src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,2208 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (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 Technology Preview License Agreement accompanying
+** this package.
+**
+** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*
+    When the active program changes, we need to update it's uniforms.
+    We could track state for each program and only update stale uniforms
+        - Could lead to lots of overhead if there's a lot of programs
+    We could update all the uniforms when the program changes
+        - Could end up updating lots of uniforms which don't need updating
+
+    Updating uniforms should be cheap, so the overhead of updating up-to-date
+    uniforms should be minimal. It's also less complex.
+
+    Things which _may_ cause a different program to be used:
+        - Change in brush/pen style
+        - Change in painter opacity
+        - Change in composition mode
+
+    Whenever we set a mode on the shader manager - it needs to tell us if it had
+    to switch to a different program.
+
+    The shader manager should only switch when we tell it to. E.g. if we set a new
+    brush style and then switch to transparent painter, we only want it to compile
+    and use the correct program when we really need it.
+*/
+
+#include "qpaintengineex_opengl2_p.h"
+
+#include <string.h> //for memcpy
+#include <qmath.h>
+
+#include <private/qgl_p.h>
+#include <private/qmath_p.h>
+#include <private/qpaintengineex_p.h>
+#include <QPaintEngine>
+#include <private/qpainter_p.h>
+#include <private/qfontengine_p.h>
+#include <private/qtextureglyphcache_p.h>
+#include <private/qpixmapdata_gl_p.h>
+#include <private/qdatabuffer_p.h>
+
+#include "qglgradientcache_p.h"
+#include "qglengineshadermanager_p.h"
+#include "qgl2pexvertexarray_p.h"
+
+#include "qtriangulatingstroker_p.h"
+
+#include <QDebug>
+
+QT_BEGIN_NAMESPACE
+
+//#define QT_GL_NO_SCISSOR_TEST
+
+static const GLuint GL_STENCIL_HIGH_BIT         = 0x80;
+static const GLuint QT_BRUSH_TEXTURE_UNIT       = 0;
+static const GLuint QT_IMAGE_TEXTURE_UNIT       = 0; //Can be the same as brush texture unit
+static const GLuint QT_MASK_TEXTURE_UNIT        = 1;
+static const GLuint QT_BACKGROUND_TEXTURE_UNIT  = 2;
+
+#ifdef Q_WS_WIN
+extern Q_GUI_EXPORT bool qt_cleartype_enabled;
+#endif
+
+class QGLTextureGlyphCache : public QObject, public QTextureGlyphCache
+{
+    Q_OBJECT
+public:
+    QGLTextureGlyphCache(QGLContext *context, QFontEngineGlyphCache::Type type, const QTransform &matrix);
+    ~QGLTextureGlyphCache();
+
+    virtual void createTextureData(int width, int height);
+    virtual void resizeTextureData(int width, int height);
+    virtual void fillTexture(const Coord &c, glyph_t glyph);
+    virtual int glyphMargin() const;
+
+    inline GLuint texture() const { return m_texture; }
+
+    inline int width() const { return m_width; }
+    inline int height() const { return m_height; }
+
+    inline void setPaintEnginePrivate(QGL2PaintEngineExPrivate *p) { pex = p; }
+
+
+public Q_SLOTS:
+    void contextDestroyed(const QGLContext *context) {
+        if (context == ctx) {
+            QList<const QGLContext *> shares = qgl_share_reg()->shares(ctx);
+            if (shares.isEmpty()) {
+                glDeleteFramebuffers(1, &m_fbo);
+                if (m_width || m_height)
+                    glDeleteTextures(1, &m_texture);
+                ctx = 0;
+            } else {
+                // since the context holding the texture is shared, and
+                // about to be destroyed, we have to transfer ownership
+                // of the texture to one of the share contexts
+                ctx = const_cast<QGLContext *>((ctx == shares.at(0)) ? shares.at(1) : shares.at(0));
+            }
+        }
+    }
+
+private:
+    QGLContext *ctx;
+
+    QGL2PaintEngineExPrivate *pex;
+
+    GLuint m_texture;
+    GLuint m_fbo;
+
+    int m_width;
+    int m_height;
+
+    QGLShaderProgram *m_program;
+};
+
+QGLTextureGlyphCache::QGLTextureGlyphCache(QGLContext *context, QFontEngineGlyphCache::Type type, const QTransform &matrix)
+    : QTextureGlyphCache(type, matrix)
+    , ctx(context)
+    , m_width(0)
+    , m_height(0)
+{
+    glGenFramebuffers(1, &m_fbo);
+    connect(QGLSignalProxy::instance(), SIGNAL(aboutToDestroyContext(const QGLContext *)),
+            SLOT(contextDestroyed(const QGLContext *)));
+}
+
+QGLTextureGlyphCache::~QGLTextureGlyphCache()
+{
+    if (ctx) {
+        QGLShareContextScope scope(ctx);
+        glDeleteFramebuffers(1, &m_fbo);
+
+        if (m_width || m_height)
+            glDeleteTextures(1, &m_texture);
+    }
+}
+
+void QGLTextureGlyphCache::createTextureData(int width, int height)
+{
+    glGenTextures(1, &m_texture);
+    glBindTexture(GL_TEXTURE_2D, m_texture);
+
+    m_width = width;
+    m_height = height;
+
+    QVarLengthArray<uchar> data(width * height);
+    for (int i = 0; i < data.size(); ++i)
+        data[i] = 0;
+
+    if (m_type == QFontEngineGlyphCache::Raster_RGBMask)
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_ALPHA, GL_UNSIGNED_BYTE, &data[0]);
+    else
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, width, height, 0, GL_ALPHA, GL_UNSIGNED_BYTE, &data[0]);
+
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+}
+
+void QGLTextureGlyphCache::resizeTextureData(int width, int height)
+{
+    // ### the QTextureGlyphCache API needs to be reworked to allow
+    // ### resizeTextureData to fail
+
+    int oldWidth = m_width;
+    int oldHeight = m_height;
+
+    GLuint oldTexture = m_texture;
+    createTextureData(width, height);
+
+    glBindFramebuffer(GL_FRAMEBUFFER_EXT, m_fbo);
+
+    GLuint tmp_texture;
+    glGenTextures(1, &tmp_texture);
+    glBindTexture(GL_TEXTURE_2D, tmp_texture);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, oldWidth, oldHeight, 0,
+                 GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glBindTexture(GL_TEXTURE_2D, 0);
+    glFramebufferTexture2D(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                           GL_TEXTURE_2D, tmp_texture, 0);
+
+    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    glBindTexture(GL_TEXTURE_2D, oldTexture);
+
+    pex->transferMode(BrushDrawingMode);
+
+#ifndef QT_OPENGL_ES_2
+    if (pex->inRenderText)
+        glPushAttrib(GL_ENABLE_BIT | GL_VIEWPORT_BIT | GL_SCISSOR_BIT);
+#endif
+
+    glDisable(GL_STENCIL_TEST);
+    glDisable(GL_DEPTH_TEST);
+    glDisable(GL_SCISSOR_TEST);
+    glDisable(GL_BLEND);
+
+    glViewport(0, 0, oldWidth, oldHeight);
+
+    float vertexCoordinateArray[] = { -1, -1, 1, -1, 1, 1, -1, 1 };
+    float textureCoordinateArray[] = { 0, 0, 1, 0, 1, 1, 0, 1 };
+
+    glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+    glEnableVertexAttribArray(QT_TEXTURE_COORDS_ATTR);
+
+    glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, vertexCoordinateArray);
+    glVertexAttribPointer(QT_TEXTURE_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, textureCoordinateArray);
+
+    pex->shaderManager->blitProgram()->enable();
+    pex->shaderManager->blitProgram()->setUniformValue("imageTexture", QT_IMAGE_TEXTURE_UNIT);
+    pex->shaderManager->setDirty();
+
+    glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+
+    glDisableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+    glDisableVertexAttribArray(QT_TEXTURE_COORDS_ATTR);
+
+    glBindTexture(GL_TEXTURE_2D, m_texture);
+
+#ifdef QT_OPENGL_ES_2
+    QDataBuffer<uchar> buffer(4*oldWidth*oldHeight);
+    buffer.resize(4*oldWidth*oldHeight);
+    glReadPixels(0, 0, oldWidth, oldHeight, GL_RGBA, GL_UNSIGNED_BYTE, buffer.data());
+
+    // do an in-place conversion from GL_RGBA to GL_ALPHA
+    for (int i=0; i<oldWidth*oldHeight; ++i)
+        buffer.data()[i] = buffer.at(4*i + 3);
+
+    glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, oldWidth, oldHeight,
+                    GL_ALPHA, GL_UNSIGNED_BYTE, buffer.data());
+#else
+    glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, oldWidth, oldHeight);
+#endif
+
+    glFramebufferRenderbuffer(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                              GL_RENDERBUFFER_EXT, 0);
+    glDeleteTextures(1, &tmp_texture);
+    glDeleteTextures(1, &oldTexture);
+
+    glBindFramebuffer(GL_FRAMEBUFFER_EXT, ctx->d_ptr->current_fbo);
+
+    glViewport(0, 0, pex->width, pex->height);
+    pex->updateClipScissorTest();
+
+#ifndef QT_OPENGL_ES_2
+    if (pex->inRenderText)
+        glPopAttrib();
+#endif
+}
+
+void QGLTextureGlyphCache::fillTexture(const Coord &c, glyph_t glyph)
+{
+    QImage mask = textureMapForGlyph(glyph);
+    const int maskWidth = mask.width();
+    const int maskHeight = mask.height();
+
+    if (mask.format() == QImage::Format_Mono) {
+        mask = mask.convertToFormat(QImage::Format_Indexed8);
+        for (int y = 0; y < maskHeight; ++y) {
+            uchar *src = (uchar *) mask.scanLine(y);
+            for (int x = 0; x < maskWidth; ++x)
+                src[x] = -src[x]; // convert 0 and 1 into 0 and 255
+        }
+     }
+
+
+    glBindTexture(GL_TEXTURE_2D, m_texture);
+    if (mask.format() == QImage::Format_RGB32) {
+        glTexSubImage2D(GL_TEXTURE_2D, 0, c.x, c.y, maskWidth, maskHeight, GL_BGRA, GL_UNSIGNED_BYTE, mask.bits());
+    } else {
+#ifdef QT_OPENGL_ES2
+        glTexSubImage2D(GL_TEXTURE_2D, 0, c.x, c.y, maskWidth, maskHeight, GL_ALPHA, GL_UNSIGNED_BYTE, mask.bits());
+#else
+        // glTexSubImage2D() might cause some garbage to appear in the texture if the mask width is
+        // not a multiple of four bytes. The bug appeared on a computer with 32-bit Windows Vista
+        // and nVidia GeForce 8500GT. GL_UNPACK_ALIGNMENT is set to four bytes, 'mask' has a
+        // multiple of four bytes per line, and most of the glyph shows up correctly in the
+        // texture, which makes me think that this is a driver bug.
