Add some external dependencies.

extern/EtcLib/EtcCodec/EtcDifferentialTrys.h

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2015 The Etc2Comp Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "EtcColorFloatRGBA.h"
+
+namespace Etc
+{
+
+	class DifferentialTrys
+	{
+	public:
+
+		static const unsigned int MAX_RADIUS = 2;
+
+		DifferentialTrys(ColorFloatRGBA a_frgbaColor1,
+							ColorFloatRGBA a_frgbaColor2,
+							const unsigned int *a_pauiPixelMapping1,
+							const unsigned int *a_pauiPixelMapping2,
+							unsigned int a_uiRadius,
+							int a_iGrayOffset1, int a_iGrayOffset2);
+
+		inline static int MoveAwayFromEdge(int a_i, int a_iDistance)
+		{
+			if (a_i < (0+ a_iDistance))
+			{
+				return (0 + a_iDistance);
+			}
+			else if (a_i > (31- a_iDistance))
+			{
+				return (31 - a_iDistance);
+			}
+
+			return a_i;
+		}
+
+		class Try
+		{
+        public :
+			static const unsigned int SELECTORS = 8;	// per half
+
+			int m_iRed;
+			int m_iGreen;
+			int m_iBlue;
+			unsigned int m_uiCW;
+			unsigned int m_auiSelectors[SELECTORS];
+			float m_fError;
+        };
+
+		class Half
+		{
+		public:
+
+			static const unsigned int MAX_TRYS = 125;
+
+			void Init(int a_iRed, int a_iGreen, int a_iBlue, 
+						const unsigned int *a_pauiPixelMapping,
+						unsigned int a_uiRadius);
+
+			// center of trys
+			int m_iRed;
+			int m_iGreen;
+			int m_iBlue;
+
+			const unsigned int *m_pauiPixelMapping;
+			unsigned int m_uiRadius;
+
+			unsigned int m_uiTrys;
+			Try m_atry[MAX_TRYS];
+
+			Try *m_ptryBest;
+		};
+
+		Half m_half1;
+		Half m_half2;
+
+		bool m_boolSeverelyBentColors;
+	};
+
+	// ----------------------------------------------------------------------------------------------------
+	//
+
+} // namespace Etc