milek7/sim branch opengl 3.3 renderer import

gl/query.cpp

@@ -0,0 +1,65 @@
+#include "stdafx.h"
+#include "query.h"
+#include "Globals.h"
+
+gl::query::query(targets target)
+    : target(target)
+{
+	glGenQueries(1, *this);
+}
+
+gl::query::~query()
+{
+	end();
+	glDeleteQueries(1, *this);
+}
+
+void gl::query::begin()
+{
+	if (active_queries[target])
+		active_queries[target]->end();
+
+	glBeginQuery(glenum_target(target), *this);
+	active_queries[target] = this;
+}
+
+void gl::query::end()
+{
+	if (active_queries[target] != this)
+		return;
+
+	glEndQuery(glenum_target(target));
+	active_queries[target] = nullptr;
+}
+
+std::optional<int64_t> gl::query::result()
+{
+	GLuint ready;
+	glGetQueryObjectuiv(*this, GL_QUERY_RESULT_AVAILABLE, &ready);
+	int64_t value = 0;
+	if (ready) {
+		if (!Global.gfx_usegles)
+			glGetQueryObjecti64v(*this, GL_QUERY_RESULT, &value);
+		else
+			glGetQueryObjectuiv(*this, GL_QUERY_RESULT, reinterpret_cast<GLuint*>(&value));
+
+		return std::optional<int64_t>(value);
+	}
+	return std::nullopt;
+}
+
+GLenum gl::query::glenum_target(targets target)
+{
+	static GLenum mapping[6] =
+	{
+	    GL_SAMPLES_PASSED,
+	    GL_ANY_SAMPLES_PASSED,
+	    GL_ANY_SAMPLES_PASSED_CONSERVATIVE,
+	    GL_PRIMITIVES_GENERATED,
+	    GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN,
+	    GL_TIME_ELAPSED
+	};
+	return mapping[target];
+}
+
+thread_local gl::query* gl::query::active_queries[6];