// // Copyright (c) 2013-2015 The ANGLE Project Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // // loadimage_etc.cpp: Decodes ETC and EAC encoded textures. #include "libANGLE/renderer/d3d/loadimage_etc.h" #include "libANGLE/renderer/d3d/loadimage.h" #include "libANGLE/renderer/d3d/imageformats.h" namespace rx { namespace { // Table 3.17.2 sorted according to table 3.17.3 // clang-format off static const int intensityModifierDefault[][4] = { { 2, 8, -2, -8 }, { 5, 17, -5, -17 }, { 9, 29, -9, -29 }, { 13, 42, -13, -42 }, { 18, 60, -18, -60 }, { 24, 80, -24, -80 }, { 33, 106, -33, -106 }, { 47, 183, -47, -183 }, }; // clang-format on // Table C.12, intensity modifier for non opaque punchthrough alpha // clang-format off static const int intensityModifierNonOpaque[][4] = { { 0, 8, 0, -8 }, { 0, 17, 0, -17 }, { 0, 29, 0, -29 }, { 0, 42, 0, -42 }, { 0, 60, 0, -60 }, { 0, 80, 0, -80 }, { 0, 106, 0, -106 }, { 0, 183, 0, -183 }, }; // clang-format on // Table C.7, mapping from pixel index values to modifier value orders // clang-format off static const int valueMappingTable[] = { 2, 3, 1, 0 }; // clang-format on struct ETC2Block { // Decodes unsigned single or dual channel block to bytes void decodeAsSingleChannel(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t destPixelStride, size_t destRowPitch, bool isSigned) const { for (size_t j = 0; j < 4 && (y + j) < h; j++) { uint8_t *row = dest + (j * destRowPitch); for (size_t i = 0; i < 4 && (x + i) < w; i++) { uint8_t *pixel = row + (i * destPixelStride); if (isSigned) { *pixel = clampSByte(getSingleChannel(i, j, isSigned)); } else { *pixel = clampByte(getSingleChannel(i, j, isSigned)); } } } } // Decodes RGB block to rgba8 void decodeAsRGB(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t destRowPitch, const uint8_t alphaValues[4][4], bool punchThroughAlpha) const { bool opaqueBit = u.idht.mode.idm.diffbit; bool nonOpaquePunchThroughAlpha = punchThroughAlpha && !opaqueBit; // Select mode if (u.idht.mode.idm.diffbit || punchThroughAlpha) { const auto &block = u.idht.mode.idm.colors.diff; int r = (block.R + block.dR); int g = (block.G + block.dG); int b = (block.B + block.dB); if (r < 0 || r > 31) { decodeTBlock(dest, x, y, w, h, destRowPitch, alphaValues, nonOpaquePunchThroughAlpha); } else if (g < 0 || g > 31) { decodeHBlock(dest, x, y, w, h, destRowPitch, alphaValues, nonOpaquePunchThroughAlpha); } else if (b < 0 || b > 31) { decodePlanarBlock(dest, x, y, w, h, destRowPitch, alphaValues); } else { decodeDifferentialBlock(dest, x, y, w, h, destRowPitch, alphaValues, nonOpaquePunchThroughAlpha); } } else { decodeIndividualBlock(dest, x, y, w, h, destRowPitch, alphaValues, nonOpaquePunchThroughAlpha); } } // Transcodes RGB block to BC1 void transcodeAsBC1(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, const uint8_t alphaValues[4][4], bool punchThroughAlpha) const { bool opaqueBit = u.idht.mode.idm.diffbit; bool nonOpaquePunchThroughAlpha = punchThroughAlpha && !opaqueBit; // Select mode if (u.idht.mode.idm.diffbit || punchThroughAlpha) { const auto &block = u.idht.mode.idm.colors.diff; int r = (block.R + block.dR); int g = (block.G + block.dG); int b = (block.B + block.dB); if (r < 0 || r > 31) { transcodeTBlockToBC1(dest, x, y, w, h, alphaValues, nonOpaquePunchThroughAlpha); } else if (g < 0 || g > 31) { transcodeHBlockToBC1(dest, x, y, w, h, alphaValues, nonOpaquePunchThroughAlpha); } else if (b < 0 || b > 31) { transcodePlanarBlockToBC1(dest, x, y, w, h, alphaValues); } else { transcodeDifferentialBlockToBC1(dest, x, y, w, h, alphaValues, nonOpaquePunchThroughAlpha); } } else { transcodeIndividualBlockToBC1(dest, x, y, w, h, alphaValues, nonOpaquePunchThroughAlpha); } } private: union { // Individual, differential, H and T modes struct { union { // Individual