+        // One workaround is to make sure the mask width is a multiple of four bytes, for instance
+        // by converting it to a format with four bytes per pixel. Another is to copy one line at a
+        // time.
+
+        for (int i = 0; i < maskHeight; ++i)
+            glTexSubImage2D(GL_TEXTURE_2D, 0, c.x, c.y + i, maskWidth, 1, GL_ALPHA, GL_UNSIGNED_BYTE, mask.scanLine(i));
+#endif
+    }
+}
+
+int QGLTextureGlyphCache::glyphMargin() const
+{
+#if defined(Q_WS_MAC)
+    return 2;
+#elif defined (Q_WS_X11)
+    return 0;
+#else
+    return m_type == QFontEngineGlyphCache::Raster_RGBMask ? 2 : 0;
+#endif
+}
+
+extern QImage qt_imageForBrush(int brushStyle, bool invert);
+
+////////////////////////////////// Private Methods //////////////////////////////////////////
+
+QGL2PaintEngineExPrivate::~QGL2PaintEngineExPrivate()
+{
+    delete shaderManager;
+}
+
+void QGL2PaintEngineExPrivate::updateTextureFilter(GLenum target, GLenum wrapMode, bool smoothPixmapTransform, GLuint id)
+{
+//    glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT); //### Is it always this texture unit?
+    if (id != GLuint(-1) && id == lastTexture)
+        return;
+
+    lastTexture = id;
+
+    if (smoothPixmapTransform) {
+        glTexParameterf(target, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+        glTexParameterf(target, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    } else {
+        glTexParameterf(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+        glTexParameterf(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    }
+    glTexParameterf(target, GL_TEXTURE_WRAP_S, wrapMode);
+    glTexParameterf(target, GL_TEXTURE_WRAP_T, wrapMode);
+}
+
+
+inline QColor qt_premultiplyColor(QColor c, GLfloat opacity)
+{
+    qreal alpha = c.alphaF() * opacity;
+    c.setAlphaF(alpha);
+    c.setRedF(c.redF() * alpha);
+    c.setGreenF(c.greenF() * alpha);
+    c.setBlueF(c.blueF() * alpha);
+    return c;
+}
+
+
+void QGL2PaintEngineExPrivate::setBrush(const QBrush* brush)
+{
+    currentBrush = brush;
+    brushTextureDirty = true;
+    brushUniformsDirty = true;
+    if (currentBrush->style() == Qt::TexturePattern
+        && qHasPixmapTexture(*brush) && brush->texture().isQBitmap())
+    {
+        shaderManager->setSrcPixelType(QGLEngineShaderManager::TextureSrcWithPattern);
+    } else {
+        shaderManager->setSrcPixelType(currentBrush->style());
+    }
+    shaderManager->optimiseForBrushTransform(currentBrush->transform());
+}
+
+
+void QGL2PaintEngineExPrivate::useSimpleShader()
+{
+    shaderManager->simpleProgram()->enable();
+    shaderManager->setDirty();
+
+    if (matrixDirty)
+        updateMatrix();
+
+    if (simpleShaderMatrixUniformDirty) {
+        shaderManager->simpleProgram()->setUniformValue("pmvMatrix", pmvMatrix);
+        simpleShaderMatrixUniformDirty = false;
+    }
+}
+
+void QGL2PaintEngineExPrivate::updateBrushTexture()
+{
+    Q_Q(QGL2PaintEngineEx);
+//     qDebug("QGL2PaintEngineExPrivate::updateBrushTexture()");
+    Qt::BrushStyle style = currentBrush->style();
+
+    if ( (style >= Qt::Dense1Pattern) && (style <= Qt::DiagCrossPattern) ) {
+        // Get the image data for the pattern
+        QImage texImage = qt_imageForBrush(style, false);
+
+        glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
+        ctx->d_func()->bindTexture(texImage, GL_TEXTURE_2D, GL_RGBA, true, QGLContext::InternalBindOption);
+        updateTextureFilter(GL_TEXTURE_2D, GL_REPEAT, q->state()->renderHints & QPainter::SmoothPixmapTransform);
+    }
+    else if (style >= Qt::LinearGradientPattern && style <= Qt::ConicalGradientPattern) {
+        // Gradiant brush: All the gradiants use the same texture
+
+        const QGradient* g = currentBrush->gradient();
+
+        // We apply global opacity in the fragment shaders, so we always pass 1.0
+        // for opacity to the cache.
+        GLuint texId = QGL2GradientCache::cacheForContext(ctx)->getBuffer(*g, 1.0);
+
+        glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
+        glBindTexture(GL_TEXTURE_2D, texId);
+
+        if (g->spread() == QGradient::RepeatSpread || g->type() == QGradient::ConicalGradient)
+            updateTextureFilter(GL_TEXTURE_2D, GL_REPEAT, q->state()->renderHints & QPainter::SmoothPixmapTransform);
+        else if (g->spread() == QGradient::ReflectSpread)
+            updateTextureFilter(GL_TEXTURE_2D, GL_MIRRORED_REPEAT_IBM, q->state()->renderHints & QPainter::SmoothPixmapTransform);
+        else
+            updateTextureFilter(GL_TEXTURE_2D, GL_CLAMP_TO_EDGE, q->state()->renderHints & QPainter::SmoothPixmapTransform);
+    }
+    else if (style == Qt::TexturePattern) {
+        const QPixmap& texPixmap = currentBrush->texture();
+
+        glActiveTexture(GL_TEXTURE0 + QT_BRUSH_TEXTURE_UNIT);
+        QGLTexture *tex = ctx->d_func()->bindTexture(texPixmap, GL_TEXTURE_2D, GL_RGBA, QGLContext::InternalBindOption);
+        updateTextureFilter(GL_TEXTURE_2D, GL_REPEAT, q->state()->renderHints & QPainter::SmoothPixmapTransform);
+        textureInvertedY = tex->options & QGLContext::InvertedYBindOption ? -1 : 1;
+    }
+    brushTextureDirty = false;
+}
+
+
+void QGL2PaintEngineExPrivate::updateBrushUniforms()
+{
+//     qDebug("QGL2PaintEngineExPrivate::updateBrushUniforms()");
+    Qt::BrushStyle style = currentBrush->style();
+
+    if (style == Qt::NoBrush)
+        return;
+
+    QTransform brushQTransform = currentBrush->transform();
+
+    if (style == Qt::SolidPattern) {
+        QColor col = qt_premultiplyColor(currentBrush->color(), (GLfloat)q->state()->opacity);
+        shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::FragmentColor), col);
+    }
+    else {
+        // All other brushes have a transform and thus need the translation point:
+        QPointF translationPoint;
+
+        if (style <= Qt::DiagCrossPattern) {
+            QColor col = qt_premultiplyColor(currentBrush->color(), (GLfloat)q->state()->opacity);
+
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::PatternColor), col);
+
+            QVector2D halfViewportSize(width*0.5, height*0.5);
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::HalfViewportSize), halfViewportSize);
+        }
+        else if (style == Qt::LinearGradientPattern) {
+            const QLinearGradient *g = static_cast<const QLinearGradient *>(currentBrush->gradient());
+
+            QPointF realStart = g->start();
+            QPointF realFinal = g->finalStop();
+            translationPoint = realStart;
+
+            QPointF l = realFinal - realStart;
+
+            QVector3D linearData(
+                l.x(),
+                l.y(),
+                1.0f / (l.x() * l.x() + l.y() * l.y())
+            );
+
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::LinearData), linearData);
+
+            QVector2D halfViewportSize(width*0.5, height*0.5);
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::HalfViewportSize), halfViewportSize);
+        }
+        else if (style == Qt::ConicalGradientPattern) {
+            const QConicalGradient *g = static_cast<const QConicalGradient *>(currentBrush->gradient());
+            translationPoint   = g->center();
+
+            GLfloat angle = -(g->angle() * 2 * Q_PI) / 360.0;
+
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::Angle), angle);
+
+            QVector2D halfViewportSize(width*0.5, height*0.5);
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::HalfViewportSize), halfViewportSize);
+        }
+        else if (style == Qt::RadialGradientPattern) {
+            const QRadialGradient *g = static_cast<const QRadialGradient *>(currentBrush->gradient());
+            QPointF realCenter = g->center();
+            QPointF realFocal  = g->focalPoint();
+            qreal   realRadius = g->radius();
+            translationPoint   = realFocal;
+
+            QPointF fmp = realCenter - realFocal;
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::Fmp), fmp);
+
+            GLfloat fmp2_m_radius2 = -fmp.x() * fmp.x() - fmp.y() * fmp.y() + realRadius*realRadius;
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::Fmp2MRadius2), fmp2_m_radius2);
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::Inverse2Fmp2MRadius2),
+                                                             GLfloat(1.0 / (2.0*fmp2_m_radius2)));
+
+            QVector2D halfViewportSize(width*0.5, height*0.5);
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::HalfViewportSize), halfViewportSize);
+        }
+        else if (style == Qt::TexturePattern) {
+            const QPixmap& texPixmap = currentBrush->texture();
+
+            if (qHasPixmapTexture(*currentBrush) && currentBrush->texture().isQBitmap()) {
+                QColor col = qt_premultiplyColor(currentBrush->color(), (GLfloat)q->state()->opacity);
+                shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::PatternColor), col);
+            }
+
+            QSizeF invertedTextureSize(1.0 / texPixmap.width(), 1.0 * textureInvertedY / texPixmap.height());
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::InvertedTextureSize), invertedTextureSize);
+
+            QVector2D halfViewportSize(width*0.5, height*0.5);
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::HalfViewportSize), halfViewportSize);
+        }
+        else
+            qWarning("QGL2PaintEngineEx: Unimplemented fill style");
+
+        const QPointF &brushOrigin = q->state()->brushOrigin;
+        QTransform matrix = q->state()->matrix;
+        matrix.translate(brushOrigin.x(), brushOrigin.y());
+
+        QTransform translate(1, 0, 0, 1, -translationPoint.x(), -translationPoint.y());
+        QTransform gl_to_qt(1, 0, 0, -1, 0, height);
+        QTransform inv_matrix = gl_to_qt * (brushQTransform * matrix).inverted() * translate;
+
+        shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::BrushTransform), inv_matrix);
+        shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::BrushTexture), QT_BRUSH_TEXTURE_UNIT);
+    }
+    brushUniformsDirty = false;
+}
+
+
+// This assumes the shader manager has already setup the correct shader program
+void QGL2PaintEngineExPrivate::updateMatrix()
+{
+//     qDebug("QGL2PaintEngineExPrivate::updateMatrix()");
+
+    // We set up the 4x4 transformation matrix on the vertex shaders to
+    // be the equivalent of glOrtho(0, w, h, 0, -1, 1) * transform:
+    //
+    // | 2/width     0     0 -1 |   | m11  m21  0   dx |
+    // |   0    -2/height  0  1 |   | m12  m22  0   dy |
+    // |   0         0    -1  0 | * |  0    0   1   0  |
+    // |   0         0     0  1 |   | m13  m23  0  m33 |
+    //
+    // We expand out the multiplication to save the cost of a full 4x4
+    // matrix multiplication as most of the components are trivial.
