Implement more Compositor methods for software mode

Add implementations of devicePixelRatio, textureSize, hasAlphaChannel
also for software mode. Rename textureSize to just size.

Change-Id: I5c515e4fed3330e0ecbfc17e7ec092245a13e619
Reviewed-by: Michal Klocek <michal.klocek@qt.io>

7 files changed, 36 insertions, 38 deletions

diff --git a/src/core/compositor/compositor.cpp b/src/core/compositor/compositor.cpp
index c45c02844..655126f20 100644
--- a/src/core/compositor/compositor.cpp
+++ b/src/core/compositor/compositor.cpp
@@ -172,12 +172,6 @@ Compositor::Handle<Compositor::Observer> Compositor::observer()
     return nullptr;
 }
 
-float Compositor::devicePixelRatio()
-{
-    Q_UNREACHABLE();
-    return 1;
-}
-
 QImage Compositor::image()
 {
     Q_UNREACHABLE();
@@ -195,18 +189,6 @@ int Compositor::textureId()
     return 0;
 }
 
-QSize Compositor::textureSize()
-{
-    Q_UNREACHABLE();
-    return {};
-}
-
-bool Compositor::hasAlphaChannel()
-{
-    Q_UNREACHABLE();
-    return false;
-}
-
 // static
 void Compositor::unlockBindings()
 {
diff --git a/src/core/compositor/compositor.h b/src/core/compositor/compositor.h
index d10cf2ef6..316178891 100644
--- a/src/core/compositor/compositor.h
+++ b/src/core/compositor/compositor.h
@@ -147,7 +147,19 @@ public:
     // Ratio of pixels to DIPs.
     //
     // Don't use the devicePixelRatio of QImage, it's always 1.
-    virtual float devicePixelRatio();
+    virtual float devicePixelRatio() = 0;
+
+    // Size of frame in pixels.
+    virtual QSize size() = 0;
+
+    // Whether frame needs an alpha channel.
+    //
+    // In software mode, the image format can be either
+    //   QImage::Format_ARGB32_Premultiplied or
+    //   QImage::Format_RGBA8888_Premultiplied
+    //
+    // In OpenGL mode, the texture format is either GL_RGBA or GL_RGB.
+    virtual bool hasAlphaChannel() = 0;
 
     // (Software) QImage of the frame.
     //
@@ -160,10 +172,8 @@ public:
     // (OpenGL) Wait on texture fence in Qt's current OpenGL context.
     virtual void waitForTexture();
 
-    // (OpenGL) Properties of the current frame.
+    // (OpenGL) Texture of the frame.
     virtual int textureId();
-    virtual QSize textureSize();
-    virtual bool hasAlphaChannel();
 
 protected:
     Compositor(Type type) : m_type(type) { }
diff --git a/src/core/compositor/display_gl_output_surface.cpp b/src/core/compositor/display_gl_output_surface.cpp
index f736bba79..05653149e 100644
--- a/src/core/compositor/display_gl_output_surface.cpp
+++ b/src/core/compositor/display_gl_output_surface.cpp
@@ -323,7 +323,7 @@ int DisplayGLOutputSurface::textureId()
     return m_frontBuffer ? m_frontBuffer->serviceId : 0;
 }
 
-QSize DisplayGLOutputSurface::textureSize()
+QSize DisplayGLOutputSurface::size()
 {
     return m_frontBuffer ? toQt(m_frontBuffer->shape.sizeInPixels) : QSize();
 }
diff --git a/src/core/compositor/display_gl_output_surface.h b/src/core/compositor/display_gl_output_surface.h
index 678d0cf5c..6b1b2e043 100644
--- a/src/core/compositor/display_gl_output_surface.h
+++ b/src/core/compositor/display_gl_output_surface.h
@@ -91,7 +91,7 @@ public:
     void swapFrame() override;
     void waitForTexture() override;
     int textureId() override;
-    QSize textureSize() override;
+    QSize size() override;
     bool hasAlphaChannel() override;
     float devicePixelRatio() override;
 