and differential modes struct { union { struct // Individual colors { unsigned char R2 : 4; unsigned char R1 : 4; unsigned char G2 : 4; unsigned char G1 : 4; unsigned char B2 : 4; unsigned char B1 : 4; } indiv; struct // Differential colors { signed char dR : 3; unsigned char R : 5; signed char dG : 3; unsigned char G : 5; signed char dB : 3; unsigned char B : 5; } diff; } colors; bool flipbit : 1; bool diffbit : 1; unsigned char cw2 : 3; unsigned char cw1 : 3; } idm; // T mode struct { // Byte 1 unsigned char TR1b : 2; unsigned char TdummyB : 1; unsigned char TR1a : 2; unsigned char TdummyA : 3; // Byte 2 unsigned char TB1 : 4; unsigned char TG1 : 4; // Byte 3 unsigned char TG2 : 4; unsigned char TR2 : 4; // Byte 4 unsigned char Tdb : 1; bool Tflipbit : 1; unsigned char Tda : 2; unsigned char TB2 : 4; } tm; // H mode struct { // Byte 1 unsigned char HG1a : 3; unsigned char HR1 : 4; unsigned char HdummyA : 1; // Byte 2 unsigned char HB1b : 2; unsigned char HdummyC : 1; unsigned char HB1a : 1; unsigned char HG1b : 1; unsigned char HdummyB : 3; // Byte 3 unsigned char HG2a : 3; unsigned char HR2 : 4; unsigned char HB1c : 1; // Byte 4 unsigned char Hdb : 1; bool Hflipbit : 1; unsigned char Hda : 1; unsigned char HB2 : 4; unsigned char HG2b : 1; } hm; } mode; unsigned char pixelIndexMSB[2]; unsigned char pixelIndexLSB[2]; } idht; // planar mode struct { // Byte 1 unsigned char GO1 : 1; unsigned char RO : 6; unsigned char PdummyA : 1; // Byte 2 unsigned char BO1 : 1; unsigned char GO2 : 6; unsigned char PdummyB : 1; // Byte 3 unsigned char BO3a : 2; unsigned char PdummyD : 1; unsigned char BO2 : 2; unsigned char PdummyC : 3; // Byte 4 unsigned char RH2 : 1; bool Pflipbit : 1; unsigned char RH1 : 5; unsigned char BO3b : 1; // Byte 5 unsigned char BHa : 1; unsigned char GH : 7; // Byte 6 unsigned char RVa : 3; unsigned char BHb : 5; // Byte 7 unsigned char GVa : 5; unsigned char RVb : 3; // Byte 8 unsigned char BV : 6; unsigned char GVb : 2; } pblk; // Single channel block struct { union { unsigned char us; signed char s; } base_codeword; unsigned char table_index : 4; unsigned char multiplier : 4; unsigned char mc1 : 2; unsigned char mb : 3; unsigned char ma : 3; unsigned char mf1 : 1; unsigned char me : 3; unsigned char md : 3; unsigned char mc2 : 1; unsigned char mh : 3; unsigned char mg : 3; unsigned char mf2 : 2; unsigned char mk1 : 2; unsigned char mj : 3; unsigned char mi : 3; unsigned char mn1 : 1; unsigned char mm : 3; unsigned char ml : 3; unsigned char mk2 : 1; unsigned char mp : 3; unsigned char mo : 3; unsigned char mn2 : 2; } scblk; } u; static unsigned char clampByte(int value) { return static_cast(gl::clamp(value, 0, 255)); } static signed char clampSByte(int value) { return static_cast(gl::clamp(value, -128, 127)); } static R8G8B8A8 createRGBA(int red, int green, int blue, int alpha) { R8G8B8A8 rgba; rgba.R = clampByte(red); rgba.G = clampByte(green); rgba.B = clampByte(blue); rgba.A = clampByte(alpha); return rgba; } static R8G8B8A8 createRGBA(int red, int green, int blue) { return createRGBA(red, green, blue, 255); } static int extend_4to8bits(int x) { return (x << 4) | x; } static int extend_5to8bits(int x) { return (x << 3) | (x >> 2); } static int extend_6to8bits(int x) { return (x << 2) | (x >> 4); } static int extend_7to8bits(int x) { return (x << 1) | (x >> 6); } void decodeIndividualBlock(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t destRowPitch, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { const auto &block = u.idht.mode.idm.colors.indiv; int r1 = extend_4to8bits(block.R1); int g1 = extend_4to8bits(block.G1); int b1 = extend_4to8bits(block.B1); int r2 = extend_4to8bits(block.R2); int g2 = extend_4to8bits(block.G2); int b2 = extend_4to8bits(block.B2); decodeIndividualOrDifferentialBlock(dest, x, y, w, h, destRowPitch, r1, g1, b1, r2, g2, b2, alphaValues, nonOpaquePunchThroughAlpha); } void decodeDifferentialBlock(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t destRowPitch, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { const auto &block = u.idht.mode.idm.colors.diff; int b1 = extend_5to8bits(block.B); int g1 = extend_5to8bits(block.G); int r1 = extend_5to8bits(block.R); int r2 = extend_5to8bits(block.R + block.dR); int g2 = extend_5to8bits(block.G + block.dG); int b2 = extend_5to8bits(block.B + block.dB); decodeIndividualOrDifferentialBlock(dest, x, y, w, h, destRowPitch, r1, g1, b1, r2, g2, b2, alphaValues, nonOpaquePunchThroughAlpha); } void decodeIndividualOrDifferentialBlock(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t destRowPitch, int r1, int g1, int b1, int r2, int g2, int b2, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { const auto intensityModifier = nonOpaquePunchThroughAlpha ? intensityModifierNonOpaque : intensityModifierDefault; R8G8B8A8 subblockColors0[4]; R8G8B8A8 subblockColors1[4]; for (size_t modifierIdx = 0; modifierIdx < 4; modifierIdx++) { const int i1 = intensityModifier[u.idht.mode.idm.cw1][modifierIdx]; subblockColors0[modifierIdx] = createRGBA(r1 + i1, g1 + i1, b1 + i1); const int i2 = intensityModifier[u.idht.mode.idm.cw2][modifierIdx]; subblockColors1[modifierIdx] = createRGBA(r2 + i2, g2 + i2, b2 + i2); } if (u.idht.mode.idm.flipbit) { uint8_t *curPixel = dest; for (size_t j = 0; j < 2 && (y + j) < h; j++) { R8G8B8A8 *row = reinterpret_cast(curPixel); for (size_t i = 0; i < 4 && (x + i) < w; i++) { row[i] = subblockColors0[getIndex(i, j)]; row[i].A = alphaValues[j][i]; } curPixel += destRowPitch; } for (size_t j = 2; j < 4 && (y + j) < h; j++) { R8G8B8A8 *row = reinterpret_cast(curPixel); for (size_t i = 0; i < 4 && (x + i) < w; i++) { row[i] = subblockColors1[getIndex(i, j)]; row[i].A = alphaValues[j][i]; } curPixel += destRowPitch; } } else { uint8_t *curPixel = dest; for (size_t j = 0; j < 4 && (y + j) < h; j++) { R8G8B8A8 *row = reinterpret_cast(curPixel); for (size_t i = 0; i < 2 && (x + i) < w; i++) { row[i] = subblockColors0[getIndex(i, j)]; row[i].A = alphaValues[j][i]; } for (size_t i = 2; i < 4 && (x + i) < w; i++) { row[i] = subblockColors1[getIndex(i, j)]; row[i].A = alphaValues[j][i]; } curPixel += destRowPitch; } } if (nonOpaquePunchThroughAlpha) { decodePunchThroughAlphaBlock(dest, x, y, w, h, destRowPitch); } } void decodeTBlock(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t destRowPitch, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { // Table C.8, distance index for T and H modes const auto &block = u.idht.mode.tm; int r1 = extend_4to8bits(block.TR1a << 2 | block.TR1b); int g1 = extend_4to8bits(block.TG1); int b1 = extend_4to8bits(block.TB1); int r2 = extend_4to8bits(block.TR2); int g2 = extend_4to8bits(block.TG2); int b2 = extend_4to8bits(block.TB2); static int distance[8] = {3, 6, 11, 16, 23, 32, 41, 64}; const int d = distance[block.Tda << 1 | block.Tdb]; const R8G8B8A8 paintColors[4] = { createRGBA(r1, g1, b1), createRGBA(r2 + d, g2 + d, b2 + d), createRGBA(r2, g2, b2), createRGBA(r2 - d, g2 - d, b2 - d), }; uint8_t *curPixel = dest; for (size_t j = 0; j < 4 && (y + j) < h; j++) { R8G8B8A8 *row = reinterpret_cast(curPixel); for (size_t i = 0; i < 4 && (x + i) < w; i++) { row[i] = paintColors[getIndex(i, j)]; row[i].A = alphaValues[j][i]; } curPixel += destRowPitch; } if (nonOpaquePunchThroughAlpha) { decodePunchThroughAlphaBlock(dest, x, y, w, h, destRowPitch); } } void decodeHBlock(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t destRowPitch, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { // Table C.8, distance index for T and H modes const auto &block = u.idht.mode.hm; int r1 = extend_4to8bits(block.HR1); int g1 = extend_4to8bits(block.HG1a << 1 | block.HG1b); int b1 = extend_4to8bits(block.HB1a << 3 | block.HB1b << 1 | block.HB1c); int r2 = extend_4to8bits(block.HR2); int g2 = extend_4to8bits(block.HG2a << 1 | block.HG2b); int b2 = extend_4to8bits(block.HB2); static const int distance[8] = {3, 6, 11, 16, 23, 32, 41, 64}; const int d = distance[(block.Hda << 2) | (block.Hdb << 1) | ((r1 << 16 | g1 << 8 | b1) >= (r2 << 16 | g2 << 8 | b2) ? 