Merge branch '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-2 into 4.7-integration

* '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-2: (24 commits)
  Stabilize tst_QColumnView::parentCurrentIndex
  Really fix tst_QDockWidget::taskQTBUG_9758_undockedGeometry on Linux
  Fix typos in Elastic Nodes example documentation.
  Made paint engine texture drawing work in GL ES 2 and updated docs.
  Opt out of visual-config size checks with extension
  Fix off-by-one in text layouts and widget size hints on Mac
  Stabilize tst_QDockWidget::taskQTBUG_9758_undockedGeometry
  Mark QFileDialog::Options as a Q_FLAGS
  fix tst_QDockWidget::taskQTBUG_9758_undockedGeometry on Linux
  Fixed scrolling bugs in widget graphics effect backend.
  Fixed source pixmap bug in widget graphics effect backend.
  Fix crash with stylesheet if widget change style in the changeEvent
  Fix textdrawing under GL on N900.
  Fixed bug in QIODevice::read after first reading 0 bytes.
  Fix auto-test failure on Mac/Linux/QWS.
  Some EGL implementations does not return a EGLNativeDisplayType
  Fixed the sizing of the dock area with fixed size dock widgets
  QSortFilterProxyModel: Warning or assert failure
  Performance issue with QGraphicsItem::ItemClipsChildrenToShape.
  Fixes crash in QGraphicsItem::mouseMove for untransformable items.
  ...

2 files changed, 59 insertions, 32 deletions

diff --git a/src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp b/src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp
index 994c1c9..452d37d 100644
--- a/src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp
+++ b/src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp
@@ -42,6 +42,10 @@
 #include "qtextureglyphcache_gl_p.h"
 #include "qpaintengineex_opengl2_p.h"
 
+#if defined QT_OPENGL_ES_2 && !defined(QT_NO_EGL)
+#include "private/qeglcontext_p.h"
+#endif
+
 QT_BEGIN_NAMESPACE
 
 #ifdef Q_WS_WIN
@@ -49,12 +53,27 @@ extern Q_GUI_EXPORT bool qt_cleartype_enabled;
 #endif
 
 QGLTextureGlyphCache::QGLTextureGlyphCache(QGLContext *context, QFontEngineGlyphCache::Type type, const QTransform &matrix)
-    : QTextureGlyphCache(type, matrix)
+    : QImageTextureGlyphCache(type, matrix)
     , ctx(context)
     , m_width(0)
     , m_height(0)
+    , m_broken_fbo_readback(false)
 {
-    glGenFramebuffers(1, &m_fbo);
+    // broken FBO readback is a bug in the SGX 1.3 and 1.4 drivers for the N900 where
+    // copying between FBO's is broken if the texture is either GL_ALPHA or POT. The
+    // workaround is to use a system-memory copy of the glyph cache for this device.
+    // Switching to NPOT and GL_RGBA would both cost a lot more graphics memory and
+    // be slower, so that is not desireable.
+#if defined QT_OPENGL_ES_2 && !defined(QT_NO_EGL)
+    if (QByteArray((char*) glGetString(GL_RENDERER)).contains("SGX")) {
+        QGLContextPrivate *ctxd = context->d_func();
+        m_broken_fbo_readback = QByteArray((char *) eglQueryString(ctxd->eglContext->display(), EGL_VERSION)).contains("1.3");
+    }
+#endif
+
+    if (!m_broken_fbo_readback)
+        glGenFramebuffers(1, &m_fbo);
+
     connect(QGLSignalProxy::instance(), SIGNAL(aboutToDestroyContext(const QGLContext*)),
             SLOT(contextDestroyed(const QGLContext*)));
 }
@@ -63,7 +82,9 @@ QGLTextureGlyphCache::~QGLTextureGlyphCache()
 {
     if (ctx) {
         QGLShareContextScope scope(ctx);
-        glDeleteFramebuffers(1, &m_fbo);
+
+        if (!m_broken_fbo_readback)
+            glDeleteFramebuffers(1, &m_fbo);
 
         if (m_width || m_height)
             glDeleteTextures(1, &m_texture);
@@ -72,6 +93,12 @@ QGLTextureGlyphCache::~QGLTextureGlyphCache()
 
 void QGLTextureGlyphCache::createTextureData(int width, int height)
 {
+    // create in QImageTextureGlyphCache baseclass is meant to be called
+    // only to create the initial image and does not preserve the content,
+    // so we don't call when this function is called from resize.
+    if (m_broken_fbo_readback && image().isNull())
+        QImageTextureGlyphCache::createTextureData(width, height);
+
     glGenTextures(1, &m_texture);
     glBindTexture(GL_TEXTURE_2D, m_texture);
 
@@ -93,14 +120,22 @@ void QGLTextureGlyphCache::createTextureData(int width, int height)
 
 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);
+    
+    if (m_broken_fbo_readback) {
+        QImageTextureGlyphCache::resizeTextureData(width, height);
+        Q_ASSERT(image().depth() == 8);
+        glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, oldWidth, oldHeight, GL_ALPHA, GL_UNSIGNED_BYTE, image().constBits());
+        glDeleteTextures(1, &oldTexture);
+        return;
+    }
+
+    // ### the QTextureGlyphCache API needs to be reworked to allow
+    // ### resizeTextureData to fail
 
     glBindFramebuffer(GL_FRAMEBUFFER_EXT, m_fbo);
 
@@ -159,20 +194,7 @@ void QGLTextureGlyphCache::resizeTextureData(int width, int height)
 
     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);
@@ -187,6 +209,21 @@ void QGLTextureGlyphCache::resizeTextureData(int width, int height)
 
 void QGLTextureGlyphCache::fillTexture(const Coord &c, glyph_t glyph)
 {
+    if (m_broken_fbo_readback) {
+        QImageTextureGlyphCache::fillTexture(c, glyph);
+
+        glBindTexture(GL_TEXTURE_2D, m_texture);
+        const QImage &texture = image();
+        const uchar *bits = texture.constBits();
+        bits += c.y * texture.bytesPerLine() + c.x;
+        for (int i=0; i<c.h; ++i) {
+            glTexSubImage2D(GL_TEXTURE_2D, 0, c.x, c.y + i, c.w, 1, GL_ALPHA, GL_UNSIGNED_BYTE, bits);
+            bits += texture.bytesPerLine();
+        }
+
+        return;
+    }
+
     QImage mask = textureMapForGlyph(glyph);
     const int maskWidth = mask.width();
     const int maskHeight = mask.height();
@@ -235,17 +272,6 @@ void QGLTextureGlyphCache::fillTexture(const Coord &c, glyph_t glyph)
     }
 }
 
-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
-}
-
 int QGLTextureGlyphCache::glyphPadding() const
 {
     return 1;
diff --git a/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h b/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h
index 75c2bb1..efb7435 100644
--- a/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h
+++ b/src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h
@@ -62,7 +62,7 @@ QT_BEGIN_NAMESPACE
 
 class QGL2PaintEngineExPrivate;
 
-class Q_OPENGL_EXPORT QGLTextureGlyphCache : public QObject, public QTextureGlyphCache
+class Q_OPENGL_EXPORT QGLTextureGlyphCache : public QObject, public QImageTextureGlyphCache
 {
     Q_OBJECT
 public:
@@ -72,7 +72,6 @@ public:
     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;
     virtual int glyphPadding() const;
 
     inline GLuint texture() const { return m_texture; }
@@ -116,6 +115,8 @@ private:
     int m_height;
 
     QGLShaderProgram *m_program;
+
+    bool m_broken_fbo_readback;
 };
 
 QT_END_NAMESPACE