Add some external dependencies.

extern/EtcLib/EtcCodec/EtcBlock4x4Encoding.h

@@ -0,0 +1,148 @@
+/*
+ * 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"
+
+#include "EtcErrorMetric.h"
+
+#include <assert.h>
+#include <float.h>
+
+namespace Etc
+{
+	class Block4x4;
+
+	// abstract base class for specific encodings
+	class Block4x4Encoding
+	{
+	public:
+
+		static const unsigned int ROWS = 4;
+		static const unsigned int COLUMNS = 4;
+		static const unsigned int PIXELS = ROWS * COLUMNS;
+		static const float LUMA_WEIGHT;
+		static const float CHROMA_BLUE_WEIGHT;
+
+		typedef enum
+		{
+			MODE_UNKNOWN,
+			//
+			MODE_ETC1,
+			MODE_T,
+			MODE_H,
+			MODE_PLANAR,
+			MODE_R11,
+			MODE_RG11,
+			//
+			MODES
+		} Mode;
+
+		Block4x4Encoding(void);
+		//virtual ~Block4x4Encoding(void) =0;
+		virtual ~Block4x4Encoding(void) {}
+		virtual void InitFromSource(Block4x4 *a_pblockParent,
+									ColorFloatRGBA *a_pafrgbaSource,
+
+									unsigned char *a_paucEncodingBits, ErrorMetric a_errormetric) = 0;
+
+		virtual void InitFromEncodingBits(Block4x4 *a_pblockParent,
+											unsigned char *a_paucEncodingBits,
+											ColorFloatRGBA *a_pafrgbaSource,
+
+											ErrorMetric a_errormetric) = 0;
+
+		// perform an iteration of the encoding
+		// the first iteration must generate a complete, valid (if poor) encoding
+		virtual void PerformIteration(float a_fEffort) = 0;
+
+		void CalcBlockError(void);
+
+		inline float GetError(void)
+		{
+			assert(m_fError >= 0.0f);
+
+			return m_fError;
+		}
+
+		inline ColorFloatRGBA * GetDecodedColors(void)
+		{
+			return m_afrgbaDecodedColors;
+		}
+
+		inline float * GetDecodedAlphas(void)
+		{
+			return m_afDecodedAlphas;
+		}
+
+		virtual void SetEncodingBits(void) = 0;
+
+		virtual bool GetFlip(void) = 0;
+
+		virtual bool IsDifferential(void) = 0;
+
+		virtual bool HasSeverelyBentDifferentialColors(void) const = 0;
+
+		inline Mode GetMode(void)
+		{
+			return m_mode;
+		}
+
+		inline bool IsDone(void)
+		{
+			return m_boolDone;
+		}
+
+		inline void SetDoneIfPerfect()
+		{
+			if (GetError() == 0.0f)
+			{
+				m_boolDone = true;
+			}
+		}
+
+		float CalcPixelError(ColorFloatRGBA a_frgbaDecodedColor, float a_fDecodedAlpha,
+								ColorFloatRGBA a_frgbaSourcePixel);
+
+	protected:
+
+		void Init(Block4x4 *a_pblockParent,
+					ColorFloatRGBA *a_pafrgbaSource,
+
+					ErrorMetric a_errormetric);
+
+		Block4x4		*m_pblockParent;
+		ColorFloatRGBA	*m_pafrgbaSource;
+
+		bool			m_boolBorderPixels;				// if block has any border pixels
+
+		ColorFloatRGBA	m_afrgbaDecodedColors[PIXELS];	// decoded RGB components, ignore Alpha
+		float			m_afDecodedAlphas[PIXELS];		// decoded alpha component
+		float			m_fError;						// error for RGBA relative to m_pafrgbaSource
+
+		// intermediate encoding
+		Mode			m_mode;
+
+		unsigned int	m_uiEncodingIterations;
+		bool			m_boolDone;						// all iterations have been done
+		ErrorMetric		m_errormetric;
+
+	private:
+
+	};
+
+} // namespace Etc