Client: Added CompositorWidget, testing it in ClientWindow

CompositorWidget uses a texture target for all its children.

ClientWindow is now set up to use a compositor for everything that
is not the game view. This should only be done when necessary, not
always as currently.

GuiRootWidget::addOnTop() was added so that widgets can be added
easily into the compositor or the root if a compositor is not in use.

doomsday/client/client.pro

@@ -420,6 +420,7 @@ DENG_HEADERS += \
     include/ui/widgets/buttonwidget.h \
     include/ui/widgets/choicewidget.h \
     include/ui/widgets/commandwidget.h \
+    include/ui/widgets/compositorwidget.h \
     include/ui/widgets/consolecommandwidget.h \
     include/ui/widgets/consolewidget.h \
     include/ui/widgets/cvarchoicewidget.h \
@@ -767,6 +768,7 @@ SOURCES += \
     src/ui/widgets/buttonwidget.cpp \
     src/ui/widgets/choicewidget.cpp \
     src/ui/widgets/commandwidget.cpp \
+    src/ui/widgets/compositorwidget.cpp \
     src/ui/widgets/consolecommandwidget.cpp \
     src/ui/widgets/consolewidget.cpp \
     src/ui/widgets/cvarchoicewidget.cpp \

doomsday/client/include/ui/clientwindow.h

@@ -78,6 +78,15 @@ class ClientWindow : public de::PersistentCanvasWindow,
     GameWidget &game();
     BusyWidget &busy();
 
+    /**
+     * Adds a widget to the widget tree so that it will be displayed over
+     * other widgets.
+     *
+     * @param widget  Widget to add on top of others. Ownership of the
+     *                widget taken by the new parent.
+     */
+    void addOnTop(GuiWidget *widget);
+
     /**
      * Installs a sidebar widget into the window. If there is an existing
      * sidebar, it will be deleted. Sidebar widgets are expected to control

doomsday/client/include/ui/framework/guirootwidget.h

@@ -26,6 +26,7 @@
 #include <de/Matrix>
 
 class ClientWindow;
+class GuiWidget;
 
 /**
  * Graphical root widget.
@@ -49,6 +50,13 @@ class GuiRootWidget : public de::RootWidget
      */
     ClientWindow &window();
 
+    /**
+     * Adds a widget over all others.
+     *
+     * @param widget  Widget to add on top.
+     */
+    void addOnTop(GuiWidget *widget);
+
     de::AtlasTexture &atlas();
     de::GLUniform &uAtlas();
     de::Id solidWhitePixel() const;

doomsday/client/include/ui/widgets/compositorwidget.h

@@ -0,0 +1,56 @@
+/** @file compositorwidget.h  Off-screen compositor.
+ *
+ * @authors Copyright (c) 2013 Jaakko Keränen <jaakko.keranen@iki.fi>
+ *
+ * @par License
+ * GPL: http://www.gnu.org/licenses/gpl.html
+ *
+ * <small>This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version. This program is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ * Public License for more details. You should have received a copy of the GNU
+ * General Public License along with this program; if not, see:
+ * http://www.gnu.org/licenses</small>
+ */
+
+#ifndef DENG_CLIENT_COMPOSITORWIDGET_H
+#define DENG_CLIENT_COMPOSITORWIDGET_H
+
+#include "GuiWidget"
+
+/**
+ * Off-screen compositor.
+ *
+ * All children of the compositor are drawn to an off-screen render target
+ * whose size is equal to the default render target. The default behavior of
+ * the compositor is to then draw the composited off-screen target back to the
+ * default target.
+ *
+ * @todo Allow optionally requesting more target attachments beyond the default
+ * color buffer.
+ */
+class CompositorWidget : public GuiWidget
+{
+public:
+    CompositorWidget(de::String const &name = "");
+
+    de::GLTexture &composite() const;
+
+    // Events.
+    void viewResized();
+    void preDrawChildren();
+    void postDrawChildren();
+
+protected:
+    void glInit();
+    void glDeinit();
+    void drawComposite();
+
+private:
+    DENG2_PRIVATE(d)
+};
+
+#endif // DENG_CLIENT_COMPOSITORWIDGET_H

doomsday/client/include/ui/widgets/gameuiwidget.h

@@ -29,7 +29,7 @@ class GameUIWidget : public GuiWidget
 public:
     GameUIWidget();
 
-    void draw();
+    void drawContent();
 
 private:
     DENG2_PRIVATE(d)

doomsday/client/src/ui/clientwindow.cpp

@@ -35,6 +35,7 @@
 
 #include "gl/sys_opengl.h"
 #include "gl/gl_main.h"
+#include "ui/widgets/compositorwidget.h"
 #include "ui/widgets/gamewidget.h"
 #include "ui/widgets/gameuiwidget.h"
 #include "ui/widgets/busywidget.h"
@@ -68,6 +69,7 @@ DENG2_OBSERVES(App,              GameChange)
 