+    const QTransform& transform = q->state()->matrix;
+
+    if (mode == TextDrawingMode) {
+        // Text drawing mode is only used for non-scaling transforms
+        pmvMatrix[0][0] = 2.0 / width;
+        pmvMatrix[0][1] = 0.0;
+        pmvMatrix[0][2] = 0.0;
+        pmvMatrix[0][3] = 0.0;
+        pmvMatrix[1][0] = 0.0;
+        pmvMatrix[1][1] = -2.0 / height;
+        pmvMatrix[1][2] = 0.0;
+        pmvMatrix[1][3] = 0.0;
+        pmvMatrix[2][0] = 0.0;
+        pmvMatrix[2][1] = 0.0;
+        pmvMatrix[2][2] = -1.0;
+        pmvMatrix[2][3] = 0.0;
+        pmvMatrix[3][0] = pmvMatrix[0][0] * qRound(transform.dx()) - 1.0;
+        pmvMatrix[3][1] = pmvMatrix[1][1] * qRound(transform.dy()) + 1.0;
+        pmvMatrix[3][2] = 0.0;
+        pmvMatrix[3][3] = 1.0;
+
+        inverseScale = 1;
+    } else {
+        qreal wfactor = 2.0 / width;
+        qreal hfactor = -2.0 / height;
+
+        pmvMatrix[0][0] = wfactor * transform.m11() - transform.m13();
+        pmvMatrix[0][1] = hfactor * transform.m12() + transform.m13();
+        pmvMatrix[0][2] = 0.0;
+        pmvMatrix[0][3] = transform.m13();
+        pmvMatrix[1][0] = wfactor * transform.m21() - transform.m23();
+        pmvMatrix[1][1] = hfactor * transform.m22() + transform.m23();
+        pmvMatrix[1][2] = 0.0;
+        pmvMatrix[1][3] = transform.m23();
+        pmvMatrix[2][0] = 0.0;
+        pmvMatrix[2][1] = 0.0;
+        pmvMatrix[2][2] = -1.0;
+        pmvMatrix[2][3] = 0.0;
+        pmvMatrix[3][0] = wfactor * transform.dx() - transform.m33();
+        pmvMatrix[3][1] = hfactor * transform.dy() + transform.m33();
+        pmvMatrix[3][2] = 0.0;
+        pmvMatrix[3][3] = transform.m33();
+
+        // 1/10000 == 0.0001, so we have good enough res to cover curves
+        // that span the entire widget...
+        inverseScale = qMax(1 / qMax( qMax(qAbs(transform.m11()), qAbs(transform.m22())),
+                    qMax(qAbs(transform.m12()), qAbs(transform.m21())) ),
+                qreal(0.0001));
+    }
+
+    matrixDirty = false;
+
+    // The actual data has been updated so both shader program's uniforms need updating
+    simpleShaderMatrixUniformDirty = true;
+    shaderMatrixUniformDirty = true;
+
+    dasher.setInvScale(inverseScale);
+    stroker.setInvScale(inverseScale);
+}
+
+
+void QGL2PaintEngineExPrivate::updateCompositionMode()
+{
+    // NOTE: The entire paint engine works on pre-multiplied data - which is why some of these
+    //       composition modes look odd.
+//     qDebug() << "QGL2PaintEngineExPrivate::updateCompositionMode() - Setting GL composition mode for " << q->state()->composition_mode;
+    switch(q->state()->composition_mode) {
+    case QPainter::CompositionMode_SourceOver:
+        glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
+        break;
+    case QPainter::CompositionMode_DestinationOver:
+        glBlendFunc(GL_ONE_MINUS_DST_ALPHA, GL_ONE);
+        break;
+    case QPainter::CompositionMode_Clear:
+        glBlendFunc(GL_ZERO, GL_ZERO);
+        break;
+    case QPainter::CompositionMode_Source:
+        glBlendFunc(GL_ONE, GL_ZERO);
+        break;
+    case QPainter::CompositionMode_Destination:
+        glBlendFunc(GL_ZERO, GL_ONE);
+        break;
+    case QPainter::CompositionMode_SourceIn:
+        glBlendFunc(GL_DST_ALPHA, GL_ZERO);
+        break;
+    case QPainter::CompositionMode_DestinationIn:
+        glBlendFunc(GL_ZERO, GL_SRC_ALPHA);
+        break;
+    case QPainter::CompositionMode_SourceOut:
+        glBlendFunc(GL_ONE_MINUS_DST_ALPHA, GL_ZERO);
+        break;
+    case QPainter::CompositionMode_DestinationOut:
+        glBlendFunc(GL_ZERO, GL_ONE_MINUS_SRC_ALPHA);
+        break;
+    case QPainter::CompositionMode_SourceAtop:
+        glBlendFunc(GL_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+        break;
+    case QPainter::CompositionMode_DestinationAtop:
+        glBlendFunc(GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA);
+        break;
+    case QPainter::CompositionMode_Xor:
+        glBlendFunc(GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+        break;
+    case QPainter::CompositionMode_Plus:
+        glBlendFunc(GL_ONE, GL_ONE);
+        break;
+    default:
+        qWarning("Unsupported composition mode");
+        break;
+    }
+
+    compositionModeDirty = false;
+}
+
+static inline void setCoords(GLfloat *coords, const QGLRect &rect)
+{
+    coords[0] = rect.left;
+    coords[1] = rect.top;
+    coords[2] = rect.right;
+    coords[3] = rect.top;
+    coords[4] = rect.right;
+    coords[5] = rect.bottom;
+    coords[6] = rect.left;
+    coords[7] = rect.bottom;
+}
+
+void QGL2PaintEngineExPrivate::drawTexture(const QGLRect& dest, const QGLRect& src, const QSize &textureSize, bool opaque, bool pattern)
+{
+    // Setup for texture drawing
+    shaderManager->setSrcPixelType(pattern ? QGLEngineShaderManager::PatternSrc : QGLEngineShaderManager::ImageSrc);
+    if (prepareForDraw(opaque))
+        shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::ImageTexture), QT_IMAGE_TEXTURE_UNIT);
+
+    if (pattern) {
+        QColor col = qt_premultiplyColor(q->state()->pen.color(), (GLfloat)q->state()->opacity);
+        shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::PatternColor), col);
+    }
+
+    GLfloat dx = 1.0 / textureSize.width();
+    GLfloat dy = 1.0 / textureSize.height();
+
+    QGLRect srcTextureRect(src.left*dx, src.top*dy, src.right*dx, src.bottom*dy);
+
+    setCoords(staticVertexCoordinateArray, dest);
+    setCoords(staticTextureCoordinateArray, srcTextureRect);
+
+    glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+}
+
+void QGL2PaintEngineEx::beginNativePainting()
+{
+    Q_D(QGL2PaintEngineEx);
+    ensureActive();
+    d->transferMode(BrushDrawingMode);
+
+    QGLContext *ctx = d->ctx;
+    glUseProgram(0);
+
+#ifndef QT_OPENGL_ES_2
+    // be nice to people who mix OpenGL 1.x code with QPainter commands
+    // by setting modelview and projection matrices to mirror the GL 1
+    // paint engine
+    const QTransform& mtx = state()->matrix;
+
+    float mv_matrix[4][4] =
+    {
+        { mtx.m11(), mtx.m12(),     0, mtx.m13() },
+        { mtx.m21(), mtx.m22(),     0, mtx.m23() },
+        {         0,         0,     1,         0 },
+        {  mtx.dx(),  mtx.dy(),     0, mtx.m33() }
+    };
+
+    const QSize sz = d->device->size();
+
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+    glOrtho(0, sz.width(), sz.height(), 0, -999999, 999999);
+
+    glMatrixMode(GL_MODELVIEW);
+    glLoadMatrixf(&mv_matrix[0][0]);
+#else
+    Q_UNUSED(ctx);
+#endif
+
+    d->lastTexture = GLuint(-1);
+    d->dirtyStencilRegion = QRect(0, 0, d->width, d->height);
+    d->resetGLState();
+
+    d->shaderManager->setDirty();
+
+    d->needsSync = true;
+}
+
+void QGL2PaintEngineExPrivate::resetGLState()
+{
+    glDisable(GL_BLEND);
+    glActiveTexture(GL_TEXTURE0);
+    glDisable(GL_STENCIL_TEST);
+    glDisable(GL_DEPTH_TEST);
+    glDisable(GL_SCISSOR_TEST);
+    glDepthMask(true);
+    glDepthFunc(GL_LESS);
+    glClearDepth(1);
+}
+
+void QGL2PaintEngineEx::endNativePainting()
+{
+    Q_D(QGL2PaintEngineEx);
+    d->needsSync = true;
+}
+
+const QGLContext *QGL2PaintEngineEx::context()
+{
+    Q_D(QGL2PaintEngineEx);
+    return d->ctx;
+}
+
+void QGL2PaintEngineExPrivate::transferMode(EngineMode newMode)
+{
+    if (newMode == mode)
+        return;
+
+    if (mode == TextDrawingMode || mode == ImageDrawingMode || mode == ImageArrayDrawingMode) {
+        glDisableVertexAttribArray(QT_TEXTURE_COORDS_ATTR);
+        glDisableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+        glDisableVertexAttribArray(QT_OPACITY_ATTR);
+
+        lastTexture = GLuint(-1);
+    }
+
+    if (mode == TextDrawingMode)
+        matrixDirty = true;
+
+    if (newMode == TextDrawingMode) {
+        glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+        glEnableVertexAttribArray(QT_TEXTURE_COORDS_ATTR);
+
+        glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, vertexCoordinateArray.data());
+        glVertexAttribPointer(QT_TEXTURE_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, textureCoordinateArray.data());
+
+        matrixDirty = true;
+    }
+
+    if (newMode == ImageDrawingMode) {
+        glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+        glEnableVertexAttribArray(QT_TEXTURE_COORDS_ATTR);
+
+        glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, staticVertexCoordinateArray);
+        glVertexAttribPointer(QT_TEXTURE_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, staticTextureCoordinateArray);
+    }
+
+    if (newMode == ImageArrayDrawingMode) {
+        glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+        glEnableVertexAttribArray(QT_TEXTURE_COORDS_ATTR);
+        glEnableVertexAttribArray(QT_OPACITY_ATTR);
+
+        glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, vertexCoordinateArray.data());
+        glVertexAttribPointer(QT_TEXTURE_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, textureCoordinateArray.data());
+        glVertexAttribPointer(QT_OPACITY_ATTR, 1, GL_FLOAT, GL_FALSE, 0, opacityArray.data());
+    }
+
+    // This needs to change when we implement high-quality anti-aliasing...
