1 files changed, 59 insertions, 38 deletions

diff --git a/src/gui/painting/qplatformbackingstore.cpp b/src/gui/painting/qplatformbackingstore.cpp
index 5b6c4bb83d..e5b06f499c 100644
--- a/src/gui/painting/qplatformbackingstore.cpp
+++ b/src/gui/painting/qplatformbackingstore.cpp
@@ -90,6 +90,7 @@ struct QBackingstoreTextureInfo
 {
     GLuint textureId;
     QRect rect;
+    bool stacksOnTop;
 };
 
 Q_DECLARE_TYPEINFO(QBackingstoreTextureInfo, Q_MOVABLE_TYPE);
@@ -127,6 +128,12 @@ GLuint QPlatformTextureList::textureId(int index) const
     return d->textures.at(index).textureId;
 }
 
+bool QPlatformTextureList::stacksOnTop(int index) const
+{
+    Q_D(const QPlatformTextureList);
+    return d->textures.at(index).stacksOnTop;
+}
+
 QRect QPlatformTextureList::geometry(int index) const
 {
     Q_D(const QPlatformTextureList);
@@ -148,12 +155,13 @@ bool QPlatformTextureList::isLocked() const
     return d->locked;
 }
 
-void QPlatformTextureList::appendTexture(GLuint textureId, const QRect &geometry)
+void QPlatformTextureList::appendTexture(GLuint textureId, const QRect &geometry, bool stacksOnTop)
 {
     Q_D(QPlatformTextureList);
     QBackingstoreTextureInfo bi;
     bi.textureId = textureId;
     bi.rect = geometry;
+    bi.stacksOnTop = stacksOnTop;
     d->textures.append(bi);
 }
 
@@ -238,29 +246,39 @@ void QPlatformBackingStore::composeAndFlush(QWindow *window, const QRegion &regi
 
     QRect windowRect(QPoint(), window->size() * window->devicePixelRatio());
 
+    // Textures for renderToTexture widgets.
     for (int i = 0; i < textures->count(); ++i) {
-        GLuint textureId = textures->textureId(i);
-        funcs->glBindTexture(GL_TEXTURE_2D, textureId);
-
-        QRect targetRect = deviceRect(textures->geometry(i), window);
-        QMatrix4x4 target = QOpenGLTextureBlitter::targetTransform(targetRect, windowRect);
-        d_ptr->blitter->blit(textureId, target, QOpenGLTextureBlitter::OriginBottomLeft);
+        if (!textures->stacksOnTop(i)) {
+            QRect targetRect = deviceRect(textures->geometry(i), window);
+            QMatrix4x4 target = QOpenGLTextureBlitter::targetTransform(targetRect, windowRect);
+            d_ptr->blitter->blit(textures->textureId(i), target, QOpenGLTextureBlitter::OriginBottomLeft);
+        }
     }
 
-    GLuint textureId = toTexture(deviceRegion(region, window), &d_ptr->textureSize);
-    if (!textureId)
-        return;
-
     funcs->glEnable(GL_BLEND);
     funcs->glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
-    QMatrix4x4 target = QOpenGLTextureBlitter::targetTransform(QRect(QPoint(), d_ptr->textureSize), windowRect);
-    d_ptr->blitter->setSwizzleRB(true);
-    d_ptr->blitter->blit(textureId, target, QOpenGLTextureBlitter::OriginTopLeft);
-    d_ptr->blitter->setSwizzleRB(false);
+    // Backingstore texture with the normal widgets.
+    GLuint textureId = toTexture(deviceRegion(region, window), &d_ptr->textureSize);
+    if (textureId) {
+        QMatrix4x4 target = QOpenGLTextureBlitter::targetTransform(QRect(QPoint(), d_ptr->textureSize), windowRect);
+        d_ptr->blitter->setSwizzleRB(true);
+        d_ptr->blitter->blit(textureId, target, QOpenGLTextureBlitter::OriginTopLeft);
+        d_ptr->blitter->setSwizzleRB(false);
+    }
+
+    // Textures for renderToTexture widgets that have WA_AlwaysStackOnTop set.
+    for (int i = 0; i < textures->count(); ++i) {
+        if (textures->stacksOnTop(i)) {
+            QRect targetRect = deviceRect(textures->geometry(i), window);
+            QMatrix4x4 target = QOpenGLTextureBlitter::targetTransform(targetRect, windowRect);
+            d_ptr->blitter->blit(textures->textureId(i), target, QOpenGLTextureBlitter::OriginBottomLeft);
+        }
+    }
 
     funcs->glDisable(GL_BLEND);
     d_ptr->blitter->release();
+
     context->swapBuffers(window);
 }
 
@@ -321,8 +339,8 @@ GLuint QPlatformBackingStore::toTexture(const QRegion &dirtyRegion, QSize *textu
 #endif
         funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
         funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-        funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-        funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+        funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+        funcs->glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 
         funcs->glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, imageSize.width(), imageSize.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE,
                             const_cast<uchar*>(image.constBits()));
@@ -334,29 +352,32 @@ GLuint QPlatformBackingStore::toTexture(const QRegion &dirtyRegion, QSize *textu
         QRect rect = dirtyRegion.boundingRect() & imageRect;
 
 #ifndef QT_OPENGL_ES_2
-        funcs->glPixelStorei(GL_UNPACK_ROW_LENGTH, image.width());
-        funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, rect.x(), rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
-                               image.constScanLine(rect.y()) + rect.x() * 4);
-        funcs->glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
-#else
-        // if the rect is wide enough it's cheaper to just
-        // extend it instead of doing an image copy
-        if (rect.width() >= imageRect.width() / 2) {
-            rect.setX(0);
-            rect.setWidth(imageRect.width());
-        }
-
-        // if the sub-rect is full-width we can pass the image data directly to
-        // OpenGL instead of copying, since there's no gap between scanlines
-
-        if (rect.width() == imageRect.width()) {
-            funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, 0, rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
-                                   image.constScanLine(rect.y()));
-        } else {
+        if (!QOpenGLContext::currentContext()->isOpenGLES()) {
+            funcs->glPixelStorei(GL_UNPACK_ROW_LENGTH, image.width());
             funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, rect.x(), rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
-                                   image.copy(rect).constBits());
-        }
+                                   image.constScanLine(rect.y()) + rect.x() * 4);
+            funcs->glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
+        } else
 #endif
+        {
+            // if the rect is wide enough it's cheaper to just
+            // extend it instead of doing an image copy
+            if (rect.width() >= imageRect.width() / 2) {
+                rect.setX(0);
+                rect.setWidth(imageRect.width());
+            }
+
+            // if the sub-rect is full-width we can pass the image data directly to
+            // OpenGL instead of copying, since there's no gap between scanlines
+
+            if (rect.width() == imageRect.width()) {
+                funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, 0, rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
+                                       image.constScanLine(rect.y()));
+            } else {
+                funcs->glTexSubImage2D(GL_TEXTURE_2D, 0, rect.x(), rect.y(), rect.width(), rect.height(), GL_RGBA, GL_UNSIGNED_BYTE,
+                                       image.copy(rect).constBits());
+            }
+        }
     }
 
     return d_ptr->textureId;