1 : 0)]; const R8G8B8A8 paintColors[4] = { createRGBA(r1 + d, g1 + d, b1 + d), createRGBA(r1 - d, g1 - d, b1 - d), createRGBA(r2 + d, g2 + d, b2 + d), createRGBA(r2 - d, g2 - d, b2 - d), }; uint8_t *curPixel = dest; for (size_t j = 0; j < 4 && (y + j) < h; j++) { R8G8B8A8 *row = reinterpret_cast(curPixel); for (size_t i = 0; i < 4 && (x + i) < w; i++) { row[i] = paintColors[getIndex(i, j)]; row[i].A = alphaValues[j][i]; } curPixel += destRowPitch; } if (nonOpaquePunchThroughAlpha) { decodePunchThroughAlphaBlock(dest, x, y, w, h, destRowPitch); } } void decodePlanarBlock(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t pitch, const uint8_t alphaValues[4][4]) const { int ro = extend_6to8bits(u.pblk.RO); int go = extend_7to8bits(u.pblk.GO1 << 6 | u.pblk.GO2); int bo = extend_6to8bits(u.pblk.BO1 << 5 | u.pblk.BO2 << 3 | u.pblk.BO3a << 1 | u.pblk.BO3b); int rh = extend_6to8bits(u.pblk.RH1 << 1 | u.pblk.RH2); int gh = extend_7to8bits(u.pblk.GH); int bh = extend_6to8bits(u.pblk.BHa << 5 | u.pblk.BHb); int rv = extend_6to8bits(u.pblk.RVa << 3 | u.pblk.RVb); int gv = extend_7to8bits(u.pblk.GVa << 2 | u.pblk.GVb); int bv = extend_6to8bits(u.pblk.BV); uint8_t *curPixel = dest; for (size_t j = 0; j < 4 && (y + j) < h; j++) { R8G8B8A8 *row = reinterpret_cast(curPixel); int ry = static_cast(j) * (rv - ro) + 2; int gy = static_cast(j) * (gv - go) + 2; int by = static_cast(j) * (bv - bo) + 2; for (size_t i = 0; i < 4 && (x + i) < w; i++) { row[i] = createRGBA(((static_cast(i) * (rh - ro) + ry) >> 2) + ro, ((static_cast(i) * (gh - go) + gy) >> 2) + go, ((static_cast(i) * (bh - bo) + by) >> 2) + bo, alphaValues[j][i]); } curPixel += pitch; } } // Index for individual, differential, H and T modes size_t getIndex(size_t x, size_t y) const { size_t bitIndex = x * 4 + y; size_t bitOffset = bitIndex & 7; size_t lsb = (u.idht.pixelIndexLSB[1 - (bitIndex >> 3)] >> bitOffset) & 1; size_t msb = (u.idht.pixelIndexMSB[1 - (bitIndex >> 3)] >> bitOffset) & 1; return (msb << 1) | lsb; } void decodePunchThroughAlphaBlock(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, size_t destRowPitch) const { uint8_t *curPixel = dest; for (size_t j = 0; j < 4 && (y + j) < h; j++) { R8G8B8A8 *row = reinterpret_cast(curPixel); for (size_t i = 0; i < 4 && (x + i) < w; i++) { if (getIndex(i, j) == 2) // msb == 1 && lsb == 0 { row[i] = createRGBA(0, 0, 0, 0); } } curPixel += destRowPitch; } } uint16_t RGB8ToRGB565(const R8G8B8A8 &rgba) const { return (static_cast(rgba.R >> 3) << 11) | (static_cast(rgba.G >> 2) << 5) | (static_cast(rgba.B >> 3) << 0); } uint32_t matchBC1Bits(const R8G8B8A8 *rgba, const R8G8B8A8 &minColor, const R8G8B8A8 &maxColor, bool opaque) const { // Project each pixel on the (maxColor, minColor) line to decide which // BC1 code to assign to it. uint8_t decodedColors[2][3] = {{maxColor.R, maxColor.G, maxColor.B}, {minColor.R, minColor.G, minColor.B}}; int direction[3]; for (int ch = 0; ch < 3; ch++) { direction[ch] = decodedColors[0][ch] - decodedColors[1][ch]; } int stops[2]; for (int i = 0; i < 2; i++) { stops[i] = decodedColors[i][0] * direction[0] + decodedColors[i][1] * direction[1] + decodedColors[i][2] * direction[2]; } uint32_t bits = 0; if (opaque) { for (int i = 15; i >= 0; i--) { // In opaque mode, the code is from 0 to 3. bits <<= 2; const int dot = rgba[i].R * direction[0] + rgba[i].G * direction[1] + rgba[i].B * direction[2]; const int factor = gl::clamp( static_cast( (static_cast(dot - stops[1]) / (stops[0] - stops[1])) * 3 + 0.5f), 0, 3); switch (factor) { case 0: bits |= 1; break; case 1: bits |= 3; break; case 2: bits |= 2; break; case 3: default: bits |= 0; break; } } } else { for (int i = 15; i >= 0; i--) { // In non-opaque mode, 3 is for tranparent pixels. bits <<= 2; if (0 == rgba[i].A) { bits |= 3; } else { const int dot = rgba[i].R * direction[0] + rgba[i].G * direction[1] + rgba[i].B * direction[2]; const int factor = gl::clamp( static_cast( (static_cast(dot - stops[1]) / (stops[0] - stops[1])) * 2 + 0.5f), 0, 2); switch (factor) { case 0: bits |= 0; break; case 1: bits |= 2; break; case 2: default: bits |= 1; break; } } } } return bits; } void packBC1(void *bc1, const R8G8B8A8 *rgba, R8G8B8A8 &minColor, R8G8B8A8 &maxColor, bool opaque) const { uint32_t bits; uint16_t max16 = RGB8ToRGB565(maxColor); uint16_t min16 = RGB8ToRGB565(minColor); if (max16 != min16) { // Find the best BC1 code for each pixel bits = matchBC1Bits(rgba, minColor, maxColor, opaque); } else { // Same colors, BC1 index 0 is the color in both opaque and transparent mode bits = 0; // BC1 index 3 is transparent if (!opaque) { for (int i = 0; i < 16; i++) { if (0 == rgba[i].A) { bits |= (3 << (i * 2)); } } } } if (max16 < min16) { std::swap(max16, min16); uint32_t xorMask = 0; if (opaque) { // In opaque mode switching the two colors is doing the // following code swaps: 0 <-> 1 and 2 <-> 3. This is // equivalent to flipping the first bit of each code // (5 = 0b0101) xorMask = 0x55555555; } else { // In transparent mode switching the colors is doing the // following code swap: 0 <-> 1. 0xA selects the second bit of // each code, bits >> 1 selects the first bit of the code when // the seconds bit is set (case 2 and 3). We invert all the // non-selected bits, that is the first bit when the code is // 0 or 1. xorMask = ~((bits >> 1) | 0xAAAAAAAA); } bits ^= xorMask; } struct BC1Block { uint16_t color0; uint16_t color1; uint32_t bits; }; // Encode the opaqueness in the order of the two BC1 colors BC1Block *dest = reinterpret_cast(bc1); if (opaque) { dest->color0 = max16; dest->color1 = min16; } else { dest->color0 = min16; dest->color1 = max16; } dest->bits = bits; } void transcodeIndividualBlockToBC1(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { const auto &block = u.idht.mode.idm.colors.indiv; int r1 = extend_4to8bits(block.R1); int g1 = extend_4to8bits(block.G1); int b1 = extend_4to8bits(block.B1); int r2 = extend_4to8bits(block.R2); int g2 = extend_4to8bits(block.G2); int b2 = extend_4to8bits(block.B2); transcodeIndividualOrDifferentialBlockToBC1(dest, x, y, w, h, r1, g1, b1, r2, g2, b2, alphaValues, nonOpaquePunchThroughAlpha); } void transcodeDifferentialBlockToBC1(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { const auto &block = u.idht.mode.idm.colors.diff; int b1 = extend_5to8bits(block.B); int g1 = extend_5to8bits(block.G); int r1 = extend_5to8bits(block.R); int r2 = extend_5to8bits(block.R + block.dR); int g2 = extend_5to8bits(block.G + block.dG); int b2 = extend_5to8bits(block.B + block.dB); transcodeIndividualOrDifferentialBlockToBC1(dest, x, y, w, h, r1, g1, b1, r2, g2, b2, alphaValues, nonOpaquePunchThroughAlpha); } void decodeSubblock(R8G8B8A8 *rgbaBlock, size_t pixelRange[2][2], size_t x, size_t y, size_t w, size_t h, const uint8_t alphaValues[4][4], bool flipbit, size_t subblockIdx, const R8G8B8A8 subblockColors[2][4]) const { size_t dxBegin = 0; size_t dxEnd = 4; size_t dyBegin = subblockIdx * 2; size_t dyEnd = dyBegin + 2; if (!flipbit) { std::swap(dxBegin, dyBegin); std::swap(dxEnd, dyEnd); } for (size_t j = dyBegin; j < dyEnd && (y + j) < h; j++) { R8G8B8A8 *row = &rgbaBlock[j * 4]; for (size_t i = dxBegin; i < dxEnd && (x + i) < w; i++) { const size_t pixelIndex = getIndex(i, j); if (valueMappingTable[pixelIndex] < valueMappingTable[pixelRange[subblockIdx][0]]) { pixelRange[subblockIdx][0] = pixelIndex; } if (valueMappingTable[pixelIndex] > valueMappingTable[pixelRange[subblockIdx][1]]) { pixelRange[subblockIdx][1] = pixelIndex; } row[i] = subblockColors[subblockIdx][pixelIndex]; row[i].A = alphaValues[j][i]; } } } void transcodeIndividualOrDifferentialBlockToBC1(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, int r1, int g1, int b1, int r2, int g2, int b2, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { // A BC1 block has 2 endpoints, pixels is encoded as linear // interpolations of them. A ETC1/ETC2 individual or differential block // has 2 subblocks. Each subblock has one color and a modifier. We // compute the max intensity and min intensity pixel values to use as // our two BC1 endpoints and then map pixels to BC1 by projecting on the // line between the two endpoints and choosing the right fraction. // // In the future, we have 2 potential improvements to this algorithm. // 1. We don't actually need to decode ETC blocks to RGBs. Instead, // the subblock colors and pixel indices alreay contains enough // information for transcode. A direct mapping would be more // efficient here. // 2. Currently the BC1 endpoints come from the max and min intensity // of ETC colors. A principal component analysis (PCA) on them might // give us better quality results, with limited costs const auto intensityModifier = nonOpaquePunchThroughAlpha ? intensityModifierNonOpaque : intensityModifierDefault; // Compute the colors that pixels can have in each subblock both for // the decoding of the RGBA data and BC1 encoding R8G8B8A8 subblockColors[2][4]; for (size_t modifierIdx = 0; modifierIdx < 4; modifierIdx++) { const int i1 = intensityModifier[u.idht.mode.idm.cw1][modifierIdx]; subblockColors[0][modifierIdx] = createRGBA(r1 + i1, g1 + i1, b1 + i1); const int i2 = intensityModifier[u.idht.mode.idm.cw2][modifierIdx]; subblockColors[1][modifierIdx] = createRGBA(r2 + i2, g2 + i2, b2 + i2); } // 1 and 3 are the argmax and argmin of valueMappingTable size_t pixelRange[2][2] = {{1, 3}, {1, 3}}; R8G8B8A8 rgbaBlock[16]; // Decode the block in rgbaBlock and store the inverse valueTableMapping // of {min(modifier index), max(modifier index)} for (size_t blockIdx = 0; blockIdx < 2; blockIdx++) { decodeSubblock(rgbaBlock, pixelRange, x, y, w, h, alphaValues, u.idht.mode.idm.flipbit, blockIdx, subblockColors); } if (nonOpaquePunchThroughAlpha) { decodePunchThroughAlphaBlock(reinterpret_cast(rgbaBlock), x, y, w, h, sizeof(R8G8B8A8) * 4); } // Get the "min" and "max" pixel colors that have been used. R8G8B8A8 minColor; const R8G8B8A8 &minColor0 = subblockColors[0][pixelRange[0][0]]; const R8G8B8A8 &minColor1 = subblockColors[1][pixelRange[1][0]]; if (minColor0.R + minColor0.G + minColor0.B < minColor1.R + minColor1.G + minColor1.B) { minColor = minColor0; } else { minColor = minColor1; } R8G8B8A8 maxColor; const R8G8B8A8 &maxColor0 = subblockColors[0][pixelRange[0][1]]; const R8G8B8A8 &maxColor1 = subblockColors[1][pixelRange[1][1]]; if (maxColor0.R + maxColor0.G + maxColor0.B < maxColor1.R + maxColor1.G + maxColor1.B) { maxColor = maxColor1; } else { maxColor = maxColor0; } packBC1(dest, rgbaBlock, minColor, maxColor, !nonOpaquePunchThroughAlpha); } void transcodeTBlockToBC1(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { // TODO (mgong): Will be implemented soon UNIMPLEMENTED(); } void transcodeHBlockToBC1(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, const uint8_t alphaValues[4][4], bool nonOpaquePunchThroughAlpha) const { // TODO (mgong): Will be implemented soon UNIMPLEMENTED(); } void