+    if (newMode != TextDrawingMode)
+        shaderManager->setMaskType(QGLEngineShaderManager::NoMask);
+
+    mode = newMode;
+}
+
+// Assumes everything is configured for the brush you want to use
+void QGL2PaintEngineExPrivate::fill(const QVectorPath& path)
+{
+    transferMode(BrushDrawingMode);
+
+    // Might need to call updateMatrix to re-calculate inverseScale
+    if (matrixDirty)
+        updateMatrix();
+
+    const QPointF* const points = reinterpret_cast<const QPointF*>(path.points());
+
+    // Check to see if there's any hints
+    if (path.shape() == QVectorPath::RectangleHint) {
+        QGLRect rect(points[0].x(), points[0].y(), points[2].x(), points[2].y());
+        prepareForDraw(currentBrush->isOpaque());
+        composite(rect);
+    } else if (path.shape() == QVectorPath::EllipseHint
+             || path.shape() == QVectorPath::ConvexPolygonHint)
+    {
+        vertexCoordinateArray.clear();
+        vertexCoordinateArray.addPath(path, inverseScale, false);
+        prepareForDraw(currentBrush->isOpaque());
+        drawVertexArrays(vertexCoordinateArray, GL_TRIANGLE_FAN);
+    } else {
+        // The path is too complicated & needs the stencil technique
+        vertexCoordinateArray.clear();
+        vertexCoordinateArray.addPath(path, inverseScale, false);
+
+        fillStencilWithVertexArray(vertexCoordinateArray, path.hasWindingFill());
+
+        glStencilMask(0xff);
+        glStencilOp(GL_KEEP, GL_REPLACE, GL_REPLACE);
+
+        if (q->state()->clipTestEnabled) {
+            // Pass when high bit is set, replace stencil value with current clip
+            glStencilFunc(GL_NOTEQUAL, q->state()->currentClip, GL_STENCIL_HIGH_BIT);
+        } else if (path.hasWindingFill()) {
+            // Pass when any bit is set, replace stencil value with 0
+            glStencilFunc(GL_NOTEQUAL, 0, 0xff);
+        } else {
+            // Pass when high bit is set, replace stencil value with 0
+            glStencilFunc(GL_NOTEQUAL, 0, GL_STENCIL_HIGH_BIT);
+        }
+
+        prepareForDraw(currentBrush->isOpaque());
+
+        if (inRenderText)
+            prepareDepthRangeForRenderText();
+
+        // Stencil the brush onto the dest buffer
+        composite(vertexCoordinateArray.boundingRect());
+
+        if (inRenderText)
+            restoreDepthRangeForRenderText();
+
+        glStencilMask(0);
+
+        updateClipScissorTest();
+    }
+}
+
+
+void QGL2PaintEngineExPrivate::fillStencilWithVertexArray(const float *data,
+                                                          int count,
+                                                          const QVector<int> *stops,
+                                                          const QGLRect &bounds,
+                                                          StencilFillMode mode)
+{
+    Q_ASSERT(count || stops);
+
+//     qDebug("QGL2PaintEngineExPrivate::fillStencilWithVertexArray()");
+    glStencilMask(0xff); // Enable stencil writes
+
+    if (dirtyStencilRegion.intersects(currentScissorBounds)) {
+        QVector<QRect> clearRegion = dirtyStencilRegion.intersected(currentScissorBounds).rects();
+        glClearStencil(0); // Clear to zero
+        for (int i = 0; i < clearRegion.size(); ++i) {
+#ifndef QT_GL_NO_SCISSOR_TEST
+            setScissor(clearRegion.at(i));
+#endif
+            glClear(GL_STENCIL_BUFFER_BIT);
+        }
+
+        dirtyStencilRegion -= currentScissorBounds;
+
+#ifndef QT_GL_NO_SCISSOR_TEST
+        updateClipScissorTest();
+#endif
+    }
+
+    glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE); // Disable color writes
+    useSimpleShader();
+    glEnable(GL_STENCIL_TEST); // For some reason, this has to happen _after_ the simple shader is use()'d
+
+#ifndef QT_OPENGL_ES_2
+    if (inRenderText) {
+        glPushAttrib(GL_ENABLE_BIT);
+        glDisable(GL_DEPTH_TEST);
+    }
+#endif
+
+    if (mode == WindingFillMode) {
+        Q_ASSERT(stops && !count);
+        if (q->state()->clipTestEnabled) {
+            // Flatten clip values higher than current clip, and set high bit to match current clip
+            glStencilFunc(GL_LEQUAL, GL_STENCIL_HIGH_BIT | q->state()->currentClip, ~GL_STENCIL_HIGH_BIT);
+            glStencilOp(GL_KEEP, GL_REPLACE, GL_REPLACE);
+            composite(bounds);
+
+            glStencilFunc(GL_EQUAL, GL_STENCIL_HIGH_BIT, GL_STENCIL_HIGH_BIT);
+        } else if (!stencilClean) {
+            // Clear stencil buffer within bounding rect
+            glStencilFunc(GL_ALWAYS, 0, 0xff);
+            glStencilOp(GL_ZERO, GL_ZERO, GL_ZERO);
+            composite(bounds);
+        }
+
+        // Inc. for front-facing triangle
+        glStencilOpSeparate(GL_FRONT, GL_KEEP, GL_INCR_WRAP, GL_INCR_WRAP);
+        // Dec. for back-facing "holes"
+        glStencilOpSeparate(GL_BACK, GL_KEEP, GL_DECR_WRAP, GL_DECR_WRAP);
+        glStencilMask(~GL_STENCIL_HIGH_BIT);
+        drawVertexArrays(data, stops, GL_TRIANGLE_FAN);
+
+        if (q->state()->clipTestEnabled) {
+            // Clear high bit of stencil outside of path
+            glStencilFunc(GL_EQUAL, q->state()->currentClip, ~GL_STENCIL_HIGH_BIT);
+            glStencilOp(GL_KEEP, GL_REPLACE, GL_REPLACE);
+            glStencilMask(GL_STENCIL_HIGH_BIT);
+            composite(bounds);
+        }
+    } else if (mode == OddEvenFillMode) {
+        glStencilMask(GL_STENCIL_HIGH_BIT);
+        glStencilOp(GL_KEEP, GL_KEEP, GL_INVERT); // Simply invert the stencil bit
+        drawVertexArrays(data, stops, GL_TRIANGLE_FAN);
+
+    } else { // TriStripStrokeFillMode
+        Q_ASSERT(count && !stops); // tristrips generated directly, so no vertexArray or stops
+        glStencilMask(GL_STENCIL_HIGH_BIT);
+#if 0
+        glStencilOp(GL_KEEP, GL_KEEP, GL_INVERT); // Simply invert the stencil bit
+        glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+        glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, data);
+        glDrawArrays(GL_TRIANGLE_STRIP, 0, count);
+        glDisableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+#else
+
+        glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);
+        if (q->state()->clipTestEnabled) {
+            glStencilFunc(GL_LEQUAL, q->state()->currentClip | GL_STENCIL_HIGH_BIT,
+                          ~GL_STENCIL_HIGH_BIT);
+        } else {
+            glStencilFunc(GL_ALWAYS, GL_STENCIL_HIGH_BIT, 0xff);
+        }
+        glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+        glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, data);
+        glDrawArrays(GL_TRIANGLE_STRIP, 0, count);
+        glDisableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+#endif
+    }
+
+    // Enable color writes & disable stencil writes
+    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+
+#ifndef QT_OPENGL_ES_2
+    if (inRenderText)
+        glPopAttrib();
+#endif
+
+}
+
+/*
+    If the maximum value in the stencil buffer is GL_STENCIL_HIGH_BIT - 1,
+    restore the stencil buffer to a pristine state.  The current clip region
+    is set to 1, and the rest to 0.
+*/
+void QGL2PaintEngineExPrivate::resetClipIfNeeded()
+{
+    if (maxClip != (GL_STENCIL_HIGH_BIT - 1))
+        return;
+
+    Q_Q(QGL2PaintEngineEx);
+
+    useSimpleShader();
+    glEnable(GL_STENCIL_TEST);
+    glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
+
+    QRectF bounds = q->state()->matrix.inverted().mapRect(QRectF(0, 0, width, height));
+    QGLRect rect(bounds.left(), bounds.top(), bounds.right(), bounds.bottom());
+
+    // Set high bit on clip region
+    glStencilFunc(GL_LEQUAL, q->state()->currentClip, 0xff);
+    glStencilOp(GL_KEEP, GL_INVERT, GL_INVERT);
+    glStencilMask(GL_STENCIL_HIGH_BIT);
+    composite(rect);
+
+    // Reset clipping to 1 and everything else to zero
+    glStencilFunc(GL_NOTEQUAL, 0x01, GL_STENCIL_HIGH_BIT);
+    glStencilOp(GL_ZERO, GL_REPLACE, GL_REPLACE);
+    glStencilMask(0xff);
+    composite(rect);
+
+    q->state()->currentClip = 1;
+    q->state()->canRestoreClip = false;
+
+    maxClip = 1;
+
+    glStencilMask(0x0);
+    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+}
+
+bool QGL2PaintEngineExPrivate::prepareForDraw(bool srcPixelsAreOpaque)
+{
+    if (brushTextureDirty && mode != ImageDrawingMode && mode != ImageArrayDrawingMode)
+        updateBrushTexture();
+
+    if (compositionModeDirty)
+        updateCompositionMode();
+
+    if (matrixDirty)
+        updateMatrix();
+
+    const bool stateHasOpacity = q->state()->opacity < 0.99f;
+    if (q->state()->composition_mode == QPainter::CompositionMode_Source
+        || (q->state()->composition_mode == QPainter::CompositionMode_SourceOver
+            && srcPixelsAreOpaque && !stateHasOpacity))
+    {
+        glDisable(GL_BLEND);
+    } else {
+        glEnable(GL_BLEND);
+    }
+
+    QGLEngineShaderManager::OpacityMode opacityMode;
+    if (mode == ImageArrayDrawingMode) {
+        opacityMode = QGLEngineShaderManager::AttributeOpacity;
+    } else {
+        opacityMode = stateHasOpacity ? QGLEngineShaderManager::UniformOpacity
+                                      : QGLEngineShaderManager::NoOpacity;
+        if (stateHasOpacity && (mode != ImageDrawingMode)) {
+            // Using a brush
+            bool brushIsPattern = (currentBrush->style() >= Qt::Dense1Pattern) &&
+                                  (currentBrush->style() <= Qt::DiagCrossPattern);
+
+            if ((currentBrush->style() == Qt::SolidPattern) || brushIsPattern)
+                opacityMode = QGLEngineShaderManager::NoOpacity; // Global opacity handled by srcPixel shader
+        }
+    }
+    shaderManager->setOpacityMode(opacityMode);
+
+    bool changed = shaderManager->useCorrectShaderProg();
+    // If the shader program needs changing, we change it and mark all uniforms as dirty
+    if (changed) {
+        // The shader program has changed so mark all uniforms as dirty:
+        brushUniformsDirty = true;
+        shaderMatrixUniformDirty = true;
+        opacityUniformDirty = true;
+    }
+
+    if (brushUniformsDirty && mode != ImageDrawingMode && mode != ImageArrayDrawingMode)
+        updateBrushUniforms();
+
+    if (shaderMatrixUniformDirty) {
+        shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::PmvMatrix), pmvMatrix);
+        shaderMatrixUniformDirty = false;
+    }
+
+    if (opacityMode == QGLEngineShaderManager::UniformOpacity && opacityUniformDirty) {
+        shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::GlobalOpacity), (GLfloat)q->state()->opacity);
+        opacityUniformDirty = false;
+    }
+
+    return changed;
+}
+
+void QGL2PaintEngineExPrivate::composite(const QGLRect& boundingRect)
+{
+    // Setup a vertex array for the bounding rect:
+    GLfloat rectVerts[] = {
+        boundingRect.left, boundingRect.top,
+        boundingRect.left, boundingRect.bottom,
+        boundingRect.right, boundingRect.bottom,
+        boundingRect.right, boundingRect.top
+    };
+
+    glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+    glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, rectVerts);
+
+    glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+
+    glDisableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+}
+
+// Draws the vertex array as a set of <vertexArrayStops.size()> triangle fans.
