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Diffstat (limited to 'thirdparty/etc2comp/EtcBlock4x4Encoding_ETC1.cpp')
| -rw-r--r-- | thirdparty/etc2comp/EtcBlock4x4Encoding_ETC1.cpp | 1281 |
1 files changed, 1281 insertions, 0 deletions
diff --git a/thirdparty/etc2comp/EtcBlock4x4Encoding_ETC1.cpp b/thirdparty/etc2comp/EtcBlock4x4Encoding_ETC1.cpp new file mode 100644 index 0000000000..a27f74c0d5 --- /dev/null +++ b/thirdparty/etc2comp/EtcBlock4x4Encoding_ETC1.cpp @@ -0,0 +1,1281 @@ +/* + * 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. + */ + +/* +EtcBlock4x4Encoding_ETC1.cpp + +Block4x4Encoding_ETC1 is the encoder to use when targetting file format ETC1. This encoder is also +used for the ETC1 subset of file format RGB8, RGBA8 and RGB8A1 + +*/ + +#include "EtcConfig.h" +#include "EtcBlock4x4Encoding_ETC1.h" + +#include "EtcBlock4x4.h" +#include "EtcBlock4x4EncodingBits.h" +#include "EtcDifferentialTrys.h" + +#include <stdio.h> +#include <string.h> +#include <assert.h> +#include <float.h> +#include <limits> + +namespace Etc +{ + + // pixel processing order if the flip bit = 0 (horizontal split) + const unsigned int Block4x4Encoding_ETC1::s_auiPixelOrderFlip0[PIXELS] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }; + + // pixel processing order if the flip bit = 1 (vertical split) + const unsigned int Block4x4Encoding_ETC1::s_auiPixelOrderFlip1[PIXELS] = { 0, 1, 4, 5, 8, 9, 12, 13, 2, 3, 6, 7, 10, 11, 14, 15 }; + + // pixel processing order for horizontal scan (ETC normally does a vertical scan) + const unsigned int Block4x4Encoding_ETC1::s_auiPixelOrderHScan[PIXELS] = { 0, 4, 8, 12, 1, 5, 9, 13, 2, 6, 10, 14, 3, 7, 11, 15 }; + + // pixel indices for different block halves + const unsigned int Block4x4Encoding_ETC1::s_auiLeftPixelMapping[8] = { 0, 1, 2, 3, 4, 5, 6, 7 }; + const unsigned int Block4x4Encoding_ETC1::s_auiRightPixelMapping[8] = { 8, 9, 10, 11, 12, 13, 14, 15 }; + const unsigned int Block4x4Encoding_ETC1::s_auiTopPixelMapping[8] = { 0, 1, 4, 5, 8, 9, 12, 13 }; + const unsigned int Block4x4Encoding_ETC1::s_auiBottomPixelMapping[8] = { 2, 3, 6, 7, 10, 11, 14, 15 }; + + // CW ranges that the ETC1 decoders use + // CW is basically a contrast for the different selector bits, since these values are offsets to the base color + // the first axis in the array is indexed by the CW in the encoding bits + // the second axis in the array is indexed by the selector bits + float Block4x4Encoding_ETC1::s_aafCwTable[CW_RANGES][SELECTORS] = + { + { 2.0f / 255.0f, 8.0f / 255.0f, -2.0f / 255.0f, -8.0f / 255.0f }, + { 5.0f / 255.0f, 17.0f / 255.0f, -5.0f / 255.0f, -17.0f / 255.0f }, + { 9.0f / 255.0f, 29.0f / 255.0f, -9.0f / 255.0f, -29.0f / 255.0f }, + { 13.0f / 255.0f, 42.0f / 255.0f, -13.0f / 255.0f, -42.0f / 255.0f }, + { 18.0f / 255.0f, 60.0f / 255.0f, -18.0f / 255.0f, -60.0f / 255.0f }, + { 24.0f / 255.0f, 80.0f / 255.0f, -24.0f / 255.0f, -80.0f / 255.0f }, + { 33.0f / 255.0f, 106.0f / 255.0f, -33.0f / 255.0f, -106.0f / 255.0f }, + { 47.0f / 255.0f, 183.0f / 255.0f, -47.0f / 255.0f, -183.0f / 255.0f } + }; + + // ---------------------------------------------------------------------------------------------------- + // + Block4x4Encoding_ETC1::Block4x4Encoding_ETC1(void) + { + m_mode = MODE_ETC1; + m_boolDiff = false; + m_boolFlip = false; + m_frgbaColor1 = ColorFloatRGBA(); + m_frgbaColor2 = ColorFloatRGBA(); + m_uiCW1 = 0; + m_uiCW2 = 0; + for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++) + { + m_auiSelectors[uiPixel] = 0; + m_afDecodedAlphas[uiPixel] = 1.0f; + } + + m_boolMostLikelyFlip = false; + + m_fError = -1.0f; + + m_fError1 = -1.0f; + m_fError2 = -1.0f; + m_boolSeverelyBentDifferentialColors = false; + + for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++) + { + m_afDecodedAlphas[uiPixel] = 1.0f; + } + + } + + Block4x4Encoding_ETC1::~Block4x4Encoding_ETC1(void) {} + + // ---------------------------------------------------------------------------------------------------- + // initialization prior to encoding + // a_pblockParent points to the block associated with this encoding + // a_errormetric is used to choose the best encoding + // a_pafrgbaSource points to a 4x4 block subset of the source image + // a_paucEncodingBits points to the final encoding bits + // + void Block4x4Encoding_ETC1::InitFromSource(Block4x4 *a_pblockParent, + ColorFloatRGBA *a_pafrgbaSource, + unsigned char *a_paucEncodingBits, ErrorMetric a_errormetric) + { + + Block4x4Encoding::Init(a_pblockParent, a_pafrgbaSource,a_errormetric); + + for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++) + { + m_afDecodedAlphas[uiPixel] = 1.0f; + } + + m_fError = -1.0f; + + m_pencodingbitsRGB8 = (Block4x4EncodingBits_RGB8 *)(a_paucEncodingBits); + + } + + // ---------------------------------------------------------------------------------------------------- + // initialization from the encoding bits of a previous encoding + // a_pblockParent points to the block associated with this encoding + // a_errormetric is used to choose the best encoding + // a_pafrgbaSource points to a 4x4 block subset of the source image + // a_paucEncodingBits points to the final encoding bits