Add some external dependencies.

extern/EtcLib/EtcCodec/EtcBlock4x4.h

@@ -0,0 +1,172 @@
+/*
+ * 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 "EtcColor.h"
+#include "EtcColorFloatRGBA.h"
+#include "EtcErrorMetric.h"
+#include "EtcImage.h"
+#include "EtcBlock4x4Encoding.h"
+
+namespace Etc
+{
+	class Block4x4EncodingBits;
+
+	class Block4x4
+	{
+	public:
+
+		static const unsigned int ROWS = 4;
+		static const unsigned int COLUMNS = 4;
+		static const unsigned int PIXELS = ROWS * COLUMNS;
+
+		// the alpha mix for a 4x4 block of pixels
+		enum class SourceAlphaMix
+		{
+			UNKNOWN,
+			//
+			OPAQUE,			// all 1.0
+			TRANSPARENT,	// all 0.0 or NAN
+			TRANSLUCENT		// not all opaque or transparent
+		};
+
+		typedef void (Block4x4::*EncoderFunctionPtr)(void);
+
+		Block4x4(void);
+		~Block4x4();
+		void InitFromSource(Image *a_pimageSource,
+							unsigned int a_uiSourceH,
+							unsigned int a_uiSourceV,
+							unsigned char *a_paucEncodingBits,
+							ErrorMetric a_errormetric);
+
+		void InitFromEtcEncodingBits(Image::Format a_imageformat,
+										unsigned int a_uiSourceH,
+										unsigned int a_uiSourceV,
+										unsigned char *a_paucEncodingBits,
+										Image *a_pimageSource,
+										ErrorMetric a_errormetric);
+
+		// return true if final iteration was performed
+		inline void PerformEncodingIteration(float a_fEffort)
+		{
+			m_pencoding->PerformIteration(a_fEffort);
+		}
+
+		inline void SetEncodingBitsFromEncoding(void)
+		{
+			m_pencoding->SetEncodingBits();
+		}
+
+		inline unsigned int GetSourceH(void)
+		{
+			return m_uiSourceH;
+		}
+
+		inline unsigned int GetSourceV(void)
+		{
+			return m_uiSourceV;
+		}
+
+		inline float GetError(void)
+		{
+			return m_pencoding->GetError();
+		}
+
+		static const unsigned int s_auiPixelOrderHScan[PIXELS];
+
+		inline ColorFloatRGBA * GetDecodedColors(void)
+		{
+			return m_pencoding->GetDecodedColors();
+		}
+
+		inline float * GetDecodedAlphas(void)
+		{
+			return m_pencoding->GetDecodedAlphas();
+		}
+
+		inline Block4x4Encoding::Mode GetEncodingMode(void)
+		{
+			return m_pencoding->GetMode();
+		}
+
+		inline bool GetFlip(void)
+		{
+			return m_pencoding->GetFlip();
+		}
+
+		inline bool IsDifferential(void)
+		{
+			return m_pencoding->IsDifferential();
+		}
+
+		inline ColorFloatRGBA * GetSource()
+		{
+			return m_afrgbaSource;
+		}
+
+		inline ErrorMetric GetErrorMetric()
+		{
+			return m_errormetric;
+		}
+
+		const char * GetEncodingModeName(void);
+
+		inline Block4x4Encoding * GetEncoding(void)
+		{
+			return m_pencoding;
+		}
+
+		inline SourceAlphaMix GetSourceAlphaMix(void)
+		{
+			return m_sourcealphamix;
+		}
+
+		inline Image * GetImageSource(void)
+		{
+			return m_pimageSource;
+		}
+
+		inline bool HasBorderPixels(void)
+		{
+			return m_boolBorderPixels;
+		}
+
+		inline bool HasPunchThroughPixels(void)
+		{
+			return m_boolPunchThroughPixels;
+		}
+
+	private:
+
+		void SetSourcePixels(void);
+
+		Image				*m_pimageSource;
+		unsigned int		m_uiSourceH;
+		unsigned int		m_uiSourceV;
+		ErrorMetric			m_errormetric;
+		ColorFloatRGBA		m_afrgbaSource[PIXELS];		// vertical scan
+
+		SourceAlphaMix		m_sourcealphamix;
+		bool				m_boolBorderPixels;			// marked as rgba(NAN, NAN, NAN, NAN)
+		bool				m_boolPunchThroughPixels;	// RGB8A1 or SRGB8A1 with any pixels with alpha < 0.5
+
+		Block4x4Encoding	*m_pencoding;
+
+	};
+
+} // namespace Etc