+void QGL2PaintEngineExPrivate::drawVertexArrays(const float *data, const QVector<int> *stops,
+                                                GLenum primitive)
+{
+    // Now setup the pointer to the vertex array:
+    glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+    glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, data);
+
+    int previousStop = 0;
+    foreach(int stop, *stops) {
+/*
+        qDebug("Drawing triangle fan for vertecies %d -> %d:", previousStop, stop-1);
+        for (int i=previousStop; i<stop; ++i)
+            qDebug("   %02d: [%.2f, %.2f]", i, vertexArray.data()[i].x, vertexArray.data()[i].y);
+*/
+        glDrawArrays(primitive, previousStop, stop - previousStop);
+        previousStop = stop;
+    }
+    glDisableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+}
+
+void QGL2PaintEngineExPrivate::prepareDepthRangeForRenderText()
+{
+#ifndef QT_OPENGL_ES_2
+    // Get the z translation value from the model view matrix and
+    // transform it using the ortogonal projection with z-near = 0,
+    // and z-far = 1, which is used in QGLWidget::renderText()
+    GLdouble model[4][4];
+    glGetDoublev(GL_MODELVIEW_MATRIX, &model[0][0]);
+    float deviceZ = -2 * model[3][2] - 1;
+
+    glGetFloatv(GL_DEPTH_RANGE, depthRange);
+    float windowZ = depthRange[0] + (deviceZ + 1) * 0.5 * (depthRange[1] - depthRange[0]);
+
+    glDepthRange(windowZ, windowZ);
+#endif
+}
+
+void QGL2PaintEngineExPrivate::restoreDepthRangeForRenderText()
+{
+#ifndef QT_OPENGL_ES_2
+    glDepthRange(depthRange[0], depthRange[1]);
+#endif
+}
+
+/////////////////////////////////// Public Methods //////////////////////////////////////////
+
+QGL2PaintEngineEx::QGL2PaintEngineEx()
+    : QPaintEngineEx(*(new QGL2PaintEngineExPrivate(this)))
+{
+}
+
+QGL2PaintEngineEx::~QGL2PaintEngineEx()
+{
+}
+
+void QGL2PaintEngineEx::fill(const QVectorPath &path, const QBrush &brush)
+{
+    Q_D(QGL2PaintEngineEx);
+
+    Qt::BrushStyle style = qbrush_style(brush);
+    if (style == Qt::NoBrush)
+        return;
+    if (!d->inRenderText)
+        ensureActive();
+
+    QOpenGL2PaintEngineState *s = state();
+    bool doOffset = !(s->renderHints & QPainter::Antialiasing) && style == Qt::SolidPattern;
+
+    if (doOffset) {
+        d->temporaryTransform = s->matrix;
+        QTransform tx = QTransform::fromTranslate(.49, .49);
+        s->matrix = s->matrix * tx;
+        d->matrixDirty = true;
+    }
+
+    d->setBrush(&brush);
+    d->fill(path);
+
+    if (doOffset) {
+        s->matrix = d->temporaryTransform;
+        d->matrixDirty = true;
+    }
+}
+
+void QGL2PaintEngineEx::stroke(const QVectorPath &path, const QPen &pen)
+{
+    Q_D(QGL2PaintEngineEx);
+
+    Qt::PenStyle penStyle = qpen_style(pen);
+    const QBrush &penBrush = qpen_brush(pen);
+    if (penStyle == Qt::NoPen || qbrush_style(penBrush) == Qt::NoBrush)
+        return;
+
+    QOpenGL2PaintEngineState *s = state();
+
+    ensureActive();
+
+    bool doOffset = !(s->renderHints & QPainter::Antialiasing);
+    if (doOffset) {
+        d->temporaryTransform = s->matrix;
+        QTransform tx = QTransform::fromTranslate(0.49, .49);
+        s->matrix = s->matrix * tx;
+        d->matrixDirty = true;
+    }
+
+    bool opaque = penBrush.isOpaque() && s->opacity > 0.99;
+    d->setBrush(&penBrush);
+    d->transferMode(BrushDrawingMode);
+
+    // updateMatrix() is responsible for setting the inverse scale on
+    // the strokers, so we need to call it here and not wait for
+    // prepareForDraw() down below.
+    d->updateMatrix();
+
+    if (penStyle == Qt::SolidLine) {
+        d->stroker.process(path, pen);
+
+    } else { // Some sort of dash
+        d->dasher.process(path, pen);
+
+        QVectorPath dashStroke(d->dasher.points(),
+                               d->dasher.elementCount(),
+                               d->dasher.elementTypes());
+        d->stroker.process(dashStroke, pen);
+    }
+
+
+    QGLContext *ctx = d->ctx;
+
+    if (opaque) {
+        d->prepareForDraw(opaque);
+        glEnableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+        glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, false, 0, d->stroker.vertices());
+        glDrawArrays(GL_TRIANGLE_STRIP, 0, d->stroker.vertexCount() / 2);
+
+//         QBrush b(Qt::green);
+//         d->setBrush(&b);
+//         d->prepareForDraw(true);
+//         glDrawArrays(GL_LINE_STRIP, 0, d->stroker.vertexCount() / 2);
+
+        glDisableVertexAttribArray(QT_VERTEX_COORDS_ATTR);
+
+    } else {
+        qreal width = qpen_widthf(pen) / 2;
+        if (width == 0)
+            width = 0.5;
+        qreal extra = pen.joinStyle() == Qt::MiterJoin
+                      ? qMax(pen.miterLimit() * width, width)
+                      : width;
+
+        if (pen.isCosmetic())
+            extra = extra * d->inverseScale;
+
+        QRectF bounds = path.controlPointRect().adjusted(-extra, -extra, extra, extra);
+
+        d->fillStencilWithVertexArray(d->stroker.vertices(), d->stroker.vertexCount() / 2,
+                                      0, bounds, QGL2PaintEngineExPrivate::TriStripStrokeFillMode);
+
+        glStencilOp(GL_KEEP, GL_REPLACE, GL_REPLACE);
+
+        // Pass when any bit is set, replace stencil value with 0
+        glStencilFunc(GL_NOTEQUAL, 0, GL_STENCIL_HIGH_BIT);
+        d->prepareForDraw(false);
+
+        // Stencil the brush onto the dest buffer
+        d->composite(bounds);
+
+        glStencilMask(0);
+
+        d->updateClipScissorTest();
+    }
+
+    if (doOffset) {
+        s->matrix = d->temporaryTransform;
+        d->matrixDirty = true;
+    }
+}
+
+void QGL2PaintEngineEx::penChanged() { }
+void QGL2PaintEngineEx::brushChanged() { }
+void QGL2PaintEngineEx::brushOriginChanged() { }
+
+void QGL2PaintEngineEx::opacityChanged()
+{
+//    qDebug("QGL2PaintEngineEx::opacityChanged()");
+    Q_D(QGL2PaintEngineEx);
+    state()->opacityChanged = true;
+
+    Q_ASSERT(d->shaderManager);
+    d->brushUniformsDirty = true;
+    d->opacityUniformDirty = true;
+}
+
+void QGL2PaintEngineEx::compositionModeChanged()
+{
+//     qDebug("QGL2PaintEngineEx::compositionModeChanged()");
+    Q_D(QGL2PaintEngineEx);
+    state()->compositionModeChanged = true;
+    d->compositionModeDirty = true;
+}
+
+void QGL2PaintEngineEx::renderHintsChanged()
+{
+    state()->renderHintsChanged = true;
+
+#if !defined(QT_OPENGL_ES_2)
+    if ((state()->renderHints & QPainter::Antialiasing)
+        || (state()->renderHints & QPainter::HighQualityAntialiasing))
+        glEnable(GL_MULTISAMPLE);
+    else
+        glDisable(GL_MULTISAMPLE);
+#endif
+
+    Q_D(QGL2PaintEngineEx);
+    d->lastTexture = GLuint(-1);
+    d->brushTextureDirty = true;
+//    qDebug("QGL2PaintEngineEx::renderHintsChanged() not implemented!");
+}
+
+void QGL2PaintEngineEx::transformChanged()
+{
+    Q_D(QGL2PaintEngineEx);
+    d->matrixDirty = true;
+    state()->matrixChanged = true;
+}
+
+
+void QGL2PaintEngineEx::drawPixmap(const QRectF& dest, const QPixmap & pixmap, const QRectF & src)
+{
+    Q_D(QGL2PaintEngineEx);
+    ensureActive();
+    d->transferMode(ImageDrawingMode);
+
+    QGLContext *ctx = d->ctx;
+    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    QGLTexture *texture =
+        ctx->d_func()->bindTexture(pixmap, GL_TEXTURE_2D, GL_RGBA,
+                                   QGLContext::InternalBindOption
+                                   | QGLContext::CanFlipNativePixmapBindOption);
+
+    GLfloat top = texture->options & QGLContext::InvertedYBindOption ? (pixmap.height() - src.top()) : src.top();
+    GLfloat bottom = texture->options & QGLContext::InvertedYBindOption ? (pixmap.height() - src.bottom()) : src.bottom();
+    QGLRect srcRect(src.left(), top, src.right(), bottom);
+
+    bool isBitmap = pixmap.isQBitmap();
+    bool isOpaque = !isBitmap && !pixmap.hasAlphaChannel();
+
+    d->updateTextureFilter(GL_TEXTURE_2D, GL_CLAMP_TO_EDGE,
+                           state()->renderHints & QPainter::SmoothPixmapTransform, texture->id);
+    d->drawTexture(dest, srcRect, pixmap.size(), isOpaque, isBitmap);
+}
+
+void QGL2PaintEngineEx::drawImage(const QRectF& dest, const QImage& image, const QRectF& src,
+                        Qt::ImageConversionFlags)
+{
+    Q_D(QGL2PaintEngineEx);
+    ensureActive();
+    d->transferMode(ImageDrawingMode);
+
+    QGLContext *ctx = d->ctx;
+    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    QGLTexture *texture = ctx->d_func()->bindTexture(image, GL_TEXTURE_2D, GL_RGBA, QGLContext::InternalBindOption);