     /// Root of the nomal UI widgets of this window.
     GuiRootWidget root;
+    CompositorWidget *compositor;
     GameWidget *legacy;
     GameUIWidget *gameUI;
     TaskBarWidget *taskBar;
@@ -94,6 +96,7 @@ DENG2_OBSERVES(App,              GameChange)
           needRootSizeUpdate(false),
           mode(Normal),
           root(thisPublic),
+          compositor(0),
           legacy(0),
           gameUI(0),
           taskBar(0),
@@ -127,21 +130,26 @@ DENG2_OBSERVES(App,              GameChange)
         self.canvas().audienceForKeyEvent -= this;
     }
 
+    Widget &container()
+    {
+        if(compositor)
+        {
+            return *compositor;
+        }
+        return root;
+    }
+
     void setupUI()
     {
         Style &style = ClientApp::windowSystem().style();
 
         // Background for Ring Zero.
-        background = new LabelWidget;
+        background = new LabelWidget("background");
         background->setImage(style.images().image("window.background"));
         background->setImageFit(ui::FitToSize);
         background->setSizePolicy(ui::Filled, ui::Filled);
         background->margins().set("");
-        background->rule()
-                .setInput(Rule::Left,   root.viewLeft())
-                .setInput(Rule::Top,    root.viewTop())
-                .setInput(Rule::Right,  root.viewRight())
-                .setInput(Rule::Bottom, root.viewBottom());
+        background->rule().setRect(root.viewRule());
         root.add(background);
 
         legacy = new GameWidget;
@@ -151,10 +159,16 @@ DENG2_OBSERVES(App,              GameChange)
         legacy->disable();
         root.add(legacy);
 
+        /// @todo Compositor only needed in VR modes.
+
+        compositor = new CompositorWidget;
+        compositor->rule().setRect(root.viewRule());
+        root.add(compositor);
+
         gameUI = new GameUIWidget;
         gameUI->rule().setRect(root.viewRule());
         gameUI->disable();
-        root.add(gameUI);
+        container().add(gameUI);
 
         // Game selection.
         games = new GameSelectionWidget;
@@ -164,14 +178,14 @@ DENG2_OBSERVES(App,              GameChange)
                 .setInput(Rule::Width,   OperatorRule::minimum(root.viewWidth(),
                                                                style.rules().rule("gameselection.max.width")))
                 .setAnchorPoint(Vector2f(.5f, .5f));
-        root.add(games);
+        container().add(games);
 
         // Common notification area.
         notifications = new NotificationWidget;
         notifications->rule()
                 .setInput(Rule::Top,   root.viewTop()   + style.rules().rule("gap") - notifications->shift())
                 .setInput(Rule::Right, legacy->rule().right() - style.rules().rule("gap"));
-        root.add(notifications);
+        container().add(notifications);
 
         // FPS counter for the notification area.
         fpsCounter = new LabelWidget;
@@ -184,13 +198,12 @@ DENG2_OBSERVES(App,              GameChange)
                 .setInput(Rule::Left,   root.viewLeft())
                 .setInput(Rule::Bottom, root.viewBottom() + taskBar->shift())
                 .setInput(Rule::Width,  root.viewWidth());
-        root.add(taskBar);
+        container().add(taskBar);
 
         // The game selection's height depends on the taskbar.
         games->rule().setInput(Rule::Height,
                                OperatorRule::minimum(root.viewHeight(),
-                                                     (taskBar->rule().top() - root.viewHeight() / 2) * 2,
-                                                     style.rules().rule("gameselection.max.height")));
+                                                     (taskBar->rule().top() - root.viewHeight() / 2) * 2,                                                     style.rules().rule("gameselection.max.height")));
 
         // Color adjustment dialog.
         colorAdjust = new ColorAdjustmentDialog;
@@ -393,7 +406,7 @@ DENG2_OBSERVES(App,              GameChange)
         }
 
         sidebar = widget;
-        root.insertBefore(sidebar, *notifications);
+        container().insertBefore(sidebar, *notifications);
     }
 
     void uninstallSidebar(SidebarLocation location)
@@ -408,7 +421,7 @@ DENG2_OBSERVES(App,              GameChange)
             break;
         }
 
-        root.remove(*sidebar);
+        container().remove(*sidebar);
         sidebar->deleteLater();
         sidebar = 0;
     }
@@ -541,6 +554,8 @@ void ClientWindow::canvasGLDraw(Canvas &canvas)
         d->updateRootSize();
     }
 
+    qDebug() << "ClientWindow drawing the content";
+
     d->contentXf.drawTransformed();
 
     // Finish GL drawing and swap it on to the screen. Blocks until buffers
@@ -712,6 +727,11 @@ void ClientWindow::showColorAdjustments()
     d->colorAdjust->open();
 }
 
+void ClientWindow::addOnTop(GuiWidget *widget)
+{
+    d->container().add(widget);
+}
+
 void ClientWindow::setSidebar(SidebarLocation location, GuiWidget *sidebar)
 {
     DENG2_ASSERT(location == RightEdge);

doomsday/client/src/ui/framework/guirootwidget.cpp

@@ -197,6 +197,12 @@ ClientWindow &GuiRootWidget::window()
     return *d->window;
 }
 
+void GuiRootWidget::addOnTop(GuiWidget *widget)
+{
+    // The window knows what is the correct top to add to.
+    window().addOnTop(widget);
+}
+
 AtlasTexture &GuiRootWidget::atlas()
 {
     d->initAtlas();