of a previous encoding + // + void Block4x4Encoding_ETC1::InitFromEncodingBits(Block4x4 *a_pblockParent, + unsigned char *a_paucEncodingBits, + ColorFloatRGBA *a_pafrgbaSource, + ErrorMetric a_errormetric) + { + + Block4x4Encoding::Init(a_pblockParent, a_pafrgbaSource,a_errormetric); + m_fError = -1.0f; + + m_pencodingbitsRGB8 = (Block4x4EncodingBits_RGB8 *)a_paucEncodingBits; + + m_mode = MODE_ETC1; + m_boolDiff = m_pencodingbitsRGB8->individual.diff; + m_boolFlip = m_pencodingbitsRGB8->individual.flip; + if (m_boolDiff) + { + int iR2 = (int)(m_pencodingbitsRGB8->differential.red1 + m_pencodingbitsRGB8->differential.dred2); + if (iR2 < 0) + { + iR2 = 0; + } + else if (iR2 > 31) + { + iR2 = 31; + } + + int iG2 = (int)(m_pencodingbitsRGB8->differential.green1 + m_pencodingbitsRGB8->differential.dgreen2); + if (iG2 < 0) + { + iG2 = 0; + } + else if (iG2 > 31) + { + iG2 = 31; + } + + int iB2 = (int)(m_pencodingbitsRGB8->differential.blue1 + m_pencodingbitsRGB8->differential.dblue2); + if (iB2 < 0) + { + iB2 = 0; + } + else if (iB2 > 31) + { + iB2 = 31; + } + + m_frgbaColor1 = ColorFloatRGBA::ConvertFromRGB5(m_pencodingbitsRGB8->differential.red1, m_pencodingbitsRGB8->differential.green1, m_pencodingbitsRGB8->differential.blue1); + m_frgbaColor2 = ColorFloatRGBA::ConvertFromRGB5((unsigned char)iR2, (unsigned char)iG2, (unsigned char)iB2); + + } + else + { + m_frgbaColor1 = ColorFloatRGBA::ConvertFromRGB4(m_pencodingbitsRGB8->individual.red1, m_pencodingbitsRGB8->individual.green1, m_pencodingbitsRGB8->individual.blue1); + m_frgbaColor2 = ColorFloatRGBA::ConvertFromRGB4(m_pencodingbitsRGB8->individual.red2, m_pencodingbitsRGB8->individual.green2, m_pencodingbitsRGB8->individual.blue2); + } + + m_uiCW1 = m_pencodingbitsRGB8->individual.cw1; + m_uiCW2 = m_pencodingbitsRGB8->individual.cw2; + + InitFromEncodingBits_Selectors(); + + Decode(); + + CalcBlockError(); + } + + // ---------------------------------------------------------------------------------------------------- + // init the selectors from a prior encoding + // + void Block4x4Encoding_ETC1::InitFromEncodingBits_Selectors(void) + { + + unsigned char *paucSelectors = (unsigned char *)&m_pencodingbitsRGB8->individual.selectors; + + for (unsigned int iPixel = 0; iPixel < PIXELS; iPixel++) + { + unsigned int uiByteMSB = (unsigned int)(1 - (iPixel / 8)); + unsigned int uiByteLSB = (unsigned int)(3 - (iPixel / 8)); + unsigned int uiShift = (unsigned int)(iPixel & 7); + + unsigned int uiSelectorMSB = (unsigned int)((paucSelectors[uiByteMSB] >> uiShift) & 1); + unsigned int uiSelectorLSB = (unsigned int)((paucSelectors[uiByteLSB] >> uiShift) & 1); + + m_auiSelectors[iPixel] = (uiSelectorMSB << 1) + uiSelectorLSB; + } + + } + + // ---------------------------------------------------------------------------------------------------- + // perform a single encoding iteration + // replace the encoding if a better encoding was found + // subsequent iterations generally take longer for each iteration + // set m_boolDone if encoding is perfect or encoding is finished based on a_fEffort + // + void Block4x4Encoding_ETC1::PerformIteration(float a_fEffort) + { + assert(!m_boolDone); + + switch (m_uiEncodingIterations) + { + case 0: + PerformFirstIteration(); + break; + + case 1: + TryDifferential(m_boolMostLikelyFlip, 1, 0, 0); + break; + + case 2: + TryIndividual(m_boolMostLikelyFlip, 1); + if (a_fEffort <= 49.5f) + { + m_boolDone = true; + } + break; + + case 3: + TryDifferential(!m_boolMostLikelyFlip, 1, 0, 0); + if (a_fEffort <= 59.5f) + { + m_boolDone = true; + } + break; + + case 4: + TryIndividual(!m_boolMostLikelyFlip, 1); + if (a_fEffort <= 69.5f) + { + m_boolDone = true; + } + break; + + case 5: + TryDegenerates1(); + if (a_fEffort <= 79.5f) + { + m_boolDone = true; + } + break; + + case 6: + TryDegenerates2(); + if (a_fEffort <= 89.5f) + { + m_boolDone = true; + } + break; + + case 7: + TryDegenerates3(); + if (a_fEffort <= 99.5f) + { + m_boolDone = true; + } + break; + + case 8: + TryDegenerates4(); + m_boolDone = true; + break; + + default: + assert(0); + break; + } + + m_uiEncodingIterations++; + SetDoneIfPerfect(); + } + + // ---------------------------------------------------------------------------------------------------- + // find best initial encoding to ensure block has a valid encoding + // + void Block4x4Encoding_ETC1::PerformFirstIteration(void) + { + CalculateMostLikelyFlip(); + + m_fError = FLT_MAX; + + TryDifferential(m_boolMostLikelyFlip, 0, 0, 0); + SetDoneIfPerfect(); + if (m_boolDone) + { + return; + } + + TryIndividual(m_boolMostLikelyFlip, 0); + SetDoneIfPerfect(); + if (m_boolDone) + { + return; + } + TryDifferential(!m_boolMostLikelyFlip, 0, 0, 0); + SetDoneIfPerfect(); + if (m_boolDone) + { + return; + } + TryIndividual(!m_boolMostLikelyFlip, 0); + + } + + // ---------------------------------------------------------------------------------------------------- + // algorithm: + // create a source average color for the Left, Right, Top and Bottom halves using the 8 pixels in each half + // note: the "gray line" is the line of equal delta RGB that goes thru the average color + // for each half: + // see how