+    GLuint id = texture->id;
+
+    d->updateTextureFilter(GL_TEXTURE_2D, GL_CLAMP_TO_EDGE,
+                           state()->renderHints & QPainter::SmoothPixmapTransform, id);
+    d->drawTexture(dest, src, image.size(), !image.hasAlphaChannel());
+}
+
+void QGL2PaintEngineEx::drawTexture(const QRectF &dest, GLuint textureId, const QSize &size, const QRectF &src)
+{
+    Q_D(QGL2PaintEngineEx);
+    ensureActive();
+    d->transferMode(ImageDrawingMode);
+
+#ifndef QT_OPENGL_ES_2
+    QGLContext *ctx = d->ctx;
+#endif
+    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    glBindTexture(GL_TEXTURE_2D, textureId);
+
+    QGLRect srcRect(src.left(), src.bottom(), src.right(), src.top());
+
+    d->updateTextureFilter(GL_TEXTURE_2D, GL_CLAMP_TO_EDGE,
+                           state()->renderHints & QPainter::SmoothPixmapTransform, textureId);
+    d->drawTexture(dest, srcRect, size, false);
+}
+
+void QGL2PaintEngineEx::drawTextItem(const QPointF &p, const QTextItem &textItem)
+{
+    Q_D(QGL2PaintEngineEx);
+
+    if (!d->inRenderText)
+        ensureActive();
+    QOpenGL2PaintEngineState *s = state();
+
+    const QTextItemInt &ti = static_cast<const QTextItemInt &>(textItem);
+
+    bool drawCached = true;
+
+    if (s->matrix.type() > QTransform::TxTranslate)
+        drawCached = false;
+
+    // don't try to cache huge fonts
+    if (ti.fontEngine->fontDef.pixelSize * qSqrt(s->matrix.determinant()) >= 64)
+        drawCached = false;
+
+    QFontEngineGlyphCache::Type glyphType = ti.fontEngine->glyphFormat >= 0
+                                            ? QFontEngineGlyphCache::Type(ti.fontEngine->glyphFormat)
+                                            : d->glyphCacheType;
+
+    if (d->inRenderText)
+        glyphType = QFontEngineGlyphCache::Raster_A8;
+
+    if (glyphType == QFontEngineGlyphCache::Raster_RGBMask
+        && state()->composition_mode != QPainter::CompositionMode_Source
+        && state()->composition_mode != QPainter::CompositionMode_SourceOver)
+    {
+        drawCached = false;
+    }
+
+    if (drawCached) {
+        d->drawCachedGlyphs(p, glyphType, ti);
+        return;
+    }
+
+    QPaintEngineEx::drawTextItem(p, ti);
+}
+
+void QGL2PaintEngineExPrivate::drawCachedGlyphs(const QPointF &p, QFontEngineGlyphCache::Type glyphType,
+                                                const QTextItemInt &ti)
+{
+    Q_Q(QGL2PaintEngineEx);
+    QOpenGL2PaintEngineState *s = q->state();
+
+    QVarLengthArray<QFixedPoint> positions;
+    QVarLengthArray<glyph_t> glyphs;
+    QTransform matrix = QTransform::fromTranslate(p.x(), p.y());
+    ti.fontEngine->getGlyphPositions(ti.glyphs, matrix, ti.flags, glyphs, positions);
+
+    QGLTextureGlyphCache *cache =
+        (QGLTextureGlyphCache *) ti.fontEngine->glyphCache(ctx, s->matrix);
+
+    if (!cache || cache->cacheType() != glyphType) {
+        cache = new QGLTextureGlyphCache(ctx, glyphType, s->matrix);
+        ti.fontEngine->setGlyphCache(ctx, cache);
+    }
+
+    cache->setPaintEnginePrivate(this);
+    cache->populate(ti, glyphs, positions);
+
+    if (cache->width() == 0 || cache->height() == 0)
+        return;
+
+    if (inRenderText)
+        transferMode(BrushDrawingMode);
+    transferMode(TextDrawingMode);
+
+    int margin = cache->glyphMargin();
+
+    GLfloat dx = 1.0 / cache->width();
+    GLfloat dy = 1.0 / cache->height();
+
+    QGLPoint *oldVertexCoordinateDataPtr = vertexCoordinateArray.data();
+    QGLPoint *oldTextureCoordinateDataPtr = textureCoordinateArray.data();
+
+    vertexCoordinateArray.clear();
+    textureCoordinateArray.clear();
+
+    for (int i=0; i<glyphs.size(); ++i) {
+        const QTextureGlyphCache::Coord &c = cache->coords.value(glyphs[i]);
+        int x = positions[i].x.toInt() + c.baseLineX - margin;
+        int y = positions[i].y.toInt() - c.baseLineY - margin;
+
+        vertexCoordinateArray.addRect(QRectF(x, y, c.w, c.h));
+        textureCoordinateArray.addRect(QRectF(c.x*dx, c.y*dy, c.w * dx, c.h * dy));
+    }
+
+    if (vertexCoordinateArray.data() != oldVertexCoordinateDataPtr)
+        glVertexAttribPointer(QT_VERTEX_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, vertexCoordinateArray.data());
+    if (textureCoordinateArray.data() != oldTextureCoordinateDataPtr)
+        glVertexAttribPointer(QT_TEXTURE_COORDS_ATTR, 2, GL_FLOAT, GL_FALSE, 0, textureCoordinateArray.data());
+
+    QBrush pensBrush = q->state()->pen.brush();
+    setBrush(&pensBrush);
+
+    if (inRenderText)
+        prepareDepthRangeForRenderText();
+
+    if (glyphType == QFontEngineGlyphCache::Raster_RGBMask) {
+
+        // Subpixel antialiasing without gamma correction
+
+        QPainter::CompositionMode compMode = q->state()->composition_mode;
+        Q_ASSERT(compMode == QPainter::CompositionMode_Source
+            || compMode == QPainter::CompositionMode_SourceOver);
+
+        shaderManager->setMaskType(QGLEngineShaderManager::SubPixelMaskPass1);
+
+        if (pensBrush.style() == Qt::SolidPattern) {
+            // Solid patterns can get away with only one pass.
+            QColor c = pensBrush.color();
+            qreal oldOpacity = q->state()->opacity;
+            if (compMode == QPainter::CompositionMode_Source) {
+                c = qt_premultiplyColor(c, q->state()->opacity);
+                q->state()->opacity = 1;
+                opacityUniformDirty = true;
+            }
+
+            compositionModeDirty = false; // I can handle this myself, thank you very much
+            prepareForDraw(false); // Text always causes src pixels to be transparent
+
+            // prepareForDraw() have set the opacity on the current shader, so the opacity state can now be reset.
+            if (compMode == QPainter::CompositionMode_Source) {
+                q->state()->opacity = oldOpacity;
+                opacityUniformDirty = true;
+            }
+
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_CONSTANT_COLOR, GL_ONE_MINUS_SRC_COLOR);
+            glBlendColor(c.redF(), c.greenF(), c.blueF(), c.alphaF());
+        } else {
+            // Other brush styles need two passes.
+
+            qreal oldOpacity = q->state()->opacity;
+            if (compMode == QPainter::CompositionMode_Source) {
+                q->state()->opacity = 1;
+                opacityUniformDirty = true;
+                pensBrush = Qt::white;
+                setBrush(&pensBrush);
+            }
+
+            compositionModeDirty = false; // I can handle this myself, thank you very much
+            prepareForDraw(false); // Text always causes src pixels to be transparent
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_ZERO, GL_ONE_MINUS_SRC_COLOR);
+
+            glActiveTexture(GL_TEXTURE0 + QT_MASK_TEXTURE_UNIT);
+            glBindTexture(GL_TEXTURE_2D, cache->texture());
+            updateTextureFilter(GL_TEXTURE_2D, GL_REPEAT, false);
+
+            shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::MaskTexture), QT_MASK_TEXTURE_UNIT);
+            glDrawArrays(GL_TRIANGLES, 0, 6 * glyphs.size());
+
+            shaderManager->setMaskType(QGLEngineShaderManager::SubPixelMaskPass2);
+
+            if (compMode == QPainter::CompositionMode_Source) {
+                q->state()->opacity = oldOpacity;
+                opacityUniformDirty = true;
+                pensBrush = q->state()->pen.brush();
+                setBrush(&pensBrush);
+            }
+
+            compositionModeDirty = false;
+            prepareForDraw(false); // Text always causes src pixels to be transparent
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_ONE, GL_ONE);
+        }
+        compositionModeDirty = true;
+    } else {
+        // Greyscale/mono glyphs
+
+        shaderManager->setMaskType(QGLEngineShaderManager::PixelMask);
+        prepareForDraw(false); // Text always causes src pixels to be transparent
+    }
+    //### TODO: Gamma correction
+
+    glActiveTexture(GL_TEXTURE0 + QT_MASK_TEXTURE_UNIT);
+    glBindTexture(GL_TEXTURE_2D, cache->texture());
+    updateTextureFilter(GL_TEXTURE_2D, GL_REPEAT, false);
+
+    shaderManager->currentProgram()->setUniformValue(location(QGLEngineShaderManager::MaskTexture), QT_MASK_TEXTURE_UNIT);
+    glDrawArrays(GL_TRIANGLES, 0, 6 * glyphs.size());
+
+    if (inRenderText)
+        restoreDepthRangeForRenderText();
+}
+
+void QGL2PaintEngineEx::drawPixmaps(const QDrawPixmaps::Data *drawingData, int dataCount, const QPixmap &pixmap, QDrawPixmaps::DrawingHints hints)
+{
+    // Use fallback for extended composition modes.
