libappfw: Added fade-to-black utility and GuiWidgetRef smart reference

doomsday/sdk/libappfw/include/de/FadeToBlackWidget

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+#include "widgets/fadetoblackwidget.h"

doomsday/sdk/libappfw/include/de/GuiWidgetRef

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+#include "framework/guiwidgetref.h"

doomsday/sdk/libappfw/include/de/framework/guiwidgetref.h

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+/** @file guiwidgetref.h  Smart pointer to a GuiWidget.
+ *
+ * @authors Copyright (c) 2015 Jaakko Keränen <jaakko.keranen@iki.fi>
+ *
+ * @par License
+ * LGPL: http://www.gnu.org/licenses/lgpl.html
+ *
+ * <small>This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 3 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 Lesser
+ * General Public License for more details. You should have received a copy of
+ * the GNU Lesser General Public License along with this program; if not, see:
+ * http://www.gnu.org/licenses</small>
+ */
+
+#ifndef LIBAPPFW_GUIWIDGETREF_H
+#define LIBAPPFW_GUIWIDGETREF_H
+
+#include "../GuiWidget"
+
+namespace de {
+
+/**
+ * Smart pointer to a GuiWidget. Does not own the target widget.
+ */
+template <typename WidgetType>
+class GuiWidgetRef : DENG2_OBSERVES(Widget, Deletion)
+{
+public:
+    GuiWidgetRef(WidgetType *ptr = nullptr) {
+        reset(ptr);
+    }
+    ~GuiWidgetRef() {
+        reset(nullptr);
+    }
+    void reset(WidgetType *ptr) {
+        if(_ptr) _ptr->Widget::audienceForDeletion() -= this;
+        _ptr = ptr;
+        if(_ptr) _ptr->Widget::audienceForDeletion() += this;
+    }
+    WidgetType *operator -> () const {
+        return _ptr;
+    }
+    operator WidgetType const * () const {
+        return _ptr;
+    }
+    operator WidgetType * () {
+        return _ptr;
+    }
+    explicit operator bool() const {
+        return _ptr != nullptr;
+    }
+    void widgetBeingDeleted(Widget &widget) {
+        if(&widget == _ptr) {
+            _ptr = nullptr;
+        }
+    }
+
+private:
+    WidgetType *_ptr = nullptr;
+};
+
+} // namespace de
+
+#endif // LIBAPPFW_GUIWIDGETREF_H
+

doomsday/sdk/libappfw/include/de/widgets/fadetoblackwidget.h

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+/** @file fadetoblackwidget.h  Fade to/from black.
+ *
+ * @authors Copyright (c) 2015 Jaakko Keränen <jaakko.keranen@iki.fi>
+ *
+ * @par License
+ * LGPL: http://www.gnu.org/licenses/lgpl.html
+ *
+ * <small>This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 3 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 Lesser
+ * General Public License for more details. You should have received a copy of
+ * the GNU Lesser General Public License along with this program; if not, see:
+ * http://www.gnu.org/licenses</small>
+ */
+
+#ifndef LIBAPPFW_FADETOBLACKWIDGET
+#define LIBAPPFW_FADETOBLACKWIDGET
+
+#include "../LabelWidget"
+#include <de/Time>
+
+namespace de {
+
+/**
+ * Fade to/from black.
+ */
+class FadeToBlackWidget : public LabelWidget
+{
+public:
+    FadeToBlackWidget();
+
+    void initFadeFromBlack(TimeDelta const &span);
+
+    void start();
+
+    void cancel();
+
+    bool isDone() const;
+
+    void disposeIfDone();
+
+private:
+    DENG2_PRIVATE(d)
+};
+
+} // namespace de
+
+#endif // LIBAPPFW_FADETOBLACKWIDGET
+

doomsday/sdk/libappfw/src/widgets/fadetoblackwidget.cpp

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+/** @file fadetoblackwidget.cpp  Fade to/from black.
+ *
+ * @authors Copyright (c) 2015 Jaakko Keränen <jaakko.keranen@iki.fi>
+ *
+ * @par License
+ * LGPL: http://www.gnu.org/licenses/lgpl.html
+ *
+ * <small>This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 3 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 Lesser
+ * General Public License for more details. You should have received a copy of
+ * the GNU Lesser General Public License along with this program; if not, see:
+ * http://www.gnu.org/licenses</small>
+ */
+
+#include "de/FadeToBlackWidget"
+
+namespace de {
+
+DENG2_PIMPL_NOREF(FadeToBlackWidget)
+{
+    TimeDelta span = 1;
+};
+
+FadeToBlackWidget::FadeToBlackWidget() : d(new Instance)
+{
+    set(Background(Vector4f(0, 0, 0, 1)));
+}
+
+void FadeToBlackWidget::initFadeFromBlack(TimeDelta const &span)
+{
+    setOpacity(1);
+    d->span = span;
+}
+
+void FadeToBlackWidget::start()
+{
+    setOpacity(0, d->span);
+}
+
+void FadeToBlackWidget::cancel()
+{
+    setOpacity(0);
+}
+
+bool FadeToBlackWidget::isDone() const
+{
+    return opacity().done();
+}
+
+void FadeToBlackWidget::disposeIfDone()
+{
+    if(isDone())
+    {
+        destroyLater(this);
+    }
+}
+
+} // namespace de