From 16f4e083950d4e74fa24da275b4902c2b4fd376d Mon Sep 17 00:00:00 2001
From: Mark Vejvoda <mark_vejvoda@hotmail.com>
Date: Mon, 10 Jun 2013 22:38:33 +0000
Subject: [PATCH] attempt to speed up float truncation and add some unit tests

---
 .../shared_lib/include/graphics/math_util.h   | 46 +++++++++++++
 source/tests/CMakeLists.txt                   |  1 +
 .../shared_lib/graphics/math_util_test.cpp    | 68 +++++++++++++++++++
 3 files changed, 115 insertions(+)
 create mode 100644 source/tests/shared_lib/graphics/math_util_test.cpp

diff --git a/source/shared_lib/include/graphics/math_util.h b/source/shared_lib/include/graphics/math_util.h
index 6ca74d90e..59ab4476c 100644
--- a/source/shared_lib/include/graphics/math_util.h
+++ b/source/shared_lib/include/graphics/math_util.h
@@ -14,9 +14,11 @@
 
 #include "math_wrapper.h"
 #include "vec.h"
+#include "data_types.h"
 #include "leak_dumper.h"
 
 using namespace std;
+using namespace Shared::Platform;
 
 namespace Shared{ namespace Graphics{
 
@@ -276,8 +278,46 @@ inline T radToDeg(T rad){
 	return (rad*360)/(2*pi);
 }
 
+// ====================================================================================================================
+// ====================================================================================================================
+//  Inline implementation
+// ====================================================================================================================
+// ====================================================================================================================
+#if _xs_BigEndian_
+	#define _xs_iexp_				0
+	#define _xs_iman_				1
+#else
+	#define _xs_iexp_				1       //intel is little endian
+	#define _xs_iman_				0
+#endif //BigEndian_
+
+//#define finline                     __forceinline
+#define finline                     inline
+
+#ifndef _xs_DEFAULT_CONVERSION
+#define _xs_DEFAULT_CONVERSION      0
+#endif
+
+//typedef long                    int32;
+typedef double                  real64;
+const real64 _xs_doublemagic			= real64 (6755399441055744.0); 	    //2^52 * 1.5,  uses limited precisicion to floor
+
+finline int32 xs_CRoundToInt(real64 val, real64 dmr = _xs_doublemagic) {
+#if _xs_DEFAULT_CONVERSION==0
+    val		= val + dmr;
+	return ((int32*)&val)[_xs_iman_];
+    //return 0;
+#else
+    return int32(floor(val+.5));
+#endif
+}
+
+
+
 template<typename T>
 inline T truncateDecimal(const T &value, int precision=6) {
+
+/*
 	int iSigned = value >= 0 ? 1: -1;
 
 #ifdef USE_STREFLOP
@@ -288,6 +328,12 @@ inline T truncateDecimal(const T &value, int precision=6) {
 	T result = (((double)uiTemp) / pow((T)10,precision) * iSigned);
 #endif
 	return result;
+*/
+
+	T precNum = pow(10, precision);
+	T result = xs_CRoundToInt(value * precNum);
+	result /= precNum;
+	return result;
 }
 
 
diff --git a/source/tests/CMakeLists.txt b/source/tests/CMakeLists.txt
index 2ad2a988f..7ed3797a7 100644
--- a/source/tests/CMakeLists.txt
+++ b/source/tests/CMakeLists.txt
@@ -26,6 +26,7 @@ IF(BUILD_MEGAGLEST_TESTS)
 
 	SET(DIRS_WITH_SRC
                 ./
+                shared_lib/graphics
 		shared_lib/xml)
 	
 	SET(MG_INCLUDES_ROOT "./")
diff --git a/source/tests/shared_lib/graphics/math_util_test.cpp b/source/tests/shared_lib/graphics/math_util_test.cpp
new file mode 100644
index 000000000..f22dd6eeb
--- /dev/null
+++ b/source/tests/shared_lib/graphics/math_util_test.cpp
@@ -0,0 +1,68 @@
+// ==============================================================
+//	This file is part of MegaGlest Unit Tests (www.megaglest.org)
+//
+//	Copyright (C) 2013 Mark Vejvoda
+//
+//	You can redistribute this code 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
+// ==============================================================
+
+#include <cppunit/extensions/HelperMacros.h>
+#include <memory>
+#include "math_util.h"
+
+#ifdef WIN32
+#include <io.h>
+#else
+#include <unistd.h>
+#endif
+
+using namespace Shared::Graphics;
+
+//
+// Tests for XmlIo
+//
+class MathUtilTest : public CppUnit::TestFixture {
+	// Register the suite of tests for this fixture
+	CPPUNIT_TEST_SUITE( MathUtilTest );
+
+	CPPUNIT_TEST( test_RoundFloat );
+
+	CPPUNIT_TEST_SUITE_END();
+	// End of Fixture registration
+
+public:
+
+	void test_RoundFloat() {
+		float value1 = truncateDecimal<float>(1.123456f, 6);
+		CPPUNIT_ASSERT_EQUAL( 1.123456f, value1 );
+
+		value1 = truncateDecimal<float>(1.123456f, 5);
+		CPPUNIT_ASSERT_EQUAL( 1.12346f, value1 );
+
+		value1 = truncateDecimal<float>(1.123456f, 4);
+		CPPUNIT_ASSERT_EQUAL( 1.1235f, value1 );
+
+		value1 = truncateDecimal<float>(1.123456f, 3);
+		CPPUNIT_ASSERT_EQUAL( 1.123f, value1 );
+
+		value1 = truncateDecimal<float>(1.123456f, 2);
+		CPPUNIT_ASSERT_EQUAL( 1.12f, value1 );
+
+		value1 = truncateDecimal<float>(1.123456f, 1);
+		CPPUNIT_ASSERT_EQUAL( 1.1f, value1 );
+
+		int32 value2 = xs_CRoundToInt(1.123456f);
+		CPPUNIT_ASSERT_EQUAL( (int32)1, value2 );
+
+		value2 = xs_CRoundToInt(1.523456f);
+		CPPUNIT_ASSERT_EQUAL( (int32)2, value2 );
+	}
+};
+
+
+// Test Suite Registrations
+CPPUNIT_TEST_SUITE_REGISTRATION( MathUtilTest );
+//