+    if (state()->composition_mode > QPainter::CompositionMode_Plus) {
+        QPaintEngineEx::drawPixmaps(drawingData, dataCount, pixmap, hints);
+        return;
+    }
+
+    Q_D(QGL2PaintEngineEx);
+
+    GLfloat dx = 1.0f / pixmap.size().width();
+    GLfloat dy = 1.0f / pixmap.size().height();
+
+    d->vertexCoordinateArray.clear();
+    d->textureCoordinateArray.clear();
+    d->opacityArray.reset();
+
+    bool allOpaque = true;
+
+    for (int i = 0; i < dataCount; ++i) {
+        qreal s = 0;
+        qreal c = 1;
+        if (drawingData[i].rotation != 0) {
+            s = qFastSin(drawingData[i].rotation * Q_PI / 180);
+            c = qFastCos(drawingData[i].rotation * Q_PI / 180);
+        }
+
+        qreal right = 0.5 * drawingData[i].scaleX * drawingData[i].source.width();
+        qreal bottom = 0.5 * drawingData[i].scaleY * drawingData[i].source.height();
+        QGLPoint bottomRight(right * c - bottom * s, right * s + bottom * c);
+        QGLPoint bottomLeft(-right * c - bottom * s, -right * s + bottom * c);
+
+        d->vertexCoordinateArray.lineToArray(bottomRight.x + drawingData[i].point.x(), bottomRight.y + drawingData[i].point.y());
+        d->vertexCoordinateArray.lineToArray(-bottomLeft.x + drawingData[i].point.x(), -bottomLeft.y + drawingData[i].point.y());
+        d->vertexCoordinateArray.lineToArray(-bottomRight.x + drawingData[i].point.x(), -bottomRight.y + drawingData[i].point.y());
+        d->vertexCoordinateArray.lineToArray(-bottomRight.x + drawingData[i].point.x(), -bottomRight.y + drawingData[i].point.y());
+        d->vertexCoordinateArray.lineToArray(bottomLeft.x + drawingData[i].point.x(), bottomLeft.y + drawingData[i].point.y());
+        d->vertexCoordinateArray.lineToArray(bottomRight.x + drawingData[i].point.x(), bottomRight.y + drawingData[i].point.y());
+
+        QGLRect src(drawingData[i].source.left() * dx, drawingData[i].source.top() * dy,
+                    drawingData[i].source.right() * dx, drawingData[i].source.bottom() * dy);
+
+        d->textureCoordinateArray.lineToArray(src.right, src.bottom);
+        d->textureCoordinateArray.lineToArray(src.right, src.top);
+        d->textureCoordinateArray.lineToArray(src.left, src.top);
+        d->textureCoordinateArray.lineToArray(src.left, src.top);
+        d->textureCoordinateArray.lineToArray(src.left, src.bottom);
+        d->textureCoordinateArray.lineToArray(src.right, src.bottom);
+
+        qreal opacity = drawingData[i].opacity * state()->opacity;
+        d->opacityArray << opacity << opacity << opacity << opacity << opacity << opacity;
+        allOpaque &= (opacity >= 0.99f);
+    }
+
+    ensureActive();
+
+    QGLContext *ctx = d->ctx;
+    glActiveTexture(GL_TEXTURE0 + QT_IMAGE_TEXTURE_UNIT);
+    QGLTexture *texture = ctx->d_func()->bindTexture(pixmap, GL_TEXTURE_2D, GL_RGBA,
+                                                     QGLContext::InternalBindOption
+                                                     | QGLContext::CanFlipNativePixmapBindOption);
+
+    if (texture->options & QGLContext::InvertedYBindOption) {
+        // Flip texture y-coordinate.
+        QGLPoint *data = d->textureCoordinateArray.data();
+        for (int i = 0; i < 6 * dataCount; ++i)
+            data[i].y = 1 - data[i].y;
+    }
+
+    d->transferMode(ImageArrayDrawingMode);
+
+    bool isBitmap = pixmap.isQBitmap();
+    bool isOpaque = !isBitmap && (!pixmap.hasAlphaChannel() || (hints & QDrawPixmaps::OpaqueHint)) && allOpaque;
+
+    d->updateTextureFilter(GL_TEXTURE_2D, GL_CLAMP_TO_EDGE,
+                           state()->renderHints & QPainter::SmoothPixmapTransform, texture->id);
+
+    // Setup for texture drawing
+    d->shaderManager->setSrcPixelType(isBitmap ? QGLEngineShaderManager::PatternSrc : QGLEngineShaderManager::ImageSrc);
+    if (d->prepareForDraw(isOpaque))
+        d->shaderManager->currentProgram()->setUniformValue(d->location(QGLEngineShaderManager::ImageTexture), QT_IMAGE_TEXTURE_UNIT);
+
+    if (isBitmap) {
+        QColor col = qt_premultiplyColor(state()->pen.color(), (GLfloat)state()->opacity);
+        d->shaderManager->currentProgram()->setUniformValue(d->location(QGLEngineShaderManager::PatternColor), col);
+    }
+
+    glDrawArrays(GL_TRIANGLES, 0, 6 * dataCount);
+}
+
+bool QGL2PaintEngineEx::begin(QPaintDevice *pdev)
+{
+    Q_D(QGL2PaintEngineEx);
+
+//     qDebug("QGL2PaintEngineEx::begin()");
+    if (pdev->devType() == QInternal::OpenGL)
+        d->device = static_cast<QGLPaintDevice*>(pdev);
+    else
+        d->device = QGLPaintDevice::getDevice(pdev);
+
+    if (!d->device)
+        return false;
+
+    d->ctx = d->device->context();
+    d->ctx->d_ptr->active_engine = this;
+
+    const QSize sz = d->device->size();
+    d->width = sz.width();
+    d->height = sz.height();
+    d->mode = BrushDrawingMode;
+    d->brushTextureDirty = true;
+    d->brushUniformsDirty = true;
+    d->matrixDirty = true;
+    d->compositionModeDirty = true;
+    d->opacityUniformDirty = true;
+    d->needsSync = true;
+    d->use_system_clip = !systemClip().isEmpty();
+
+    d->dirtyStencilRegion = QRect(0, 0, d->width, d->height);
+    d->stencilClean = true;
+
+    // Calling begin paint should make the correct context current. So, any
+    // code which calls into GL or otherwise needs a current context *must*
+    // go after beginPaint:
+    d->device->beginPaint();
+
+#if !defined(QT_OPENGL_ES_2)
+    bool success = qt_resolve_version_2_0_functions(d->ctx);
+    Q_ASSERT(success);
+    Q_UNUSED(success);
+#endif
+
+    d->shaderManager = new QGLEngineShaderManager(d->ctx);
+
+    if (!d->inRenderText) {
+        glDisable(GL_STENCIL_TEST);
+        glDisable(GL_DEPTH_TEST);
+        glDisable(GL_SCISSOR_TEST);
+    }
+
+#if !defined(QT_OPENGL_ES_2)
+    glDisable(GL_MULTISAMPLE);
+#endif
+
+    d->glyphCacheType = QFontEngineGlyphCache::Raster_A8;
+
+#if !defined(QT_OPENGL_ES_2)
+    if (!d->device->format().alpha()
+#if defined(Q_WS_WIN)
+        && qt_cleartype_enabled
+#endif
+       ) {
+        d->glyphCacheType = QFontEngineGlyphCache::Raster_RGBMask;
+    }
+#endif
+
+    return true;
+}
+
+bool QGL2PaintEngineEx::end()
+{
+    Q_D(QGL2PaintEngineEx);
+    QGLContext *ctx = d->ctx;
+
+    glUseProgram(0);
+    d->transferMode(BrushDrawingMode);
+    d->device->endPaint();
+
+#if defined(Q_WS_X11)
+    // On some (probably all) drivers, deleting an X pixmap which has been bound to a texture
+    // before calling glFinish/swapBuffers renders garbage. Presumably this is because X deletes
+    // the pixmap behind the driver's back before it's had a chance to use it. To fix this, we
+    // reference all QPixmaps which have been bound to stop them being deleted and only deref
+    // them here, after swapBuffers, where they can be safely deleted.
+    ctx->d_func()->boundPixmaps.clear();
+#endif
+    d->ctx->d_ptr->active_engine = 0;
+
+    d->resetGLState();
+
+    delete d->shaderManager;
+    d->shaderManager = 0;
+
+    return false;
+}
+
+void QGL2PaintEngineEx::ensureActive()
+{
+    Q_D(QGL2PaintEngineEx);
+    QGLContext *ctx = d->ctx;
+
+    if (isActive() && ctx->d_ptr->active_engine != this) {
+        ctx->d_ptr->active_engine = this;
+        d->needsSync = true;
+    }
+
+    d->device->ensureActiveTarget();
+
+    if (d->needsSync) {
+        d->transferMode(BrushDrawingMode);
+        glViewport(0, 0, d->width, d->height);
+        d->needsSync = false;
+        d->shaderManager->setDirty();
+        setState(state());
+    }
+}
+
+void QGL2PaintEngineExPrivate::updateClipScissorTest()
+{
+    Q_Q(QGL2PaintEngineEx);
+    if (q->state()->clipTestEnabled) {
+        glEnable(GL_STENCIL_TEST);
+        glStencilFunc(GL_LEQUAL, q->state()->currentClip, ~GL_STENCIL_HIGH_BIT);
+    } else {
+        glDisable(GL_STENCIL_TEST);
+        glStencilFunc(GL_ALWAYS, 0, 0xff);
+    }
+
+#ifdef QT_GL_NO_SCISSOR_TEST
+    currentScissorBounds = QRect(0, 0, width, height);
+#else
+    QRect bounds = q->state()->rectangleClip;
+    if (!q->state()->clipEnabled) {
+        if (use_system_clip)
+            bounds = systemClip.boundingRect();
+        else
+            bounds = QRect(0, 0, width, height);
+    } else {
+        if (use_system_clip)
+            bounds = bounds.intersected(systemClip.boundingRect());
+        else
+            bounds = bounds.intersected(QRect(0, 0, width, height));
+    }
+
+    currentScissorBounds = bounds;
+
+    if (bounds == QRect(0, 0, width, height)) {
+        glDisable(GL_SCISSOR_TEST);
+    } else {
+        glEnable(GL_SCISSOR_TEST);
+        setScissor(bounds);
+    }
+#endif
+}
+
+void QGL2PaintEngineExPrivate::setScissor(const QRect &rect)
+{
+    const int left = rect.left();
+    const int width = rect.width();
+    const int bottom = height - (rect.top() + rect.height());
+    const int height = rect.height();
+
+    glScissor(left, bottom, width, height);
+}
+
+void QGL2PaintEngineEx::clipEnabledChanged()
+{
+    Q_D(QGL2PaintEngineEx);
+
+    state()->clipChanged = true;
+
+    if (painter()->hasClipping())
+        d->regenerateClip();
+    else
+        d->systemStateChanged();
+}
+
+void QGL2PaintEngineExPrivate::clearClip(uint value)
+{
+    dirtyStencilRegion -= currentScissorBounds;
+
+    glStencilMask(0xff);
+    glClearStencil(value);
+    glClear(GL_STENCIL_BUFFER_BIT);
+    glStencilMask(0x0);
+
+    q->state()->needsClipBufferClear = false;
+}
+
+void QGL2PaintEngineExPrivate::writeClip(const QVectorPath &path, uint value)
+{
+    transferMode(BrushDrawingMode);
+
+    if (matrixDirty)
+        updateMatrix();
+
