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diff --git a/gfx/angle/checkout/src/image_util/loadimage_etc.cpp b/gfx/angle/checkout/src/image_util/loadimage_etc.cpp
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+//
+// 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 "image_util/loadimage.h"
+
+#include "common/mathutil.h"
+
+#include "image_util/imageformats.h"
+
+namespace angle
+{
+namespace
+{
+
+using IntensityModifier = const int[4];
+
+// Table 3.17.2 sorted according to table 3.17.3
+// clang-format off
+static IntensityModifier intensityModifierDefault[] =
+{
+ { 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 IntensityModifier intensityModifierNonOpaque[] =
+{
+ { 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
+
+static const int kNumPixelsInBlock = 16;
+
+struct ETC2Block
+{
+ // Decodes unsigned single or dual channel ETC2 block to 8-bit color
+ void decodeAsSingleETC2Channel(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(getSingleETC2Channel(i, j, isSigned));
+ }
+ else
+ {
+ *pixel = clampByte(getSingleETC2Channel(i, j, isSigned));
+ }
+ }
+ }
+ }
+
+ // Decodes unsigned single or dual channel EAC block to 16-bit color
+ void decodeAsSingleEACChannel(uint16_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++)
+ {
+ uint16_t *row = reinterpret_cast<uint16_t *>(reinterpret_cast<uint8_t *>(dest) +
+ (j * destRowPitch));
+ for (size_t i = 0; i < 4 && (x + i) < w; i++)
+ {
+ uint16_t *pixel = row + (i * destPixelStride);
+ if (isSigned)
+ {
+ *pixel = renormalizeSignedEAC(getSingleEACChannel(i, j, isSigned));
+ }
+ else
+ {
+ *pixel = renormalizeUnsignedEAC(getSingleEACChannel(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<unsigned char>(gl::clamp(value, 0, 255));
+ }
+
+ static signed char clampSByte(int value)
+ {
+ return static_cast<signed char>(gl::clamp(value, -128, 127));
+ }
+
+ static uint16_t renormalizeUnsignedEAC(int value)
+ {
+ // Data is in the range 0 to 2047, clamp it and then scale it to 16-bit
+ return static_cast<uint16_t>(gl::clamp(value, 0, 2047)) << 5;
+ }
+
+ static int16_t renormalizeSignedEAC(int value)
+ {
+ // Data is in the range -1023 to 1023, clamp it and then scale it to 16-bit
+ // The spec states that -1024 invalid and should be clamped to -1023
+ return static_cast<int16_t>(gl::clamp(value, -1023, 1023)) * 32;
+ }
+
+ 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 IntensityModifier *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<R8G8B8A8 *>(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<R8G8B8A8 *>(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<R8G8B8A8 *>(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<R8G8B8A8 *>(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 orderingTrickBit =
+ ((r1 << 16 | g1 << 8 | b1) >= (r2 << 16 | g2 << 8 | b2) ? 1 : 0);
+ const int d = distance[(block.Hda << 2) | (block.Hdb << 1) | orderingTrickBit];
+
+ 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<R8G8B8A8 *>(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<R8G8B8A8 *>(curPixel);
+
+ int ry = static_cast<int>(j) * (rv - ro) + 2;
+ int gy = static_cast<int>(j) * (gv - go) + 2;
+ int by = static_cast<int>(j) * (bv - bo) + 2;
+ for (size_t i = 0; i < 4 && (x + i) < w; i++)
+ {
+ row[i] = createRGBA(((static_cast<int>(i) * (rh - ro) + ry) >> 2) + ro,
+ ((static_cast<int>(i) * (gh - go) + gy) >> 2) + go,
+ ((static_cast<int>(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<R8G8B8A8 *>(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<uint16_t>(rgba.R >> 3) << 11) |
+ (static_cast<uint16_t>(rgba.G >> 2) << 5) |
+ (static_cast<uint16_t>(rgba.B >> 3) << 0);
+ }
+
+ uint32_t matchBC1Bits(const int *pixelIndices,
+ const int *pixelIndexCounts,
+ const R8G8B8A8 *subblockColors,
+ size_t numColors,
+ const R8G8B8A8 &minColor,
+ const R8G8B8A8 &maxColor,
+ bool nonOpaquePunchThroughAlpha) 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];
+ }
+
+ ASSERT(numColors <= kNumPixelsInBlock);
+
+ int encodedColors[kNumPixelsInBlock];
+ if (nonOpaquePunchThroughAlpha)
+ {
+ for (size_t i = 0; i < numColors; i++)
+ {
+ const int count = pixelIndexCounts[i];
+ if (count > 0)
+ {
+ // In non-opaque mode, 3 is for tranparent pixels.
