Merge remote branch 'qt/master' into lighthouse-master

Conflicts:
	src/opengl/qwindowsurface_gl.cpp

1 files changed, 84 insertions, 56 deletions

diff --git a/src/opengl/qwindowsurface_gl.cpp b/src/opengl/qwindowsurface_gl.cpp
index 29c4477..47f36dd 100644
--- a/src/opengl/qwindowsurface_gl.cpp
+++ b/src/opengl/qwindowsurface_gl.cpp
@@ -194,7 +194,7 @@ public:
             widget = new QGLWidget(QGLFormat(QGL::SingleBuffer | QGL::NoDepthBuffer | QGL::NoStencilBuffer));
             widget->resize(1, 1);
 
-            // We dont need this internal widget to appear in QApplication::topLevelWidgets()
+            // We don't need this internal widget to appear in QApplication::topLevelWidgets()
             if (QWidgetPrivate::allWidgets)
                 QWidgetPrivate::allWidgets->remove(widget);
             initializing = false;
@@ -275,6 +275,8 @@ struct QGLWindowSurfacePrivate
     QRegion paintedRegion;
     QSize size;
 
+    QSize textureSize;
+
     QList<QImage> buffers;
     QGLWindowSurfaceGLPaintDevice glDevice;
     QGLWindowSurface* q_ptr;
@@ -316,6 +318,7 @@ QGLWindowSurface::QGLWindowSurface(QWidget *window)
     d_ptr->pb = 0;
     d_ptr->fbo = 0;
     d_ptr->ctx = 0;
+    d_ptr->tex_id = 0;
 #if defined (QT_OPENGL_ES_2)
     d_ptr->tried_fbo = true;
     d_ptr->tried_pb = true;
@@ -435,7 +438,7 @@ static void drawTexture(const QRectF &rect, GLuint tex_id, const QSize &texSize,
 
 void QGLWindowSurface::beginPaint(const QRegion &)
 {
-    if (! context())
+    if (!context())
         return;
 
     int clearFlags = 0;
@@ -459,13 +462,42 @@ void QGLWindowSurface::endPaint(const QRegion &rgn)
     d_ptr->buffers.clear();
 }
 
-void QGLWindowSurface::flush(QWidget *widget, const QRegion &rgn, const QPoint &offset)
+static void blitTexture(QGLContext *ctx, GLuint texture, const QSize &viewport, const QSize &texSize, const QRect &targetRect, const QRect &sourceRect)
 {
-    if (context() && widget != window()) {
-        qWarning("No native child widget support in GL window surface without FBOs or pixel buffers");
-        return;
-    }
+    glDisable(GL_DEPTH_TEST);
+    glDisable(GL_SCISSOR_TEST);
+    glDisable(GL_BLEND);
+
+    glViewport(0, 0, viewport.width(), viewport.height());
+
+    QGLShaderProgram *blitProgram =
+        QGLEngineSharedShaders::shadersForContext(ctx)->blitProgram();
+    blitProgram->bind();
+    blitProgram->setUniformValue("imageTexture", 0 /*QT_IMAGE_TEXTURE_UNIT*/);
+
+    // The shader manager's blit program does not multiply the
+    // vertices by the pmv matrix, so we need to do the effect
+    // of the orthographic projection here ourselves.
+    QRectF r;
+    qreal w = viewport.width();
+    qreal h = viewport.height();
+    r.setLeft((targetRect.left() / w) * 2.0f - 1.0f);
+    if (targetRect.right() == (viewport.width() - 1))
+        r.setRight(1.0f);
+    else
+        r.setRight((targetRect.right() / w) * 2.0f - 1.0f);
+    r.setBottom((targetRect.top() / h) * 2.0f - 1.0f);
+    if (targetRect.bottom() == (viewport.height() - 1))
+        r.setTop(1.0f);
+    else
+        r.setTop((targetRect.bottom() / w) * 2.0f - 1.0f);
+
+    drawTexture(r, texture, texSize, sourceRect);
+}
+
 
