Merge pull request #8548 from tagcup/etc2comp

Add ETC1/ETC2 compression support though etc2comp.

1 files changed, 425 insertions, 0 deletions

diff --git a/thirdparty/etc2comp/EtcBlock4x4.cpp b/thirdparty/etc2comp/EtcBlock4x4.cpp
new file mode 100644
index 0000000000..3082fe60db
--- /dev/null
+++ b/thirdparty/etc2comp/EtcBlock4x4.cpp
@@ -0,0 +1,425 @@
+/*
+ * 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.
+ */
+
+/* 
+EtcBlock4x4.cpp
+
+Implements the state associated with each 4x4 block of pixels in an image
+
+Source images that are not a multiple of 4x4 are extended to fill the Block4x4 using pixels with an 
+alpha of NAN
+
+*/
+
+#include "EtcConfig.h"
+#include "EtcBlock4x4.h"
+
+#include "EtcBlock4x4EncodingBits.h"
+#include "EtcColor.h"
+#include "EtcImage.h"
+#include "EtcColorFloatRGBA.h"
+#include "EtcBlock4x4Encoding_RGB8.h"
+#include "EtcBlock4x4Encoding_RGBA8.h"
+#include "EtcBlock4x4Encoding_RGB8A1.h"
+#include "EtcBlock4x4Encoding_R11.h"
+#include "EtcBlock4x4Encoding_RG11.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+
+namespace Etc
+{
+	// ETC pixels are scanned vertically.  
+	// this mapping is for when someone wants to scan the ETC pixels horizontally
+	const unsigned int Block4x4::s_auiPixelOrderHScan[PIXELS] = { 0, 4, 8, 12, 1, 5, 9, 13, 2, 6, 10, 14, 3, 7, 11, 15 };
+
+	// ----------------------------------------------------------------------------------------------------
+	//
+	Block4x4::Block4x4(void)
+	{
+		m_pimageSource = nullptr;
+		m_uiSourceH = 0;
+		m_uiSourceV = 0;
+
+		m_sourcealphamix = SourceAlphaMix::UNKNOWN;
+		m_boolBorderPixels = false;
+		m_boolPunchThroughPixels = false;
+
+		m_pencoding = nullptr;
+
+		m_errormetric = ErrorMetric::NUMERIC;
+
+	}
+	Block4x4::~Block4x4()
+	{
+		m_pimageSource = nullptr;
+		if (m_pencoding)
+		{
+			delete m_pencoding;
+			m_pencoding = nullptr;
+		}
+	}
+	// ----------------------------------------------------------------------------------------------------
+	// initialization prior to encoding from a source image
+	// [a_uiSourceH,a_uiSourceV] is the location of the block in a_pimageSource
+	// a_paucEncodingBits is the place to store the final encoding
+	// a_errormetric is used for finding the best encoding
+	//
+	void Block4x4::InitFromSource(Image *a_pimageSource, 
+									unsigned int a_uiSourceH, unsigned int a_uiSourceV,
+									unsigned char *a_paucEncodingBits,
+									ErrorMetric a_errormetric)
+	{
+
+		Block4x4();
+
+		m_pimageSource = a_pimageSource;
+		m_uiSourceH = a_uiSourceH;
+		m_uiSourceV = a_uiSourceV;
+		m_errormetric = a_errormetric;
+
+		SetSourcePixels();
+
+		// set block encoder function
+		switch (m_pimageSource->GetFormat())
+		{
+		case Image::Format::ETC1:
+			m_pencoding = new Block4x4Encoding_ETC1;
+			break;
+
+		case Image::Format::RGB8:
+		case Image::Format::SRGB8:
+			m_pencoding = new Block4x4Encoding_RGB8;
+			break;
+
+		case Image::Format::RGBA8:
+		case Image::Format::SRGBA8:
+			if (a_errormetric == RGBX)
+			{
+				m_pencoding = new Block4x4Encoding_RGBA8;
+			}
+			else
+			{
+				switch (m_sourcealphamix)
+				{
+				case SourceAlphaMix::OPAQUE:
+					m_pencoding = new Block4x4Encoding_RGBA8_Opaque;
+					break;
+
+				case SourceAlphaMix::TRANSPARENT:
+					m_pencoding = new Block4x4Encoding_RGBA8_Transparent;
+					break;
+
+				case SourceAlphaMix::TRANSLUCENT:
+					m_pencoding = new Block4x4Encoding_RGBA8;
+					break;
+
+				default:
+					assert(0);
+					break;
+				}
+				break;
+			}
+			break;
+
+		case Image::Format::RGB8A1:
+		case Image::Format::SRGB8A1:
+			switch (m_sourcealphamix)
+			{
+			case SourceAlphaMix::OPAQUE:
+				m_pencoding = new Block4x4Encoding_RGB8A1_Opaque;
+				break;
+
+			case SourceAlphaMix::TRANSPARENT:
+				m_pencoding = new Block4x4Encoding_RGB8A1_Transparent;
+				break;
+
+			case SourceAlphaMix::TRANSLUCENT:
+				if (m_boolPunchThroughPixels)
+				{
+					m_pencoding = new Block4x4Encoding_RGB8A1;
+				}
+				else
+				{
+					m_pencoding = new Block4x4Encoding_RGB8A1_Opaque;
+				}
+				break;
+
+			default:
+				assert(0);
+				break;
+			}
+			break;
+
+		case Image::Format::R11:
+		case Image::Format::SIGNED_R11:
+			m_pencoding = new Block4x4Encoding_R11;
+			break;
+		case Image::Format::RG11:
+		case Image::Format::SIGNED_RG11:
+			m_pencoding = new Block4x4Encoding_RG11;
+			break;
+		default:
+			assert(0);
+			break;
+		}
+
+		m_pencoding->InitFromSource(this, m_afrgbaSource,
+									a_paucEncodingBits, a_errormetric);
+
+	}
+
+	// ----------------------------------------------------------------------------------------------------
+	// initialization of encoding state from a prior encoding using encoding bits
+	// [a_uiSourceH,a_uiSourceV] is the location of the block in a_pimageSource
+	// a_paucEncodingBits is the place to read the prior encoding
+	// a_imageformat is used to determine how to interpret a_paucEncodingBits
+	// a_errormetric was used for the prior encoding
+	//
+	void Block4x4::InitFromEtcEncodingBits(Image::Format a_imageformat,
+											unsigned int a_uiSourceH, unsigned int a_uiSourceV,
+											unsigned char *a_paucEncodingBits,
+											Image *a_pimageSource,
+											ErrorMetric a_errormetric)
+	{
+		Block4x4();
+
+		m_pimageSource = a_pimageSource;
+		m_uiSourceH = a_uiSourceH;
+		m_uiSourceV = a_uiSourceV;
+		m_errormetric = a_errormetric;
+
+		SetSourcePixels();
+
+		// set block encoder function
+		switch (a_imageformat)
+		{
+		case Image::Format::ETC1:
+			m_pencoding = new Block4x4Encoding_ETC1;
+			break;
+
+		case Image::Format::RGB8:
+		case Image::Format::SRGB8:
+			m_pencoding = new Block4x4Encoding_RGB8;
+			break;
+
+		case Image::Format::RGBA8:
+		case Image::Format::SRGBA8:
+			m_pencoding = new Block4x4Encoding_RGBA8;
+			break;
+
+		case Image::Format::RGB8A1:
+		case Image::Format::SRGB8A1:
+			m_pencoding = new Block4x4Encoding_RGB8A1;
+			break;
+
+		case Image::Format::R11:
+		case Image::Format::SIGNED_R11:
+			m_pencoding = new Block4x4Encoding_R11;
+			break;
+		case Image::Format::RG11:
+		case Image::Format::SIGNED_RG11:
+			m_pencoding = new Block4x4Encoding_RG11;
+			break;
+		default:
+			assert(0);
+			break;
+		}
+
+		m_pencoding->InitFromEncodingBits(this, a_paucEncodingBits, m_afrgbaSource,
+										m_pimageSource->GetErrorMetric());
+
+	}
+	
+	// ----------------------------------------------------------------------------------------------------
+	// set source pixels from m_pimageSource
+	// set m_alphamix
+	//
+	void Block4x4::SetSourcePixels(void)
+	{
+
+		Image::Format imageformat = m_pimageSource->GetFormat();
+
+		// alpha census
+		unsigned int uiTransparentSourcePixels = 0;
+		unsigned int uiOpaqueSourcePixels = 0;
+
+		// copy source to consecutive memory locations
+		// convert from image horizontal scan to block vertical scan
+		unsigned int uiPixel = 0;
+		for (unsigned int uiBlockPixelH = 0; uiBlockPixelH < Block4x4::COLUMNS; uiBlockPixelH++)
+		{
+			unsigned int uiSourcePixelH = m_uiSourceH + uiBlockPixelH;
+
+			for (unsigned int uiBlockPixelV = 0; uiBlockPixelV < Block4x4::ROWS; uiBlockPixelV++)
+			{
+				unsigned int uiSourcePixelV = m_uiSourceV + uiBlockPixelV;
+
+				ColorFloatRGBA *pfrgbaSource = m_pimageSource->GetSourcePixel(uiSourcePixelH, uiSourcePixelV);
+
+				// if pixel extends beyond source image because of block padding
+				if (pfrgbaSource == nullptr)
+				{
+					m_afrgbaSource[uiPixel] = ColorFloatRGBA(0.0f, 0.0f, 0.0f, NAN);	// denotes border pixel
+					m_boolBorderPixels = true;
