Gfx: Implement DWrite interfaces required for loading fonts

Common/Gfx/Util/DWriteFontCollectionLoader.cpp

@@ -0,0 +1,67 @@
+/*
+  Copyright (C) 2013 Birunthan Mohanathas
+
+  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, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#include "DWriteFontCollectionLoader.h"
+#include "DWriteFontFileEnumerator.h"
+#include <vector>
+
+namespace Gfx {
+namespace Util {
+
+DWriteFontCollectionLoader* DWriteFontCollectionLoader::GetInstance()
+{
+	static DWriteFontCollectionLoader s_Instance;
+	return &s_Instance;
+}
+
+ULONG STDMETHODCALLTYPE DWriteFontCollectionLoader::AddRef()
+{
+	// This is a singleton class so return a dummy value.
+	return 1;
+}
+
+ULONG STDMETHODCALLTYPE DWriteFontCollectionLoader::Release()
+{
+	// This is a singleton class so return a dummy value.
+	return 1;
+}
+
+HRESULT STDMETHODCALLTYPE DWriteFontCollectionLoader::QueryInterface(IID const& riid, void** ppvObject)
+{
+	if (riid == IID_IUnknown ||
+		riid == __uuidof(IDWriteFontCollectionLoader))
+	{
+		*ppvObject = this;
+		return S_OK;
+	}
+
+	*ppvObject = NULL;
+	return E_NOINTERFACE;
+}
+
+HRESULT STDMETHODCALLTYPE DWriteFontCollectionLoader::CreateEnumeratorFromKey(
+	IDWriteFactory* factory, void const* collectionKey, UINT32 collectionKeySize,
+	IDWriteFontFileEnumerator** fontFileEnumerator)
+{
+	*fontFileEnumerator = new DWriteFontFileEnumerator(
+		*(const std::vector<IDWriteFontFile*>*)collectionKey);
+	return S_OK;
+}
+
+}  // namespace Util
+}  // namespace Gfx