libgui: Added ImageBank, a Bank containing Images

ImageBank serves two purposes: maps logical identifiers (represented
as Paths) to actual files in the file system, and caches the raw pixel
data in memory when needed.

doomsday/libgui/include/de/ImageBank

@@ -0,0 +1 @@
+#include "gui/imagebank.h"

doomsday/libgui/include/de/gui/imagebank.h

@@ -0,0 +1,62 @@
+/** @file imagebank.h  Bank containing Image instances loaded from files.
+ *
+ * @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 LIBGUI_IMAGEBANK_H
+#define LIBGUI_IMAGEBANK_H
+
+#include "libgui.h"
+#include "../Image"
+
+#include <de/Bank>
+
+namespace de {
+
+/**
+ * Bank containing Image instances loaded from files.
+ *
+ * @ingroup data
+ */
+class LIBGUI_PUBLIC ImageBank : public Bank
+{
+public:
+    /**
+     * Constructs a new image bank.
+     *
+     * @param flags  Properties for the bank. By default, the bank uses a
+     *               background thread because large images may take some
+     *               time to load. Hot storage is disabled because loading
+     *               images from their potentially encoded source data is
+     *               faster/more efficient than deserializating raw pixel data.
+     */
+    ImageBank(Flags const &flags = BackgroundThread | DisableHotStorage);
+
+    void add(Path const &path, String const &imageFilePath);
+
+    Image &image(Path const &path) const;
+
+protected:
+    IData *loadFromSource(ISource &source);
+    IData *newData();
+
+private:
+    DENG2_PRIVATE(d)
+};
+
+} // namespace de
+
+#endif // LIBGUI_IMAGEBANK_H

doomsday/libgui/libgui.pro

@@ -61,6 +61,7 @@ HEADERS += \
     include/de/GLUniform \
     include/de/GuiApp \
     include/de/Image \
+    include/de/ImageBank \
     include/de/KeyEvent \
     include/de/KeyEventSource \
     include/de/MouseEventSource \
@@ -85,6 +86,7 @@ HEADERS += \
     include/de/gui/gluniform.h \
     include/de/gui/guiapp.h \
     include/de/gui/image.h \
+    include/de/gui/imagebank.h \
     include/de/gui/keyevent.h \
     include/de/gui/keyeventsource.h \
     include/de/gui/libgui.h \
@@ -111,6 +113,7 @@ SOURCES +=  \
     src/gluniform.cpp \
     src/guiapp.cpp \
     src/image.cpp \
+    src/imagebank.cpp \
     src/keyevent.cpp \
     src/persistentcanvaswindow.cpp \
     src/rowatlasallocator.cpp

doomsday/libgui/src/imagebank.cpp

@@ -0,0 +1,84 @@
+/** @file imagebank.h  Bank containing Image instances loaded from files.
+ *
+ * @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>
+ */
+
+#include "de/ImageBank"
+#include "de/App"
+
+namespace de {
+
+DENG2_PIMPL_NOREF(ImageBank)
+{
+    struct ImageSource : public ISource
+    {
+        String filePath;
+
+        ImageSource(String const &path) : filePath(path)
+        {}
+
+        Time modifiedAt() const
+        {
+            return App::rootFolder().locate<File>(filePath).status().modifiedAt;
+        }
+
+        Image load() const
+        {
+            Block imageData;
+            App::rootFolder().locate<File const>(filePath) >> imageData;
+            return QImage::fromData(imageData);
+        }
+    };
+
+    struct ImageData : public IData
+    {
+        Image image;
+
+        ImageData() {}
+        ImageData(Image const &img) : image(img) {}
+
+        duint sizeInMemory() const
+        {
+            return image.byteCount();
+        }
+    };
+};
+
+ImageBank::ImageBank(Flags const &flags)
+    : Bank(flags), d(new Instance)
+{}
+
+void ImageBank::add(Path const &path, String const &imageFilePath)
+{
+    Bank::add(path, new Instance::ImageSource(imageFilePath));
+}
+
+Image &ImageBank::image(Path const &path) const
+{
+    return static_cast<Instance::ImageData &>(data(path)).image;
+}
+
+Bank::IData *ImageBank::loadFromSource(ISource &source)
+{
+    return new Instance::ImageData(static_cast<Instance::ImageSource &>(source).load());
+}
+
+Bank::IData *ImageBank::newData()
+{
+    return new Instance::ImageData();
+}
+
+} // namespace de