+					uiTransparentSourcePixels++;
+				}
+				else
+				{
+					//get teh current pixel data, and store some of the attributes
+					//before capping values to fit the encoder type
+					
+					m_afrgbaSource[uiPixel] = (*pfrgbaSource).ClampRGBA();
+
+					if (m_afrgbaSource[uiPixel].fA == 1.0f || m_errormetric == RGBX)
+					{
+						m_pimageSource->m_iNumOpaquePixels++;
+					}
+					else if (m_afrgbaSource[uiPixel].fA == 0.0f)
+					{
+						m_pimageSource->m_iNumTransparentPixels++;
+					}
+					else if(m_afrgbaSource[uiPixel].fA > 0.0f && m_afrgbaSource[uiPixel].fA < 1.0f)
+					{
+						m_pimageSource->m_iNumTranslucentPixels++;
+					}
+					else
+					{
+						m_pimageSource->m_numOutOfRangeValues.fA++;
+					}
+
+					if (m_afrgbaSource[uiPixel].fR != 0.0f)
+					{
+						m_pimageSource->m_numColorValues.fR++;
+						//make sure we are getting a float between 0-1
+						if (m_afrgbaSource[uiPixel].fR - 1.0f > 0.0f)
+						{
+							m_pimageSource->m_numOutOfRangeValues.fR++;
+						}
+					}
+
+					if (m_afrgbaSource[uiPixel].fG != 0.0f)
+					{
+						m_pimageSource->m_numColorValues.fG++;
+						if (m_afrgbaSource[uiPixel].fG - 1.0f > 0.0f)
+						{
+							m_pimageSource->m_numOutOfRangeValues.fG++;
+						}
+					}
+					if (m_afrgbaSource[uiPixel].fB != 0.0f)
+					{
+						m_pimageSource->m_numColorValues.fB++;
+						if (m_afrgbaSource[uiPixel].fB - 1.0f > 0.0f)
+						{
+							m_pimageSource->m_numOutOfRangeValues.fB++;
+						}
+					}
+					// for formats with no alpha, set source alpha to 1
+					if (imageformat == Image::Format::ETC1 ||
+						imageformat == Image::Format::RGB8 ||
+						imageformat == Image::Format::SRGB8)
+					{
+						m_afrgbaSource[uiPixel].fA = 1.0f;
+					}
+
+					if (imageformat == Image::Format::R11 ||
+						imageformat == Image::Format::SIGNED_R11)
+					{
+						m_afrgbaSource[uiPixel].fA = 1.0f;
+						m_afrgbaSource[uiPixel].fG = 0.0f;
+						m_afrgbaSource[uiPixel].fB = 0.0f;
+					}
+
+					if (imageformat == Image::Format::RG11 ||
+						imageformat == Image::Format::SIGNED_RG11)
+					{
+						m_afrgbaSource[uiPixel].fA = 1.0f;
+						m_afrgbaSource[uiPixel].fB = 0.0f;
+					}
+
+				
+					// for RGB8A1, set source alpha to 0.0 or 1.0
+					// set punch through flag
+					if (imageformat == Image::Format::RGB8A1 ||
+						imageformat == Image::Format::SRGB8A1)
+					{
+						if (m_afrgbaSource[uiPixel].fA >= 0.5f)
+						{
+							m_afrgbaSource[uiPixel].fA = 1.0f;
+						}
+						else
+						{
+							m_afrgbaSource[uiPixel].fA = 0.0f;
+							m_boolPunchThroughPixels = true;
+						}
+					}
+
+					if (m_afrgbaSource[uiPixel].fA == 1.0f || m_errormetric == RGBX)
+					{
+						uiOpaqueSourcePixels++;
+					}
+					else if (m_afrgbaSource[uiPixel].fA == 0.0f)
+					{
+						uiTransparentSourcePixels++;
+					}
+
+				}
+
+				uiPixel += 1;
+			}
+		}
+
+		if (uiOpaqueSourcePixels == PIXELS)
+		{
+			m_sourcealphamix = SourceAlphaMix::OPAQUE;
+		}
+		else if (uiTransparentSourcePixels == PIXELS)
+		{
+			m_sourcealphamix = SourceAlphaMix::TRANSPARENT;
+		}
+		else
+		{
+			m_sourcealphamix = SourceAlphaMix::TRANSLUCENT;
+		}
+
+	}
+
+	// ----------------------------------------------------------------------------------------------------
+	// return a name for the encoding mode
+	//
+	const char * Block4x4::GetEncodingModeName(void)
+	{
+
+		switch (m_pencoding->GetMode())
+		{
+		case Block4x4Encoding::MODE_ETC1:
+			return "ETC1";
+		case Block4x4Encoding::MODE_T:
+			return "T";
+		case Block4x4Encoding::MODE_H:
+			return "H";
+		case Block4x4Encoding::MODE_PLANAR:
+			return "PLANAR";
+		default:
+			return "???";
+		}
+	}
+
+	// ----------------------------------------------------------------------------------------------------
+	//
+
+}