Gfx: Implement DWrite interfaces required for loading fonts

Common/Gfx/Util/DWriteFontFileEnumerator.cpp

@@ -0,0 +1,77 @@
+/*
+  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 "DWriteFontFileEnumerator.h"
+
+namespace Gfx {
+namespace Util {
+
+DWriteFontFileEnumerator::DWriteFontFileEnumerator(const std::vector<IDWriteFontFile*>& fontFiles) :
+	m_RefCount(1),
+	m_FontFiles(fontFiles),
+	m_CurrentFontFileIndex(-1)
+{
+}
+
+ULONG STDMETHODCALLTYPE DWriteFontFileEnumerator::AddRef()
+{
+	++m_RefCount;
+	return m_RefCount;
+}
+
+ULONG STDMETHODCALLTYPE DWriteFontFileEnumerator::Release()
+{
+	--m_RefCount;
+	if (m_RefCount == 0)
+	{
+		delete this;
+		return 0;
+	}
+	return m_RefCount;
+}
+
+HRESULT STDMETHODCALLTYPE DWriteFontFileEnumerator::QueryInterface(IID const& riid, void** ppvObject)
+{
+	if (riid == IID_IUnknown ||
+		riid == __uuidof(IDWriteFontFileEnumerator))
+	{
+		*ppvObject = this;
+		AddRef();
+		return S_OK;
+	}
+
+	*ppvObject = NULL;
+	return E_NOINTERFACE;
+}
+
+HRESULT STDMETHODCALLTYPE DWriteFontFileEnumerator::MoveNext(BOOL* hasCurrentFile)
+{
+	*hasCurrentFile = (++m_CurrentFontFileIndex < m_FontFiles.size());
+	return S_OK;
+}
+
+HRESULT STDMETHODCALLTYPE DWriteFontFileEnumerator::GetCurrentFontFile(IDWriteFontFile** fontFile)
+{
+	IDWriteFontFile* currentFontFile = m_FontFiles[m_CurrentFontFileIndex];
+	currentFontFile->AddRef();
+	*fontFile = currentFontFile;
+	return S_OK;
+}
+
+}  // namespace Util
+}  // namespace Gfx