transcodePlanarBlockToBC1(uint8_t *dest, size_t x, size_t y, size_t w, size_t h, const uint8_t alphaValues[4][4]) const { // TODO (mgong): Will be implemented soon UNIMPLEMENTED(); } // Single channel utility functions int getSingleChannel(size_t x, size_t y, bool isSigned) const { int codeword = isSigned ? u.scblk.base_codeword.s : u.scblk.base_codeword.us; return codeword + getSingleChannelModifier(x, y) * u.scblk.multiplier; } int getSingleChannelIndex(size_t x, size_t y) const { ASSERT(x < 4 && y < 4); // clang-format off switch (x * 4 + y) { case 0: return u.scblk.ma; case 1: return u.scblk.mb; case 2: return u.scblk.mc1 << 1 | u.scblk.mc2; case 3: return u.scblk.md; case 4: return u.scblk.me; case 5: return u.scblk.mf1 << 2 | u.scblk.mf2; case 6: return u.scblk.mg; case 7: return u.scblk.mh; case 8: return u.scblk.mi; case 9: return u.scblk.mj; case 10: return u.scblk.mk1 << 1 | u.scblk.mk2; case 11: return u.scblk.ml; case 12: return u.scblk.mm; case 13: return u.scblk.mn1 << 2 | u.scblk.mn2; case 14: return u.scblk.mo; case 15: return u.scblk.mp; default: UNREACHABLE(); return 0; } // clang-format on } int getSingleChannelModifier(size_t x, size_t y) const { // clang-format off static const int modifierTable[16][8] = { { -3, -6, -9, -15, 2, 5, 8, 14 }, { -3, -7, -10, -13, 2, 6, 9, 12 }, { -2, -5, -8, -13, 1, 4, 7, 12 }, { -2, -4, -6, -13, 1, 3, 5, 12 }, { -3, -6, -8, -12, 2, 5, 7, 11 }, { -3, -7, -9, -11, 2, 6, 8, 10 }, { -4, -7, -8, -11, 3, 6, 7, 10 }, { -3, -5, -8, -11, 2, 4, 7, 10 }, { -2, -6, -8, -10, 1, 5, 7, 9 }, { -2, -5, -8, -10, 1, 4, 7, 9 }, { -2, -4, -8, -10, 1, 3, 7, 9 }, { -2, -5, -7, -10, 1, 4, 6, 9 }, { -3, -4, -7, -10, 2, 3, 6, 9 }, { -1, -2, -3, -10, 0, 1, 2, 9 }, { -4, -6, -8, -9, 3, 5, 7, 8 }, { -3, -5, -7, -9, 2, 4, 6, 8 } }; // clang-format on return modifierTable[u.scblk.table_index][getSingleChannelIndex(x, y)]; } }; // clang-format off static const uint8_t DefaultETCAlphaValues[4][4] = { { 255, 255, 255, 255 }, { 255, 255, 255, 255 }, { 255, 255, 255, 255 }, { 255, 255, 255, 255 }, }; // clang-format on void LoadR11EACToR8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch, bool isSigned) { for (size_t z = 0; z < depth; z++) { for (size_t y = 0; y < height; y += 4) { const ETC2Block *sourceRow = OffsetDataPointer(input, y / 4, z, inputRowPitch, inputDepthPitch); uint8_t *destRow = OffsetDataPointer(output, y, z, outputRowPitch, outputDepthPitch); for (size_t x = 0; x < width; x += 4) { const ETC2Block *sourceBlock = sourceRow + (x / 4); uint8_t *destPixels = destRow + x; sourceBlock->decodeAsSingleChannel(destPixels, x, y, width, height, 1, outputRowPitch, isSigned); } } } } void LoadRG11EACToRG8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch, bool isSigned) { for (size_t z = 0; z < depth; z++) { for (size_t y = 0; y < height; y += 4) { const ETC2Block *sourceRow = OffsetDataPointer(input, y / 4, z, inputRowPitch, inputDepthPitch); uint8_t *destRow = OffsetDataPointer(output, y, z, outputRowPitch, outputDepthPitch); for (size_t x = 0; x < width; x += 4) { uint8_t *destPixelsRed = destRow + (x * 2); const ETC2Block *sourceBlockRed = sourceRow + (x / 2); sourceBlockRed->decodeAsSingleChannel(destPixelsRed, x, y, width, height, 2, outputRowPitch, isSigned); uint8_t *destPixelsGreen = destPixelsRed + 1; const ETC2Block *sourceBlockGreen = sourceBlockRed + 1; sourceBlockGreen->decodeAsSingleChannel(destPixelsGreen, x, y, width, height, 2, outputRowPitch, isSigned); } } } } void LoadETC2RGB8ToRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch, bool punchthroughAlpha) { for (size_t z = 0; z < depth; z++) { for (size_t y = 0; y < height; y += 4) { const ETC2Block *sourceRow = OffsetDataPointer(input, y / 4, z, inputRowPitch, inputDepthPitch); uint8_t *destRow = OffsetDataPointer(output, y, z, outputRowPitch, outputDepthPitch); for (size_t x = 0; x < width; x += 4) { const ETC2Block *sourceBlock = sourceRow + (x / 4); uint8_t *destPixels = destRow + (x * 4); sourceBlock->decodeAsRGB(destPixels, x, y, width, height, outputRowPitch, DefaultETCAlphaValues, punchthroughAlpha); } } } } void LoadETC2RGB8ToBC1(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch, bool punchthroughAlpha) { for (size_t z = 0; z < depth; z++) { for (size_t y = 0; y < height; y += 4) { const ETC2Block *sourceRow = OffsetDataPointer(input, y / 4, z, inputRowPitch, inputDepthPitch); uint8_t *destRow = OffsetDataPointer(output, y / 4, z, outputRowPitch, outputDepthPitch); for (size_t x = 0; x < width; x += 4) { const ETC2Block *sourceBlock = sourceRow + (x / 4); uint8_t *destPixels = destRow + (x * 2); sourceBlock->transcodeAsBC1(destPixels, x, y, width, height, DefaultETCAlphaValues, punchthroughAlpha); } } } } void LoadETC2RGBA8ToRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch, bool srgb) { uint8_t decodedAlphaValues[4][4]; for (size_t z = 0; z < depth; z++) { for (size_t y = 0; y < height; y += 4) { const ETC2Block *sourceRow = OffsetDataPointer(input, y / 4, z, inputRowPitch, inputDepthPitch); uint8_t *destRow = OffsetDataPointer(output, y, z, outputRowPitch, outputDepthPitch); for (size_t x = 0; x < width; x += 4) { const ETC2Block *sourceBlockAlpha = sourceRow + (x / 2); sourceBlockAlpha->decodeAsSingleChannel( reinterpret_cast(decodedAlphaValues), x, y, width, height, 1, 4, false); uint8_t *destPixels = destRow + (x * 4); const ETC2Block *sourceBlockRGB = sourceBlockAlpha + 1; sourceBlockRGB->decodeAsRGB(destPixels, x, y, width, height, outputRowPitch, decodedAlphaValues, false); } } } } } // anonymous namespace void LoadETC1RGB8ToRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadETC2RGB8ToRGBA8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, false); } void LoadETC1RGB8ToBC1(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadETC2RGB8ToBC1(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, false); } void LoadEACR11ToR8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadR11EACToR8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, false); } void LoadEACR11SToR8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadR11EACToR8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, true); } void LoadEACRG11ToRG8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadRG11EACToRG8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, false); } void LoadEACRG11SToRG8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadRG11EACToRG8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, true); } void LoadETC2RGB8ToRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadETC2RGB8ToRGBA8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, false); } void LoadETC2SRGB8ToRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadETC2RGB8ToRGBA8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, false); } void LoadETC2RGB8A1ToRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadETC2RGB8ToRGBA8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, true); } void LoadETC2SRGB8A1ToRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadETC2RGB8ToRGBA8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, true); } void LoadETC2RGBA8ToRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadETC2RGBA8ToRGBA8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, false); } void LoadETC2SRGBA8ToSRGBA8(size_t width, size_t height, size_t depth, const uint8_t *input, size_t inputRowPitch, size_t inputDepthPitch, uint8_t *output, size_t outputRowPitch, size_t outputDepthPitch) { LoadETC2RGBA8ToRGBA8(width, height, depth, input, inputRowPitch, inputDepthPitch, output, outputRowPitch, outputDepthPitch, true); } } // namespace rx