diff --git a/src/core/compositor/display_software_output_surface.cpp b/src/core/compositor/display_software_output_surface.cpp
index b1a357615..218bff94a 100644
--- a/src/core/compositor/display_software_output_surface.cpp
+++ b/src/core/compositor/display_software_output_surface.cpp
@@ -67,6 +67,8 @@ public:
     void swapFrame() override;
     QImage image() override;
     float devicePixelRatio() override;
+    QSize size() override;
+    bool hasAlphaChannel() override;
 
 private:
     mutable QMutex m_mutex;
@@ -154,6 +156,16 @@ float DisplaySoftwareOutputSurface::Device::devicePixelRatio()
     return m_imageDevicePixelRatio;
 }
 
+QSize DisplaySoftwareOutputSurface::Device::size()
+{
+    return m_image.size();
+}
+
+bool DisplaySoftwareOutputSurface::Device::hasAlphaChannel()
+{
+    return m_image.format() == QImage::Format_ARGB32_Premultiplied;
+}
+
 DisplaySoftwareOutputSurface::DisplaySoftwareOutputSurface()
     : SoftwareOutputSurface(std::make_unique<Device>())
 {}
diff --git a/src/webengine/render_widget_host_view_qt_delegate_quick.cpp b/src/webengine/render_widget_host_view_qt_delegate_quick.cpp
index 9ed660f2e..60340079f 100644
--- a/src/webengine/render_widget_host_view_qt_delegate_quick.cpp
+++ b/src/webengine/render_widget_host_view_qt_delegate_quick.cpp
@@ -357,17 +357,14 @@ QSGNode *RenderWidgetHostViewQtDelegateQuick::updatePaintNode(QSGNode *oldNode,
 
     comp->swapFrame();
 
+    QSize texSize = comp->size();
+    QSizeF texSizeInDips = QSizeF(texSize) / comp->devicePixelRatio();
+    node->setRect(QRectF(QPointF(0, 0), texSizeInDips));
+
     if (comp->type() == Compositor::Type::Software) {
         QImage image = comp->image();
-        float pixPerDip = comp->devicePixelRatio();
-        QSizeF sizeInDips = QSizeF(image.size()) / pixPerDip;
-        node->setRect(QRectF(QPointF(0, 0), sizeInDips));
         node->setTexture(win->createTextureFromImage(image));
     } else if (comp->type() == Compositor::Type::OpenGL) {
-        QSize texSize = comp->textureSize();
-        float pixPerDip = comp->devicePixelRatio();
-        QSizeF sizeInDips = QSizeF(texSize) / pixPerDip;
-        node->setRect(QRectF(QPointF(0, 0), sizeInDips));
         QQuickWindow::CreateTextureOptions texOpts;
         if (comp->hasAlphaChannel())
             texOpts.setFlag(QQuickWindow::TextureHasAlphaChannel);
diff --git a/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp b/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
index 853553c47..f9a7b036e 100644
--- a/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
+++ b/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
@@ -119,17 +119,14 @@ protected:
 
         comp->swapFrame();
 
+        QSize texSize = comp->size();
+        QSizeF texSizeInDips = QSizeF(texSize) / comp->devicePixelRatio();
+        node->setRect(QRectF(QPointF(0, 0), texSizeInDips));
+
         if (comp->type() == Compositor::Type::Software) {
             QImage image = comp->image();
-            float pixPerDip = comp->devicePixelRatio();
-            QSizeF sizeInDips = QSizeF(image.size()) / pixPerDip;
-            node->setRect(QRectF(QPointF(0, 0), sizeInDips));
             node->setTexture(win->createTextureFromImage(image));
         } else if (comp->type() == Compositor::Type::OpenGL) {
-            QSize texSize = comp->textureSize();
-            float pixPerDip = comp->devicePixelRatio();
-            QSizeF sizeInDips = QSizeF(texSize) / pixPerDip;
-            node->setRect(QRectF(QPointF(0, 0), sizeInDips));
             QQuickWindow::CreateTextureOptions texOpts;
             if (comp->hasAlphaChannel())
                 texOpts.setFlag(QQuickWindow::TextureHasAlphaChannel);