Initial commit

engines/hpl1/engine/impl/OcclusionQueryOGL.cpp

@@ -0,0 +1,84 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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 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 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/>.
+ *
+ */
+
+/*
+ * Copyright (C) 2006-2010 - Frictional Games
+ *
+ * This file is part of HPL1 Engine.
+ */
+
+#include "hpl1/engine/impl/OcclusionQueryOGL.h"
+
+#ifdef HPL1_USE_OPENGL
+
+namespace hpl {
+
+//////////////////////////////////////////////////////////////////////////
+// CONSTRUCTORS
+//////////////////////////////////////////////////////////////////////////
+
+//-----------------------------------------------------------------------
+
+cOcclusionQueryOGL::cOcclusionQueryOGL() {
+	glGenQueries(1, (GLuint *)&mlQueryId);
+	mlLastSampleCount = 0;
+}
+
+//-----------------------------------------------------------------------
+
+cOcclusionQueryOGL::~cOcclusionQueryOGL() {
+	glDeleteQueries(1, (GLuint *)&mlQueryId);
+}
+
+//-----------------------------------------------------------------------
+
+//////////////////////////////////////////////////////////////////////////
+// PUBLIC METHODS
+//////////////////////////////////////////////////////////////////////////
+
+//-----------------------------------------------------------------------
+
+void cOcclusionQueryOGL::Begin() {
+	glBeginQuery(GL_SAMPLES_PASSED, mlQueryId);
+}
+
+void cOcclusionQueryOGL::End() {
+	glEndQuery(GL_SAMPLES_PASSED);
+}
+
+bool cOcclusionQueryOGL::FetchResults() {
+	int lAvailable = 0;
+	glGetQueryObjectiv(mlQueryId, GL_QUERY_RESULT_AVAILABLE, (GLint *)&lAvailable);
+	if (lAvailable == 0)
+		return false;
+
+	glGetQueryObjectiv(mlQueryId, GL_QUERY_RESULT, (GLint *)&mlLastSampleCount);
+	return true;
+}
+
+unsigned int cOcclusionQueryOGL::GetSampleCount() {
+	return mlLastSampleCount;
+}
+
+//-----------------------------------------------------------------------
+} // namespace hpl
+
+#endif // HL1_USE_OPENGL