close each of the 8 pixels are to the "gray line" that goes thru the source average color + // create an error value that is the sum of the distances from the gray line + // h_error is the sum of Left and Right errors + // v_error is the sum of Top and Bottom errors + // + void Block4x4Encoding_ETC1::CalculateMostLikelyFlip(void) + { + static const bool DEBUG_PRINT = false; + + CalculateSourceAverages(); + + float fLeftGrayErrorSum = 0.0f; + float fRightGrayErrorSum = 0.0f; + float fTopGrayErrorSum = 0.0f; + float fBottomGrayErrorSum = 0.0f; + + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + ColorFloatRGBA *pfrgbaLeft = &m_pafrgbaSource[uiPixel]; + ColorFloatRGBA *pfrgbaRight = &m_pafrgbaSource[uiPixel + 8]; + ColorFloatRGBA *pfrgbaTop = &m_pafrgbaSource[s_auiTopPixelMapping[uiPixel]]; + ColorFloatRGBA *pfrgbaBottom = &m_pafrgbaSource[s_auiBottomPixelMapping[uiPixel]]; + + float fLeftGrayError = CalcGrayDistance2(*pfrgbaLeft, m_frgbaSourceAverageLeft); + float fRightGrayError = CalcGrayDistance2(*pfrgbaRight, m_frgbaSourceAverageRight); + float fTopGrayError = CalcGrayDistance2(*pfrgbaTop, m_frgbaSourceAverageTop); + float fBottomGrayError = CalcGrayDistance2(*pfrgbaBottom, m_frgbaSourceAverageBottom); + + fLeftGrayErrorSum += fLeftGrayError; + fRightGrayErrorSum += fRightGrayError; + fTopGrayErrorSum += fTopGrayError; + fBottomGrayErrorSum += fBottomGrayError; + } + + if (DEBUG_PRINT) + { + printf("\n%.2f %.2f\n", fLeftGrayErrorSum + fRightGrayErrorSum, fTopGrayErrorSum + fBottomGrayErrorSum); + } + + m_boolMostLikelyFlip = (fTopGrayErrorSum + fBottomGrayErrorSum) < (fLeftGrayErrorSum + fRightGrayErrorSum); + + } + + // ---------------------------------------------------------------------------------------------------- + // calculate source pixel averages for each 2x2 quadrant in a 4x4 block + // these are used to determine the averages for each of the 4 different halves (left, right, top, bottom) + // ignore pixels that have alpha == NAN (these are border pixels outside of the source image) + // weight the averages based on a pixel's alpha + // + void Block4x4Encoding_ETC1::CalculateSourceAverages(void) + { + static const bool DEBUG_PRINT = false; + + bool boolRGBX = m_pblockParent->GetImageSource()->GetErrorMetric() == ErrorMetric::RGBX; + + if (m_pblockParent->GetSourceAlphaMix() == Block4x4::SourceAlphaMix::OPAQUE || boolRGBX) + { + ColorFloatRGBA frgbaSumUL = m_pafrgbaSource[0] + m_pafrgbaSource[1] + m_pafrgbaSource[4] + m_pafrgbaSource[5]; + ColorFloatRGBA frgbaSumLL = m_pafrgbaSource[2] + m_pafrgbaSource[3] + m_pafrgbaSource[6] + m_pafrgbaSource[7]; + ColorFloatRGBA frgbaSumUR = m_pafrgbaSource[8] + m_pafrgbaSource[9] + m_pafrgbaSource[12] + m_pafrgbaSource[13]; + ColorFloatRGBA frgbaSumLR = m_pafrgbaSource[10] + m_pafrgbaSource[11] + m_pafrgbaSource[14] + m_pafrgbaSource[15]; + + m_frgbaSourceAverageLeft = (frgbaSumUL + frgbaSumLL) * 0.125f; + m_frgbaSourceAverageRight = (frgbaSumUR + frgbaSumLR) * 0.125f; + m_frgbaSourceAverageTop = (frgbaSumUL + frgbaSumUR) * 0.125f; + m_frgbaSourceAverageBottom = (frgbaSumLL + frgbaSumLR) * 0.125f; + } + else + { + float afSourceAlpha[PIXELS]; + + // treat alpha NAN as 0.0f + for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++) + { + afSourceAlpha[uiPixel] = isnan(m_pafrgbaSource[uiPixel].fA) ? + 0.0f : + m_pafrgbaSource[uiPixel].fA; + } + + ColorFloatRGBA afrgbaAlphaWeightedSource[PIXELS]; + for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++) + { + afrgbaAlphaWeightedSource[uiPixel] = m_pafrgbaSource[uiPixel] * afSourceAlpha[uiPixel]; + } + + ColorFloatRGBA frgbaSumUL = afrgbaAlphaWeightedSource[0] + + afrgbaAlphaWeightedSource[1] + + afrgbaAlphaWeightedSource[4] + + afrgbaAlphaWeightedSource[5]; + + ColorFloatRGBA frgbaSumLL = afrgbaAlphaWeightedSource[2] + + afrgbaAlphaWeightedSource[3] + + afrgbaAlphaWeightedSource[6] + + afrgbaAlphaWeightedSource[7]; + + ColorFloatRGBA frgbaSumUR = afrgbaAlphaWeightedSource[8] + + afrgbaAlphaWeightedSource[9] + + afrgbaAlphaWeightedSource[12] + + afrgbaAlphaWeightedSource[13]; + + ColorFloatRGBA frgbaSumLR = afrgbaAlphaWeightedSource[10] + + afrgbaAlphaWeightedSource[11] + + afrgbaAlphaWeightedSource[14] + + afrgbaAlphaWeightedSource[15]; + + float fWeightSumUL = afSourceAlpha[0] + + afSourceAlpha[1] + + afSourceAlpha[4] + + afSourceAlpha[5]; + + float fWeightSumLL = afSourceAlpha[2] + + afSourceAlpha[3] + + afSourceAlpha[6] + + afSourceAlpha[7]; + + float fWeightSumUR = afSourceAlpha[8] + + afSourceAlpha[9] + + afSourceAlpha[12] + + afSourceAlpha[13]; + + float fWeightSumLR = afSourceAlpha[10] + + afSourceAlpha[11] + + afSourceAlpha[14] + + afSourceAlpha[15]; + + ColorFloatRGBA frgbaSumLeft = frgbaSumUL + frgbaSumLL; + ColorFloatRGBA frgbaSumRight = frgbaSumUR + frgbaSumLR; + ColorFloatRGBA frgbaSumTop = frgbaSumUL + frgbaSumUR; + ColorFloatRGBA frgbaSumBottom = frgbaSumLL + frgbaSumLR; + + float fWeightSumLeft = fWeightSumUL + fWeightSumLL; + float fWeightSumRight = fWeightSumUR + fWeightSumLR; + float fWeightSumTop = fWeightSumUL + fWeightSumUR; + float fWeightSumBottom = fWeightSumLL + fWeightSumLR; + + // check to see if there is at least 1 pixel with non-zero alpha + // completely transparent block should not make it to this code + assert((fWeightSumLeft + fWeightSumRight) > 0.0f); + assert((fWeightSumTop + fWeightSumBottom) > 0.0f); + + if (fWeightSumLeft > 0.0f) + { + m_frgbaSourceAverageLeft = frgbaSumLeft * (1.0f/fWeightSumLeft); + } + if (fWeightSumRight > 0.0f) + { + m_frgbaSourceAverageRight = frgbaSumRight * (1.0f/fWeightSumRight); + } + if (fWeightSumTop > 0.0f) + { + m_frgbaSourceAverageTop = frgbaSumTop * (1.0f/fWeightSumTop); + } + if (fWeightSumBottom > 0.0f) + { + m_frgbaSourceAverageBottom = frgbaSumBottom * (1.0f/fWeightSumBottom); + } + + if (fWeightSumLeft == 0.0f) + { + assert(fWeightSumRight > 0.0f); + m_frgbaSourceAverageLeft = m_frgbaSourceAverageRight; + } + if (fWeightSumRight == 0.0f) + { + assert(fWeightSumLeft > 0.0f); + m_frgbaSourceAverageRight = m_frgbaSourceAverageLeft; + } + if (fWeightSumTop == 0.0f) + { + assert(fWeightSumBottom > 0.0f); + m_frgbaSourceAverageTop = m_frgbaSourceAverageBottom; + } + if (fWeightSumBottom == 0.0f) + { + assert(fWeightSumTop > 0.0f); + m_frgbaSourceAverageBottom = m_frgbaSourceAverageTop; + } + } + + + + if (DEBUG_PRINT) + { + printf("\ntarget: [%.2f,%.2f,%.2f] [%.2f,%.2f,%.2f] [%.2f,%.2f,%.2f] [%.2f,%.2f,%.2f]\n", + m_frgbaSourceAverageLeft.fR, m_frgbaSourceAverageLeft.fG, m_frgbaSourceAverageLeft.fB, + m_frgbaSourceAverageRight.fR, m_frgbaSourceAverageRight.fG, m_frgbaSourceAverageRight.fB, + m_frgbaSourceAverageTop.fR, m_frgbaSourceAverageTop.fG, m_frgbaSourceAverageTop.fB, + m_frgbaSourceAverageBottom.fR, m_frgbaSourceAverageBottom.fG, m_frgbaSourceAverageBottom.fB); + } + + } + + // ---------------------------------------------------------------------------------------------------- + // try an ETC1 differential mode encoding + // use a_boolFlip to set the encoding F bit + // use a_uiRadius to alter basecolor components in the range[-a_uiRadius:a_uiRadius] + // use a_iGrayOffset1 and a_iGrayOffset2 to offset the basecolor to search for degenerate encodings + // replace the encoding if the encoding error is less than previous encoding + // + void Block4x4Encoding_ETC1::TryDifferential(bool a_boolFlip, unsigned int a_uiRadius, + int a_iGrayOffset1, int a_iGrayOffset2) + { + + ColorFloatRGBA frgbaColor1; + ColorFloatRGBA frgbaColor2; + + const unsigned int *pauiPixelMapping1; + const unsigned int *pauiPixelMapping2; + + if (a_boolFlip) + { + frgbaColor1 = m_frgbaSourceAverageTop; + frgbaColor2 = m_frgbaSourceAverageBottom; + + pauiPixelMapping1 = s_auiTopPixelMapping; + pauiPixelMapping2 = s_auiBottomPixelMapping; + } + else + { + frgbaColor1 = m_frgbaSourceAverageLeft; + frgbaColor2 = m_frgbaSourceAverageRight; + + pauiPixelMapping1 = s_auiLeftPixelMapping; + pauiPixelMapping2 = s_auiRightPixelMapping; + } + + DifferentialTrys trys(frgbaColor1, frgbaColor2, pauiPixelMapping1, pauiPixelMapping2, + a_uiRadius, a_iGrayOffset1, a_iGrayOffset2); + + Block4x4Encoding_ETC1 encodingTry = *this; + encodingTry.m_boolFlip = a_boolFlip; + + encodingTry.TryDifferentialHalf(&trys.m_half1); + encodingTry.TryDifferentialHalf(&trys.m_half2); + + // find best halves that are within differential range + DifferentialTrys::Try *ptryBest1 = nullptr; + DifferentialTrys::Try *ptryBest2 = nullptr; + encodingTry.m_fError = FLT_MAX; + + // see if the best of each half are in differential range + int iDRed = trys.m_half2.m_ptryBest->m_iRed - trys.m_half1.m_ptryBest->m_iRed; + int iDGreen = trys.m_half2.m_ptryBest->m_iGreen - trys.m_half1.m_ptryBest->m_iGreen; + int iDBlue = trys.m_half2.m_ptryBest->m_iBlue - trys.m_half1.m_ptryBest->m_iBlue; + if (iDRed >= -4 && iDRed <= 3 && iDGreen >= -4 && iDGreen <= 3 && iDBlue >= -4 && iDBlue <= 3) + { + ptryBest1 = trys.m_half1.m_ptryBest; + ptryBest2 = trys.m_half2.m_ptryBest; + encodingTry.m_fError = trys.m_half1.m_ptryBest->m_fError + trys.m_half2.m_ptryBest->m_fError; + } + else + { + // else, find the next best halves that are in differential range + for (DifferentialTrys::Try *ptry1 = &trys.m_half1.m_atry[0]; + ptry1 < &trys.m_half1.m_atry[trys.m_half1.m_uiTrys]; + ptry1++) + { + for (DifferentialTrys::Try *ptry2 = &trys.m_half2.m_atry[0]; + ptry2 < &trys.m_half2.m_atry[trys.m_half2.m_uiTrys]; + ptry2++) + { + iDRed = ptry2->m_iRed - ptry1->m_iRed; + bool boolValidRedDelta = iDRed <= 3 && iDRed >= -4; + iDGreen = ptry2->m_iGreen - ptry1->m_iGreen; + bool boolValidGreenDelta = iDGreen <= 3 && iDGreen >= -4; + iDBlue = ptry2->m_iBlue - ptry1->m_iBlue; + bool boolValidBlueDelta = iDBlue <= 3 && iDBlue >= -4; + + if (boolValidRedDelta && boolValidGreenDelta && boolValidBlueDelta) + { + float fError = ptry1->m_fError + ptry2->m_fError; + + if (fError < encodingTry.m_fError) + { + encodingTry.m_fError = fError; + + ptryBest1 = ptry1; + ptryBest2 = ptry2; + } + } + + } + } + assert(encodingTry.m_fError < FLT_MAX); + assert(ptryBest1 != nullptr); + assert(ptryBest2 != nullptr); + } + + if (encodingTry.m_fError < m_fError) + { + m_mode = MODE_ETC1; + m_boolDiff = true; + m_boolFlip = encodingTry.m_boolFlip; + m_frgbaColor1 = ColorFloatRGBA::ConvertFromRGB5((unsigned char)ptryBest1->m_iRed, (unsigned char)ptryBest1->m_iGreen, (unsigned char)ptryBest1->m_iBlue); + m_frgbaColor2 = ColorFloatRGBA::ConvertFromRGB5((unsigned char)ptryBest2->m_iRed, (unsigned char)ptryBest2->m_iGreen, (unsigned char)ptryBest2->m_iBlue); + m_uiCW1 = ptryBest1->m_uiCW; + m_uiCW2 = ptryBest2->m_uiCW; + + for (unsigned int uiPixelOrder = 0; uiPixelOrder < PIXELS / 2; uiPixelOrder++) + { + unsigned int uiPixel1 = pauiPixelMapping1[uiPixelOrder]; + unsigned int uiPixel2 = pauiPixelMapping2[uiPixelOrder]; + + unsigned int uiSelector1 = ptryBest1->m_auiSelectors[uiPixelOrder]; + unsigned int uiSelector2 = ptryBest2->m_auiSelectors[uiPixelOrder]; + + m_auiSelectors[uiPixel1] = uiSelector1; + m_auiSelectors[uiPixel2] = ptryBest2->m_auiSelectors[uiPixelOrder]; + + float fDeltaRGB1 = s_aafCwTable[m_uiCW1][uiSelector1]; + float fDeltaRGB2 = s_aafCwTable[m_uiCW2][uiSelector2]; + + m_afrgbaDecodedColors[uiPixel1] = (m_frgbaColor1 + fDeltaRGB1).ClampRGB(); + m_afrgbaDecodedColors[uiPixel2] = (m_frgbaColor2 + fDeltaRGB2).ClampRGB(); + } + + m_fError1 = ptryBest1->m_fError; + m_fError2 = ptryBest2->m_fError; + m_boolSeverelyBentDifferentialColors = trys.m_boolSeverelyBentColors; + m_fError = m_fError1 + m_fError2; + + // sanity check + { + int iRed1 = m_frgbaColor1.IntRed(31.0f); + int iGreen1 = m_frgbaColor1.IntGreen(31.0f); + int iBlue1 = m_frgbaColor1.IntBlue(31.0f); + + int iRed2 = m_frgbaColor2.IntRed(31.0f); + int iGreen2 = m_frgbaColor2.IntGreen(31.0f); + int iBlue2 = m_frgbaColor2.IntBlue(31.0f); + + iDRed = iRed2 - iRed1; + iDGreen = iGreen2 - iGreen1; + iDBlue = iBlue2 - iBlue1; + + assert(iDRed >= -4 && iDRed < 4); + assert(iDGreen >= -4 && iDGreen < 4); + assert(iDBlue >= -4 && iDBlue < 4); + } + } + + } + + // ---------------------------------------------------------------------------------------------------- + // try an ETC1 differential mode encoding for a half of a 4x4 block + // vary the basecolor components using a radius + // + void Block4x4Encoding_ETC1::TryDifferentialHalf(DifferentialTrys::Half *a_phalf) + { + + a_phalf->m_ptryBest = nullptr; + float fBestTryError = FLT_MAX; + + a_phalf->m_uiTrys = 0; + for (int iRed = a_phalf->m_iRed - (int)a_phalf->m_uiRadius; + iRed <= a_phalf->m_iRed + (int)a_phalf->m_uiRadius; + iRed++) + { + assert(iRed >= 0 && iRed <= 31); + + for (int iGreen = a_phalf->m_iGreen - (int)a_phalf->m_uiRadius; + iGreen <= a_phalf->m_iGreen + (int)a_phalf->m_uiRadius; + iGreen++) + { + assert(iGreen >= 0 && iGreen <= 31); + + for (int iBlue = a_phalf->m_iBlue - (int)a_phalf->m_uiRadius; + iBlue <= a_phalf->m_iBlue + (int)a_phalf->m_uiRadius; + iBlue++) + { + assert(iBlue >= 0 && iBlue <= 31); + + DifferentialTrys::Try *ptry = &a_phalf->m_atry[a_phalf->m_uiTrys]; + assert(ptry < &a_phalf->m_atry[DifferentialTrys::Half::MAX_TRYS]); + + ptry->m_iRed = iRed; + ptry->m_iGreen = iGreen; + ptry->m_iBlue = iBlue; + ptry->m_fError = FLT_MAX; + ColorFloatRGBA frgbaColor = ColorFloatRGBA::ConvertFromRGB5((unsigned char)iRed, (unsigned char)iGreen, (unsigned char)iBlue); + + // try each CW + for (unsigned int uiCW = 0; uiCW < CW_RANGES; uiCW++) + { + unsigned int auiPixelSelectors[PIXELS / 2]; + ColorFloatRGBA afrgbaDecodedPixels[PIXELS / 2]; + float afPixelErrors[PIXELS / 2] = { FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX, + FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX }; + + // pre-compute decoded pixels for each selector + ColorFloatRGBA afrgbaSelectors[SELECTORS]; + assert(SELECTORS == 4); + afrgbaSelectors[0] = (frgbaColor + s_aafCwTable[uiCW][0]).ClampRGB(); + afrgbaSelectors[1] = (frgbaColor + s_aafCwTable[uiCW][1]).ClampRGB(); + afrgbaSelectors[2] = (frgbaColor + s_aafCwTable[uiCW][2]).ClampRGB(); + afrgbaSelectors[3] = (frgbaColor + s_aafCwTable[uiCW][3]).ClampRGB(); + + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + ColorFloatRGBA *pfrgbaSourcePixel = &m_pafrgbaSource[a_phalf->m_pauiPixelMapping[uiPixel]]; + ColorFloatRGBA frgbaDecodedPixel; + + for (unsigned int uiSelector = 0; uiSelector < SELECTORS; uiSelector++) + { + frgbaDecodedPixel = afrgbaSelectors[uiSelector]; + + float fPixelError; + + fPixelError = CalcPixelError(frgbaDecodedPixel, m_afDecodedAlphas[a_phalf->m_pauiPixelMapping[uiPixel]], + *pfrgbaSourcePixel); + + if (fPixelError < afPixelErrors[uiPixel]) + { + auiPixelSelectors[uiPixel] = uiSelector; + afrgbaDecodedPixels[uiPixel] = frgbaDecodedPixel; + afPixelErrors[uiPixel] = fPixelError; + } + + } + } + + // add up all pixel errors + float fCWError = 0.0f; + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + fCWError += afPixelErrors[uiPixel]; + } + + // if best CW so far + if (fCWError < ptry->m_fError) + { + ptry->m_uiCW = uiCW; + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + ptry->m_auiSelectors[uiPixel] = auiPixelSelectors[uiPixel]; + } + ptry->m_fError = fCWError; + } + + } + + if (ptry->m_fError < fBestTryError) + { + a_phalf->m_ptryBest = ptry; + fBestTryError = ptry->m_fError; + } + + assert(ptry->m_fError < FLT_MAX); + + a_phalf->m_uiTrys++; + } + } + } + + } + + // ---------------------------------------------------------------------------------------------------- + // try an ETC1 individual mode encoding + // use a_boolFlip to set the encoding F bit + // use a_uiRadius