+    stencilClean = false;
+
+    const bool singlePass = !path.hasWindingFill()
+        && (((q->state()->currentClip == maxClip - 1) && q->state()->clipTestEnabled)
+            || q->state()->needsClipBufferClear);
+    const uint referenceClipValue = q->state()->needsClipBufferClear ? 1 : q->state()->currentClip;
+
+    if (q->state()->needsClipBufferClear)
+        clearClip(1);
+
+    if (path.isEmpty()) {
+        glEnable(GL_STENCIL_TEST);
+        glStencilFunc(GL_LEQUAL, value, ~GL_STENCIL_HIGH_BIT);
+        return;
+    }
+
+    if (q->state()->clipTestEnabled)
+        glStencilFunc(GL_LEQUAL, q->state()->currentClip, ~GL_STENCIL_HIGH_BIT);
+    else
+        glStencilFunc(GL_ALWAYS, 0, 0xff);
+
+    vertexCoordinateArray.clear();
+    vertexCoordinateArray.addPath(path, inverseScale, false);
+
+    if (!singlePass)
+        fillStencilWithVertexArray(vertexCoordinateArray, path.hasWindingFill());
+
+    glColorMask(false, false, false, false);
+    glEnable(GL_STENCIL_TEST);
+    useSimpleShader();
+
+    if (singlePass) {
+        // Under these conditions we can set the new stencil value in a single
+        // pass, by using the current value and the "new value" as the toggles
+
+        glStencilFunc(GL_LEQUAL, referenceClipValue, ~GL_STENCIL_HIGH_BIT);
+        glStencilOp(GL_KEEP, GL_INVERT, GL_INVERT);
+        glStencilMask(value ^ referenceClipValue);
+
+        drawVertexArrays(vertexCoordinateArray, GL_TRIANGLE_FAN);
+    } else {
+        glStencilOp(GL_KEEP, GL_REPLACE, GL_REPLACE);
+        glStencilMask(0xff);
+
+        if (!q->state()->clipTestEnabled && path.hasWindingFill()) {
+            // Pass when any clip bit is set, set high bit
+            glStencilFunc(GL_NOTEQUAL, GL_STENCIL_HIGH_BIT, ~GL_STENCIL_HIGH_BIT);
+            composite(vertexCoordinateArray.boundingRect());
+        }
+
+        // Pass when high bit is set, replace stencil value with new clip value
+        glStencilFunc(GL_NOTEQUAL, value, GL_STENCIL_HIGH_BIT);
+
+        composite(vertexCoordinateArray.boundingRect());
+    }
+
+    glStencilFunc(GL_LEQUAL, value, ~GL_STENCIL_HIGH_BIT);
+    glStencilMask(0);
+
+    glColorMask(true, true, true, true);
+}
+
+void QGL2PaintEngineEx::clip(const QVectorPath &path, Qt::ClipOperation op)
+{
+//     qDebug("QGL2PaintEngineEx::clip()");
+    Q_D(QGL2PaintEngineEx);
+
+    state()->clipChanged = true;
+
+    ensureActive();
+
+    if (op == Qt::ReplaceClip) {
+        op = Qt::IntersectClip;
+        if (d->hasClipOperations()) {
+            d->systemStateChanged();
+            state()->canRestoreClip = false;
+        }
+    }
+
+#ifndef QT_GL_NO_SCISSOR_TEST
+    if (!path.isEmpty() && op == Qt::IntersectClip && (path.shape() == QVectorPath::RectangleHint)) {
+        const QPointF* const points = reinterpret_cast<const QPointF*>(path.points());
+        QRectF rect(points[0], points[2]);
+
+        if (state()->matrix.type() <= QTransform::TxScale) {
+            state()->rectangleClip = state()->rectangleClip.intersected(state()->matrix.mapRect(rect).toRect());
+            d->updateClipScissorTest();
+            return;
+        }
+    }
+#endif
+
+    const QRect pathRect = state()->matrix.mapRect(path.controlPointRect()).toAlignedRect();
+
+    switch (op) {
+    case Qt::NoClip:
+        if (d->use_system_clip) {
+            state()->clipTestEnabled = true;
+            state()->currentClip = 1;
+        } else {
+            state()->clipTestEnabled = false;
+        }
+        state()->rectangleClip = QRect(0, 0, d->width, d->height);
+        state()->canRestoreClip = false;
+        d->updateClipScissorTest();
+        break;
+    case Qt::IntersectClip:
+        state()->rectangleClip = state()->rectangleClip.intersected(pathRect);
+        d->updateClipScissorTest();
+        d->resetClipIfNeeded();
+        ++d->maxClip;
+        d->writeClip(path, d->maxClip);
+        state()->currentClip = d->maxClip;
+        state()->clipTestEnabled = true;
+        break;
+    case Qt::UniteClip: {
+        d->resetClipIfNeeded();
+        ++d->maxClip;
+        if (state()->rectangleClip.isValid()) {
+            QPainterPath path;
+            path.addRect(state()->rectangleClip);
+
+            // flush the existing clip rectangle to the depth buffer
+            d->writeClip(qtVectorPathForPath(state()->matrix.inverted().map(path)), d->maxClip);
+        }
+
+        state()->clipTestEnabled = false;
+#ifndef QT_GL_NO_SCISSOR_TEST
+        QRect oldRectangleClip = state()->rectangleClip;
+
+        state()->rectangleClip = state()->rectangleClip.united(pathRect);
+        d->updateClipScissorTest();
+
+        QRegion extendRegion = QRegion(state()->rectangleClip) - oldRectangleClip;
+
+        if (!extendRegion.isEmpty()) {
+            QPainterPath extendPath;
+            extendPath.addRegion(extendRegion);
+
+            // first clear the depth buffer in the extended region
+            d->writeClip(qtVectorPathForPath(state()->matrix.inverted().map(extendPath)), 0);
+        }
+#endif
+        // now write the clip path
+        d->writeClip(path, d->maxClip);
+        state()->canRestoreClip = false;
+        state()->currentClip = d->maxClip;
+        state()->clipTestEnabled = true;
+        break;
+        }
+    default:
+        break;
+    }
+}
+
+void QGL2PaintEngineExPrivate::regenerateClip()
+{
+    systemStateChanged();
+    replayClipOperations();
+}
+
+void QGL2PaintEngineExPrivate::systemStateChanged()
+{
+    Q_Q(QGL2PaintEngineEx);
+
+    q->state()->clipChanged = true;
+
+    if (systemClip.isEmpty()) {
+        use_system_clip = false;
+    } else {
+        if (q->paintDevice()->devType() == QInternal::Widget && currentClipWidget) {
+            QWidgetPrivate *widgetPrivate = qt_widget_private(currentClipWidget->window());
+            use_system_clip = widgetPrivate->extra && widgetPrivate->extra->inRenderWithPainter;
+        } else {
+            use_system_clip = true;
+        }
+    }
+
+    q->state()->clipTestEnabled = false;
+    q->state()->needsClipBufferClear = true;
+
+    q->state()->currentClip = 1;
+    maxClip = 1;
+
+    q->state()->rectangleClip = use_system_clip ? systemClip.boundingRect() : QRect(0, 0, width, height);
+    updateClipScissorTest();
+
+    if (systemClip.numRects() == 1) {
+        if (systemClip.boundingRect() == QRect(0, 0, width, height))
+            use_system_clip = false;
+#ifndef QT_GL_NO_SCISSOR_TEST
+        // scissoring takes care of the system clip
+        return;
+#endif
+    }
+
+    if (use_system_clip) {
+        clearClip(0);
+
+        QPainterPath path;
+        path.addRegion(systemClip);
+
+        q->state()->currentClip = 0;
+        writeClip(qtVectorPathForPath(q->state()->matrix.inverted().map(path)), 1);
+        q->state()->currentClip = 1;
+        q->state()->clipTestEnabled = true;
+    }
+}
+
+void QGL2PaintEngineEx::setState(QPainterState *new_state)
+{
+    //     qDebug("QGL2PaintEngineEx::setState()");
+
+    Q_D(QGL2PaintEngineEx);
+
+    QOpenGL2PaintEngineState *s = static_cast<QOpenGL2PaintEngineState *>(new_state);
+    QOpenGL2PaintEngineState *old_state = state();
+
+    QPaintEngineEx::setState(s);
+
+    if (s->isNew) {
+        // Newly created state object.  The call to setState()
+        // will either be followed by a call to begin(), or we are
+        // setting the state as part of a save().
+        s->isNew = false;
+        return;
+    }
+
+    // Setting the state as part of a restore().
+
+    if (old_state == s || old_state->renderHintsChanged)
+        renderHintsChanged();
+
+    if (old_state == s || old_state->matrixChanged) {
+        d->matrixDirty = true;
+        d->simpleShaderMatrixUniformDirty = true;
+        d->shaderMatrixUniformDirty = true;
+    }
+
+    if (old_state == s || old_state->compositionModeChanged)
+        d->compositionModeDirty = true;
+
+    if (old_state == s || old_state->opacityChanged)
+        d->opacityUniformDirty = true;
+
+    if (old_state == s || old_state->clipChanged) {
+        if (old_state && old_state != s && old_state->canRestoreClip) {
+            d->updateClipScissorTest();
+            glDepthFunc(GL_LEQUAL);
+        } else {
+            d->regenerateClip();
+        }
+    }
+}
+
+QPainterState *QGL2PaintEngineEx::createState(QPainterState *orig) const
+{
+    if (orig)
+        const_cast<QGL2PaintEngineEx *>(this)->ensureActive();
+
+    QOpenGL2PaintEngineState *s;
+    if (!orig)
+        s = new QOpenGL2PaintEngineState();
+    else
+        s = new QOpenGL2PaintEngineState(*static_cast<QOpenGL2PaintEngineState *>(orig));
+
+    s->matrixChanged = false;
+    s->compositionModeChanged = false;
+    s->opacityChanged = false;
+    s->renderHintsChanged = false;
+    s->clipChanged = false;
+
+    return s;
+}
+
+void QGL2PaintEngineEx::setRenderTextActive(bool active)
+{
+    Q_D(QGL2PaintEngineEx);
+    d->inRenderText = active;
+}
+
+QOpenGL2PaintEngineState::QOpenGL2PaintEngineState(QOpenGL2PaintEngineState &other)
+    : QPainterState(other)
+{
+    isNew = true;
+    needsClipBufferClear = other.needsClipBufferClear;
+    clipTestEnabled = other.clipTestEnabled;
+    currentClip = other.currentClip;
+    canRestoreClip = other.canRestoreClip;
+    rectangleClip = other.rectangleClip;
+}
+
+QOpenGL2PaintEngineState::QOpenGL2PaintEngineState()
+{
+    isNew = true;
+    needsClipBufferClear = true;
+    clipTestEnabled = false;
+    canRestoreClip = true;
+}
+
+QOpenGL2PaintEngineState::~QOpenGL2PaintEngineState()
+{
+}
+
+QT_END_NAMESPACE
+
+#include "qpaintengineex_opengl2.moc"