br.size());
+
+ if (target == GL_TEXTURE_2D) {
+ qreal width = texSize.width();
+ qreal height = texSize.height();
+
+ src.setLeft(src.left() / width);
+ src.setRight(src.right() / width);
+ src.setTop(src.top() / height);
+ src.setBottom(src.bottom() / height);
+ }
+
+ const q_vertexType tx1 = f2vt(src.left());
+ const q_vertexType tx2 = f2vt(src.right());
+ const q_vertexType ty1 = f2vt(src.top());
+ const q_vertexType ty2 = f2vt(src.bottom());
+
+ q_vertexType texCoordArray[4*2] = {
+ tx1, ty2, tx2, ty2, tx2, ty1, tx1, ty1
+ };
+
+ q_vertexType vertexArray[4*2];
+ extern void qt_add_rect_to_array(const QRectF &r, q_vertexType *array); // qpaintengine_opengl.cpp
+ qt_add_rect_to_array(rect, vertexArray);
+
+ glVertexPointer(2, q_vertexTypeEnum, 0, vertexArray);
+ glTexCoordPointer(2, q_vertexTypeEnum, 0, texCoordArray);
+
+ glBindTexture(target, tex_id);
+ glEnable(target);
+
+ glEnableClientState(GL_VERTEX_ARRAY);
+ glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+ glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+ glDisableClientState(GL_VERTEX_ARRAY);
+ glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+
+ glDisable(target);
+ glBindTexture(target, 0);
+}
+
+QImage *QGLWindowSurface::buffer(const QWidget *widget)
+{
+ QImage image;
+
+ if (d_ptr->pb)
+ image = d_ptr->pb->toImage();
+ else if (d_ptr->fbo)
+ image = d_ptr->fbo->toImage();
+
+ if (image.isNull())
+ return 0;
+
+ QRect rect = widget->rect();
+ rect.translate(widget->mapTo(widget->window(), QPoint()));
+
+ QImage subImage = image.copy(rect);
+ d_ptr->buffers << subImage;
+ return &d_ptr->buffers.last();
+}
+
+
+
+QT_END_NAMESPACE
+