+
+ if (0 == subblockColors[i].A)
+ {
+ encodedColors[i] = 3;
+ }
+ else
+ {
+ const R8G8B8A8 &pixel = subblockColors[i];
+ const int dot = pixel.R * direction[0] + pixel.G * direction[1] +
+ pixel.B * direction[2];
+ const int factor = gl::clamp(
+ static_cast<int>(
+ (static_cast<float>(dot - stops[1]) / (stops[0] - stops[1])) * 2 +
+ 0.5f),
+ 0, 2);
+ switch (factor)
+ {
+ case 0:
+ encodedColors[i] = 0;
+ break;
+ case 1:
+ encodedColors[i] = 2;
+ break;
+ case 2:
+ default:
+ encodedColors[i] = 1;
+ break;
+ }
+ }
+ }
+ }
+ }
+ else
+ {
+ for (size_t i = 0; i < numColors; i++)
+ {
+ const int count = pixelIndexCounts[i];
+ if (count > 0)
+ {
+ // In opaque mode, the code is from 0 to 3.
+
+ const R8G8B8A8 &pixel = subblockColors[i];
+ const int dot =
+ pixel.R * direction[0] + pixel.G * direction[1] + pixel.B * direction[2];
+ const int factor = gl::clamp(
+ static_cast<int>(
+ (static_cast<float>(dot - stops[1]) / (stops[0] - stops[1])) * 3 +
+ 0.5f),
+ 0, 3);
+ switch (factor)
+ {
+ case 0:
+ encodedColors[i] = 1;
+ break;
+ case 1:
+ encodedColors[i] = 3;
+ break;
+ case 2:
+ encodedColors[i] = 2;
+ break;
+ case 3:
+ default:
+ encodedColors[i] = 0;
+ break;
+ }
+ }
+ }
+ }
+
+ uint32_t bits = 0;
+ for (int i = kNumPixelsInBlock - 1; i >= 0; i--)
+ {
+ bits <<= 2;
+ bits |= encodedColors[pixelIndices[i]];
+ }
+
+ return bits;
+ }
+
+ void packBC1(void *bc1,
+ const int *pixelIndices,
+ const int *pixelIndexCounts,
+ const R8G8B8A8 *subblockColors,
+ size_t numColors,
+ int minColorIndex,
+ int maxColorIndex,
+ bool nonOpaquePunchThroughAlpha) const
+ {
+ const R8G8B8A8 &minColor = subblockColors[minColorIndex];
+ const R8G8B8A8 &maxColor = subblockColors[maxColorIndex];
+
+ 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(pixelIndices, pixelIndexCounts, subblockColors, numColors, minColor,
+ maxColor, nonOpaquePunchThroughAlpha);
+ }
+ else
+ {
+ // Same colors, BC1 index 0 is the color in both opaque and transparent mode
+ bits = 0;
+ // BC1 index 3 is transparent
+ if (nonOpaquePunchThroughAlpha)
+ {
+ for (int i = 0; i < kNumPixelsInBlock; i++)
+ {
+ if (0 == subblockColors[pixelIndices[i]].A)
+ {
+ bits |= (3 << (i * 2));
+ }
+ }
+ }
+ }
+
+ if (max16 < min16)
+ {
+ std::swap(max16, min16);
+
+ uint32_t xorMask = 0;
+ if (nonOpaquePunchThroughAlpha)
+ {
+ // 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);
+ }
+ else
+ {
+ // 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;
+ }
+ 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<BC1Block *>(bc1);
+ if (nonOpaquePunchThroughAlpha)
+ {
+ dest->color0 = min16;
+ dest->color1 = max16;
+ }
+ else
+ {
+ dest->color0 = max16;
+ dest->color1 = min16;
+ }
+ 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 extractPixelIndices(int *pixelIndices,
+ int *pixelIndicesCounts,
+ size_t x,
+ size_t y,
+ size_t w,
+ size_t h,
+ bool flipbit,
+ size_t subblockIdx) 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; j++)
+ {
+ int *row = &pixelIndices[j * 4];
+ for (size_t i = dxBegin; i < dxEnd; i++)
+ {
+ const size_t pixelIndex = subblockIdx * 4 + getIndex(i, j);
+ row[i] = static_cast<int>(pixelIndex);
+ pixelIndicesCounts[pixelIndex]++;
+ }
+ }
+ }
+
+ void selectEndPointPCA(const int *pixelIndexCounts,
+ const R8G8B8A8 *subblockColors,
+ size_t numColors,
+ int *minColorIndex,
+ int *maxColorIndex) const
+ {
+ // determine color distribution
+ int mu[3], min[3], max[3];
+ for (int ch = 0; ch < 3; ch++)
+ {
+ int muv = 0;
+ int minv = 255;
+ int maxv = 0;
+ for (size_t i = 0; i < numColors; i++)
+ {
+ const int count = pixelIndexCounts[i];
+ if (count > 0)
+ {
+ const auto &pixel = subblockColors[i];
+ if (pixel.A > 0)
+ {
+ // Non-transparent pixels
+ muv += (&pixel.R)[ch] * count;
+ minv = std::min<int>(minv, (&pixel.R)[ch]);
+ maxv = std::max<int>(maxv, (&pixel.R)[ch]);
+ }
+ }
+ }
+
+ mu[ch] = (muv + kNumPixelsInBlock / 2) / kNumPixelsInBlock;