to alter basecolor components in the range[-a_uiRadius:a_uiRadius] + // replace the encoding if the encoding error is less than previous encoding + // + void Block4x4Encoding_ETC1::TryIndividual(bool a_boolFlip, unsigned int a_uiRadius) + { + + ColorFloatRGBA frgbaColor1; + ColorFloatRGBA frgbaColor2; + + const unsigned int *pauiPixelMapping1; + const unsigned int *pauiPixelMapping2; + + if (a_boolFlip) + { + frgbaColor1 = m_frgbaSourceAverageTop; + frgbaColor2 = m_frgbaSourceAverageBottom; + + pauiPixelMapping1 = s_auiTopPixelMapping; + pauiPixelMapping2 = s_auiBottomPixelMapping; + } + else + { + frgbaColor1 = m_frgbaSourceAverageLeft; + frgbaColor2 = m_frgbaSourceAverageRight; + + pauiPixelMapping1 = s_auiLeftPixelMapping; + pauiPixelMapping2 = s_auiRightPixelMapping; + } + + IndividualTrys trys(frgbaColor1, frgbaColor2, pauiPixelMapping1, pauiPixelMapping2, a_uiRadius); + + Block4x4Encoding_ETC1 encodingTry = *this; + encodingTry.m_boolFlip = a_boolFlip; + + encodingTry.TryIndividualHalf(&trys.m_half1); + encodingTry.TryIndividualHalf(&trys.m_half2); + + // use the best of each half + IndividualTrys::Try *ptryBest1 = trys.m_half1.m_ptryBest; + IndividualTrys::Try *ptryBest2 = trys.m_half2.m_ptryBest; + encodingTry.m_fError = trys.m_half1.m_ptryBest->m_fError + trys.m_half2.m_ptryBest->m_fError; + + if (encodingTry.m_fError < m_fError) + { + m_mode = MODE_ETC1; + m_boolDiff = false; + m_boolFlip = encodingTry.m_boolFlip; + m_frgbaColor1 = ColorFloatRGBA::ConvertFromRGB4((unsigned char)ptryBest1->m_iRed, (unsigned char)ptryBest1->m_iGreen, (unsigned char)ptryBest1->m_iBlue); + m_frgbaColor2 = ColorFloatRGBA::ConvertFromRGB4((unsigned char)ptryBest2->m_iRed, (unsigned char)ptryBest2->m_iGreen, (unsigned char)ptryBest2->m_iBlue); + m_uiCW1 = ptryBest1->m_uiCW; + m_uiCW2 = ptryBest2->m_uiCW; + + for (unsigned int uiPixelOrder = 0; uiPixelOrder < PIXELS / 2; uiPixelOrder++) + { + unsigned int uiPixel1 = pauiPixelMapping1[uiPixelOrder]; + unsigned int uiPixel2 = pauiPixelMapping2[uiPixelOrder]; + + unsigned int uiSelector1 = ptryBest1->m_auiSelectors[uiPixelOrder]; + unsigned int uiSelector2 = ptryBest2->m_auiSelectors[uiPixelOrder]; + + m_auiSelectors[uiPixel1] = uiSelector1; + m_auiSelectors[uiPixel2] = ptryBest2->m_auiSelectors[uiPixelOrder]; + + float fDeltaRGB1 = s_aafCwTable[m_uiCW1][uiSelector1]; + float fDeltaRGB2 = s_aafCwTable[m_uiCW2][uiSelector2]; + + m_afrgbaDecodedColors[uiPixel1] = (m_frgbaColor1 + fDeltaRGB1).ClampRGB(); + m_afrgbaDecodedColors[uiPixel2] = (m_frgbaColor2 + fDeltaRGB2).ClampRGB(); + } + + m_fError1 = ptryBest1->m_fError; + m_fError2 = ptryBest2->m_fError; + m_fError = m_fError1 + m_fError2; + } + + } + + // ---------------------------------------------------------------------------------------------------- + // try an ETC1 differential mode encoding for a half of a 4x4 block + // vary the basecolor components using a radius + // + void Block4x4Encoding_ETC1::TryIndividualHalf(IndividualTrys::Half *a_phalf) + { + + a_phalf->m_ptryBest = nullptr; + float fBestTryError = FLT_MAX; + + a_phalf->m_uiTrys = 0; + for (int iRed = a_phalf->m_iRed - (int)a_phalf->m_uiRadius; + iRed <= a_phalf->m_iRed + (int)a_phalf->m_uiRadius; + iRed++) + { + assert(iRed >= 0 && iRed <= 15); + + for (int iGreen = a_phalf->m_iGreen - (int)a_phalf->m_uiRadius; + iGreen <= a_phalf->m_iGreen + (int)a_phalf->m_uiRadius; + iGreen++) + { + assert(iGreen >= 0 && iGreen <= 15); + + for (int iBlue = a_phalf->m_iBlue - (int)a_phalf->m_uiRadius; + iBlue <= a_phalf->m_iBlue + (int)a_phalf->m_uiRadius; + iBlue++) + { + assert(iBlue >= 0 && iBlue <= 15); + + IndividualTrys::Try *ptry = &a_phalf->m_atry[a_phalf->m_uiTrys]; + assert(ptry < &a_phalf->m_atry[IndividualTrys::Half::MAX_TRYS]); + + ptry->m_iRed = iRed; + ptry->m_iGreen = iGreen; + ptry->m_iBlue = iBlue; + ptry->m_fError = FLT_MAX; + ColorFloatRGBA frgbaColor = ColorFloatRGBA::ConvertFromRGB4((unsigned char)iRed, (unsigned char)iGreen, (unsigned char)iBlue); + + // try each CW + for (unsigned int uiCW = 0; uiCW < CW_RANGES; uiCW++) + { + unsigned int auiPixelSelectors[PIXELS / 2]; + ColorFloatRGBA afrgbaDecodedPixels[PIXELS / 2]; + float afPixelErrors[PIXELS / 2] = { FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX, + FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX }; + + // pre-compute decoded pixels for each selector + ColorFloatRGBA afrgbaSelectors[SELECTORS]; + assert(SELECTORS == 4); + afrgbaSelectors[0] = (frgbaColor + s_aafCwTable[uiCW][0]).ClampRGB(); + afrgbaSelectors[1] = (frgbaColor + s_aafCwTable[uiCW][1]).ClampRGB(); + afrgbaSelectors[2] = (frgbaColor + s_aafCwTable[uiCW][2]).ClampRGB(); + afrgbaSelectors[3] = (frgbaColor + s_aafCwTable[uiCW][3]).ClampRGB(); + + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + ColorFloatRGBA *pfrgbaSourcePixel = &m_pafrgbaSource[a_phalf->m_pauiPixelMapping[uiPixel]]; + ColorFloatRGBA frgbaDecodedPixel; + + for (unsigned int uiSelector = 0; uiSelector < SELECTORS; uiSelector++) + { + frgbaDecodedPixel = afrgbaSelectors[uiSelector]; + + float fPixelError; + + fPixelError = CalcPixelError(frgbaDecodedPixel, m_afDecodedAlphas[a_phalf->m_pauiPixelMapping[uiPixel]], + *pfrgbaSourcePixel); + + if (fPixelError < afPixelErrors[uiPixel]) + { + auiPixelSelectors[uiPixel] = uiSelector; + afrgbaDecodedPixels[uiPixel] = frgbaDecodedPixel; + afPixelErrors[uiPixel] = fPixelError; + } + + } + } + + // add up all pixel errors + float fCWError = 0.0f; + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + fCWError += afPixelErrors[uiPixel]; + } + + // if best CW so far + if (fCWError < ptry->m_fError) + { + ptry->m_uiCW = uiCW; + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + ptry->m_auiSelectors[uiPixel] = auiPixelSelectors[uiPixel]; + } + ptry->m_fError = fCWError; + } + + } + + if (ptry->m_fError < fBestTryError) + { + a_phalf->m_ptryBest = ptry; + fBestTryError = ptry->m_fError; + } + + assert(ptry->m_fError < FLT_MAX); + + a_phalf->m_uiTrys++; + } + } + } + + } + + // ---------------------------------------------------------------------------------------------------- + // try version 1 of the degenerate search + // degenerate encodings use basecolor movement and a subset of the selectors to find useful encodings + // each subsequent version of the degenerate search uses more basecolor movement and is less likely to + // be successfull + // + void Block4x4Encoding_ETC1::TryDegenerates1(void) + { + + TryDifferential(m_boolMostLikelyFlip, 1, -2, 0); + TryDifferential(m_boolMostLikelyFlip, 1, 2, 0); + TryDifferential(m_boolMostLikelyFlip, 1, 0, 2); + TryDifferential(m_boolMostLikelyFlip, 1, 0, -2); + + } + + // ---------------------------------------------------------------------------------------------------- + // try version 2 of the degenerate search + // degenerate encodings use basecolor movement and a subset of the selectors to find useful encodings + // each subsequent version of the degenerate search uses more basecolor movement and is less likely to + // be successfull + // + void Block4x4Encoding_ETC1::TryDegenerates2(void) + { + + TryDifferential(!m_boolMostLikelyFlip, 1, -2, 0); + TryDifferential(!m_boolMostLikelyFlip, 1, 2, 0); + TryDifferential(!m_boolMostLikelyFlip, 1, 0, 2); + TryDifferential(!m_boolMostLikelyFlip, 1, 0, -2); + + } + + // ---------------------------------------------------------------------------------------------------- + // try version 3 of the degenerate search + // degenerate encodings use basecolor movement and a subset of the selectors to find useful encodings + // each subsequent version of the degenerate search uses more basecolor movement and is less likely to + // be successfull + // + void Block4x4Encoding_ETC1::TryDegenerates3(void) + { + + TryDifferential(m_boolMostLikelyFlip, 1, -2, -2); + TryDifferential(m_boolMostLikelyFlip, 1, -2, 2); + TryDifferential(m_boolMostLikelyFlip, 1, 2, -2); + TryDifferential(m_boolMostLikelyFlip, 1, 2, 2); + + } + + // ---------------------------------------------------------------------------------------------------- + // try version 4 of the degenerate search + // degenerate encodings use basecolor movement and a subset of the selectors to find useful encodings + // each subsequent version of the degenerate search uses more basecolor movement and is less likely to + // be successfull + // + void Block4x4Encoding_ETC1::TryDegenerates4(void) + { + + TryDifferential(m_boolMostLikelyFlip, 1, -4, 0); + TryDifferential(m_boolMostLikelyFlip, 1, 4, 0); + TryDifferential(m_boolMostLikelyFlip, 1, 0, 4); + TryDifferential(m_boolMostLikelyFlip, 1, 0, -4); + + } + + // ---------------------------------------------------------------------------------------------------- + // find the best selector for each pixel based on a particular basecolor and CW that have been previously set + // calculate the selectors for each half of the block separately + // set the block error as the sum of each half's error + // + void Block4x4Encoding_ETC1::CalculateSelectors() + { + if (m_boolFlip) + { + CalculateHalfOfTheSelectors(0, s_auiTopPixelMapping); + CalculateHalfOfTheSelectors(1, s_auiBottomPixelMapping); + } + else + { + CalculateHalfOfTheSelectors(0, s_auiLeftPixelMapping); + CalculateHalfOfTheSelectors(1, s_auiRightPixelMapping); + } + + m_fError = m_fError1 + m_fError2; + } + + // ---------------------------------------------------------------------------------------------------- + // choose best selectors for half of the block + // calculate the error for half of the block + // + void Block4x4Encoding_ETC1::CalculateHalfOfTheSelectors(unsigned int a_uiHalf, + const unsigned int *pauiPixelMapping) + { + static const bool DEBUG_PRINT = false; + + ColorFloatRGBA *pfrgbaColor = a_uiHalf ? &m_frgbaColor2 : &m_frgbaColor1; + unsigned int *puiCW = a_uiHalf ? &m_uiCW2 : &m_uiCW1; + + float *pfHalfError = a_uiHalf ? &m_fError2 : &m_fError1; + *pfHalfError = FLT_MAX; + + // try each CW + for (unsigned int uiCW = 0; uiCW < CW_RANGES; uiCW++) + { + if (DEBUG_PRINT) + { + printf("\ncw=%u\n", uiCW); + } + + unsigned int auiPixelSelectors[PIXELS / 2]; + ColorFloatRGBA afrgbaDecodedPixels[PIXELS / 2]; + float afPixelErrors[PIXELS / 2] = { FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX, FLT_MAX }; + + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + if (DEBUG_PRINT) + { + printf("\tsource [%.2f,%.2f,%.2f]\n", m_pafrgbaSource[pauiPixelMapping[uiPixel]].fR, + m_pafrgbaSource[pauiPixelMapping[uiPixel]].fG, m_pafrgbaSource[pauiPixelMapping[uiPixel]].fB); + } + + ColorFloatRGBA *pfrgbaSourcePixel = &m_pafrgbaSource[pauiPixelMapping[uiPixel]]; + ColorFloatRGBA frgbaDecodedPixel; + + for (unsigned int uiSelector = 0; uiSelector < SELECTORS; uiSelector++) + { + float fDeltaRGB = s_aafCwTable[uiCW][uiSelector]; + + frgbaDecodedPixel = (*pfrgbaColor + fDeltaRGB).ClampRGB(); + + float fPixelError; + + fPixelError = CalcPixelError(frgbaDecodedPixel, m_afDecodedAlphas[pauiPixelMapping[uiPixel]], + *pfrgbaSourcePixel); + + if (DEBUG_PRINT) + { + printf("\tpixel %u, index %u [%.2f,%.2f,%.2f], error %.2f", uiPixel, uiSelector, + frgbaDecodedPixel.fR, + frgbaDecodedPixel.fG, + frgbaDecodedPixel.fB, + fPixelError); + } + + if (fPixelError < afPixelErrors[uiPixel]) + { + if (DEBUG_PRINT) + { + printf(" *"); + } + + auiPixelSelectors[uiPixel] = uiSelector; + afrgbaDecodedPixels[uiPixel] = frgbaDecodedPixel; + afPixelErrors[uiPixel] = fPixelError; + } + + if (DEBUG_PRINT) + { + printf("\n"); + } + } + } + + // add up all pixel errors + float fCWError = 0.0f; + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + fCWError += afPixelErrors[uiPixel]; + } + if (DEBUG_PRINT) + { + printf("\terror %.2f\n", fCWError); + } + + // if best CW so far + if (fCWError < *pfHalfError) + { + *pfHalfError = fCWError; + *puiCW = uiCW; + for (unsigned int uiPixel = 0; uiPixel < 8; uiPixel++) + { + m_auiSelectors[pauiPixelMapping[uiPixel]] = auiPixelSelectors[uiPixel]; + m_afrgbaDecodedColors[pauiPixelMapping[uiPixel]] = afrgbaDecodedPixels[uiPixel]; + } + } + } + + } + + // ---------------------------------------------------------------------------------------------------- + // set the encoding bits based on encoding state + // + void Block4x4Encoding_ETC1::SetEncodingBits(void) + { + assert(m_mode == MODE_ETC1); + + if (m_boolDiff) + { + int iRed1 = m_frgbaColor1.IntRed(31.0f); + int iGreen1 = m_frgbaColor1.IntGreen(31.0f); + int iBlue1 = m_frgbaColor1.IntBlue(31.0f); + + int iRed2 = m_frgbaColor2.IntRed(31.0f); + int iGreen2 = m_frgbaColor2.IntGreen(31.0f); + int iBlue2 = m_frgbaColor2.IntBlue(31.0f); + + int iDRed2 = iRed2 - iRed1; + int iDGreen2 = iGreen2 - iGreen1; + int iDBlue2 = iBlue2 - iBlue1; + + assert(iDRed2 >= -4 && iDRed2 < 4); + assert(iDGreen2 >= -4 && iDGreen2 < 4); + assert(iDBlue2 >= -4 && iDBlue2 < 4); + + m_pencodingbitsRGB8->differential.red1 = (unsigned int)iRed1; + m_pencodingbitsRGB8->differential.green1 = (unsigned int)iGreen1; + m_pencodingbitsRGB8->differential.blue1 = (unsigned int)iBlue1; + + m_pencodingbitsRGB8->differential.dred2 = iDRed2; + m_pencodingbitsRGB8->differential.dgreen2 = iDGreen2; + m_pencodingbitsRGB8->differential.dblue2 = iDBlue2; + } + else + { + m_pencodingbitsRGB8->individual.red1 = (unsigned int)m_frgbaColor1.IntRed(15.0f); + m_pencodingbitsRGB8->individual.green1 = (unsigned int)m_frgbaColor1.IntGreen(15.0f); + m_pencodingbitsRGB8->individual.blue1 = (unsigned int)m_frgbaColor1.IntBlue(15.0f); + + m_pencodingbitsRGB8->individual.red2 = (unsigned int)m_frgbaColor2.IntRed(15.0f); + m_pencodingbitsRGB8->individual.green2 = (unsigned int)m_frgbaColor2.IntGreen(15.0f); + m_pencodingbitsRGB8->individual.blue2 = (unsigned int)m_frgbaColor2.IntBlue(15.0f); + } + + m_pencodingbitsRGB8->individual.cw1 = m_uiCW1; + m_pencodingbitsRGB8->individual.cw2 = m_uiCW2; + + SetEncodingBits_Selectors(); + + m_pencodingbitsRGB8->individual.diff = (unsigned int)m_boolDiff; + m_pencodingbitsRGB8->individual.flip = (unsigned int)m_boolFlip; + + } + + // ---------------------------------------------------------------------------------------------------- + // set the selectors in the encoding bits + // + void Block4x4Encoding_ETC1::SetEncodingBits_Selectors(void) + { + + m_pencodingbitsRGB8->individual.selectors = 0; + for (unsigned int uiPixel = 0; uiPixel < PIXELS; uiPixel++) + { + unsigned int uiSelector = m_auiSelectors[uiPixel]; + + // set index msb + m_pencodingbitsRGB8->individual.selectors |= (uiSelector >> 1) << (uiPixel ^ 8); + + // set index lsb + m_pencodingbitsRGB8->individual.selectors |= (uiSelector & 1) << ((16 + uiPixel) ^ 8); + } + + } + + // ---------------------------------------------------------------------------------------------------- + // set the decoded colors and decoded alpha based on the encoding state + // + void Block4x4Encoding_ETC1::Decode(void) + { + + const unsigned int *pauiPixelOrder = m_boolFlip ? s_auiPixelOrderFlip1 : s_auiPixelOrderFlip0; + + for (unsigned int uiPixelOrder = 0; uiPixelOrder < PIXELS; uiPixelOrder++) + { + ColorFloatRGBA *pfrgbaCenter = uiPixelOrder < 8 ? &m_frgbaColor1 : &m_frgbaColor2; + unsigned int uiCW = uiPixelOrder < 8 ? m_uiCW1 : m_uiCW2; + + unsigned int uiPixel = pauiPixelOrder[uiPixelOrder]; + + float fDelta = s_aafCwTable[uiCW][m_auiSelectors[uiPixel]]; + m_afrgbaDecodedColors[uiPixel] = (*pfrgbaCenter + fDelta).ClampRGB(); + m_afDecodedAlphas[uiPixel] = 1.0f; + } + + } + + // ---------------------------------------------------------------------------------------------------- + // + +} // namespace Etc |