+void QGLWindowSurface::flush(QWidget *widget, const QRegion &rgn, const QPoint &offset)
+{
     //### Find out why d_ptr->geometry_updated isn't always false.
     // flush() should not be called when d_ptr->geometry_updated is true. It assumes that either
     // d_ptr->fbo or d_ptr->pb is allocated and has the correct size.
@@ -541,12 +573,29 @@ void QGLWindowSurface::flush(QWidget *widget, const QRegion &rgn, const QPoint &
                 }
             }
 #endif
-            if (hasPartialUpdateSupport() &&
-                d_ptr->paintedRegion.boundingRect().width() * d_ptr->paintedRegion.boundingRect().height() <
-                geometry().width() * geometry().height() * 0.2) {
-                context()->d_func()->swapRegion(&d_ptr->paintedRegion);             
-            } else
-                context()->swapBuffers();
+            bool doingPartialUpdate = hasPartialUpdateSupport() && br.width() * br.height() < parent->geometry().width() * parent->geometry().height() * 0.2;
+            QGLContext *ctx = reinterpret_cast<QGLContext *>(parent->d_func()->extraData()->glContext);
+            if (widget != window()) {
+                if (initializeOffscreenTexture(window()->size()))
+                    qWarning() << "QGLWindowSurface: Flushing to native child widget, may lead to significant performance loss";
+                glBindTexture(target, d_ptr->tex_id);
+
+                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);
+
+                ctx->makeCurrent();
+                if (doingPartialUpdate)
+                    blitTexture(ctx, d_ptr->tex_id, parent->size(), window()->size(), rect, br);
+                else
+                    blitTexture(ctx, d_ptr->tex_id, parent->size(), window()->size(), parent->rect(), parent->rect().translated(offset + wOffset));
+            }
+
+            if (doingPartialUpdate)
+                ctx->d_func()->swapRegion(br);
+            else
+                ctx->swapBuffers();
 
             d_ptr->paintedRegion = QRegion();
         } else {
@@ -672,38 +721,10 @@ void QGLWindowSurface::flush(QWidget *widget, const QRegion &rgn, const QPoint &
     else if (d_ptr->fbo) {
         Q_UNUSED(target);
 
-        GLuint texture = d_ptr->fbo->texture();
-
-        glDisable(GL_DEPTH_TEST);
-
         if (d_ptr->fbo->isBound())
             d_ptr->fbo->release();
 
-        glViewport(0, 0, size.width(), size.height());
-
-        QGLShaderProgram *blitProgram =
-            QGLEngineSharedShaders::shadersForContext(ctx)->blitProgram();
-        blitProgram->bind();
-        blitProgram->setUniformValue("imageTexture", 0 /*QT_IMAGE_TEXTURE_UNIT*/);
-
-        // The shader manager's blit program does not multiply the
-        // vertices by the pmv matrix, so we need to do the effect
-        // of the orthographic projection here ourselves.
-        QRectF r;
-        qreal w = size.width() ? size.width() : 1.0f;
-        qreal h = size.height() ? size.height() : 1.0f;
-        r.setLeft((rect.left() / w) * 2.0f - 1.0f);
-        if (rect.right() == (size.width() - 1))
-            r.setRight(1.0f);
-        else
-            r.setRight((rect.right() / w) * 2.0f - 1.0f);
-        r.setBottom((rect.top() / h) * 2.0f - 1.0f);
-        if (rect.bottom() == (size.height() - 1))
-            r.setTop(1.0f);
-        else
-            r.setTop((rect.bottom() / w) * 2.0f - 1.0f);
-
-        drawTexture(r, texture, window()->size(), br);
+        blitTexture(ctx, d_ptr->fbo->texture(), size, window()->size(), rect, br);
     }
 #endif
 
@@ -758,11 +779,8 @@ void QGLWindowSurface::updateGeometry() {
 
     if (d_ptr->ctx) {
 #ifndef QT_OPENGL_ES_2
-        if (d_ptr->destructive_swap_buffers) {
-            glBindTexture(target, d_ptr->tex_id);
-            glTexImage2D(target, 0, GL_RGBA, surfSize.width(), surfSize.height(), 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
-            glBindTexture(target, 0);
-        }
+        if (d_ptr->destructive_swap_buffers)
+            initializeOffscreenTexture(surfSize);
 #endif
         return;
     }
@@ -842,15 +860,8 @@ void QGLWindowSurface::updateGeometry() {
     ctx->makeCurrent();
 
 #ifndef QT_OPENGL_ES_2
-    if (d_ptr->destructive_swap_buffers) {
-        glGenTextures(1, &d_ptr->tex_id);
-        glBindTexture(target, d_ptr->tex_id);
-        glTexImage2D(target, 0, GL_RGBA, surfSize.width(), surfSize.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);
-    }
+    if (d_ptr->destructive_swap_buffers)
+        initializeOffscreenTexture(surfSize);
 #endif
 
     qDebug() << "QGLWindowSurface: Using plain widget as window surface" << this;;
@@ -858,6 +869,23 @@ void QGLWindowSurface::updateGeometry() {
     d_ptr->ctx->d_ptr->internal_context = true;
 }
 
+bool QGLWindowSurface::initializeOffscreenTexture(const QSize &size)
+{
+    if (size == d_ptr->textureSize)
+        return false;
+
+    glGenTextures(1, &d_ptr->tex_id);
+    glBindTexture(GL_TEXTURE_2D, d_ptr->tex_id);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, size.width(), size.height(), 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
+
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    glBindTexture(GL_TEXTURE_2D, 0);
+
+    d_ptr->textureSize = size;
+    return true;
+}
+
 bool QGLWindowSurface::scroll(const QRegion &area, int dx, int dy)
 {
     // this code randomly fails currently for unknown reasons