+ min[ch] = minv;
+ max[ch] = maxv;
+ }
+
+ // determine covariance matrix
+ int cov[6] = {0, 0, 0, 0, 0, 0};
+ for (size_t i = 0; i < numColors; i++)
+ {
+ const int count = pixelIndexCounts[i];
+ if (count > 0)
+ {
+ const auto &pixel = subblockColors[i];
+ if (pixel.A > 0)
+ {
+ int r = pixel.R - mu[0];
+ int g = pixel.G - mu[1];
+ int b = pixel.B - mu[2];
+
+ cov[0] += r * r * count;
+ cov[1] += r * g * count;
+ cov[2] += r * b * count;
+ cov[3] += g * g * count;
+ cov[4] += g * b * count;
+ cov[5] += b * b * count;
+ }
+ }
+ }
+
+ // Power iteration algorithm to get the eigenvalues and eigenvector
+
+ // Starts with diagonal vector
+ float vfr = static_cast<float>(max[0] - min[0]);
+ float vfg = static_cast<float>(max[1] - min[1]);
+ float vfb = static_cast<float>(max[2] - min[2]);
+ float eigenvalue;
+
+ static const size_t kPowerIterations = 4;
+ for (size_t i = 0; i < kPowerIterations; i++)
+ {
+ float r = vfr * cov[0] + vfg * cov[1] + vfb * cov[2];
+ float g = vfr * cov[1] + vfg * cov[3] + vfb * cov[4];
+ float b = vfr * cov[2] + vfg * cov[4] + vfb * cov[5];
+
+ vfr = r;
+ vfg = g;
+ vfb = b;
+
+ eigenvalue = sqrt(r * r + g * g + b * b);
+ if (eigenvalue > 0)
+ {
+ float invNorm = 1.0f / eigenvalue;
+ vfr *= invNorm;
+ vfg *= invNorm;
+ vfb *= invNorm;
+ }
+ }
+
+ int vr, vg, vb;
+
+ static const float kDefaultLuminanceThreshold = 4.0f * 255;
+ static const float kQuantizeRange = 512.0f;
+ if (eigenvalue < kDefaultLuminanceThreshold) // too small, default to luminance
+ {
+ // Luminance weights defined by ITU-R Recommendation BT.601, scaled by 1000
+ vr = 299;
+ vg = 587;
+ vb = 114;
+ }
+ else
+ {
+ // From the eigenvalue and eigenvector, choose the axis to project
+ // colors on. When projecting colors we want to do integer computations
+ // for speed, so we normalize the eigenvector to the [0, 512] range.
+ float magn = std::max(std::max(std::abs(vfr), std::abs(vfg)), std::abs(vfb));
+ magn = kQuantizeRange / magn;
+ vr = static_cast<int>(vfr * magn);
+ vg = static_cast<int>(vfg * magn);
+ vb = static_cast<int>(vfb * magn);
+ }
+
+ // Pick colors at extreme points
+ int minD = INT_MAX;
+ int maxD = 0;
+ size_t minIndex = 0;
+ size_t maxIndex = 0;
+ for (size_t i = 0; i < numColors; i++)
+ {
+ const int count = pixelIndexCounts[i];
+ if (count > 0)
+ {
+ const auto &pixel = subblockColors[i];
+ if (pixel.A > 0)
+ {
+ int dot = pixel.R * vr + pixel.G * vg + pixel.B * vb;
+ if (dot < minD)
+ {
+ minD = dot;
+ minIndex = i;
+ }
+ if (dot > maxD)
+ {
+ maxD = dot;
+ maxIndex = i;
+ }
+ }
+ }
+ }
+
+ *minColorIndex = static_cast<int>(minIndex);
+ *maxColorIndex = static_cast<int>(maxIndex);
+ }
+
+ 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
+ // select axis by principal component analysis (PCA) 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.
+
+ // The goal of this algorithm is make it faster than decode ETC to RGBs
+ // and then encode to BC. To achieve this, we only extract subblock
+ // colors, pixel indices, and counts of each pixel indices from ETC.
+ // With those information, we can only encode used subblock colors
+ // to BC1, and copy the bits to the right pixels.
+ // Fully decode and encode need to process 16 RGBA pixels. With this
+ // algorithm, it's 8 pixels at maximum for a individual or
+ // differential block. Saves us bandwidth and computations.
+
+ static const size_t kNumColors = 8;
+
+ const IntensityModifier *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[kNumColors];
+ for (size_t modifierIdx = 0; modifierIdx < 4; modifierIdx++)
+ {
+ if (nonOpaquePunchThroughAlpha && (modifierIdx == 2))
+ {
+ // In ETC opaque punch through formats, individual and
+ // differential blocks take index 2 as transparent pixel.
+ // Thus we don't need to compute its color, just assign it
+ // as black.
+ subblockColors[modifierIdx] = createRGBA(0, 0, 0, 0);
+ subblockColors[4 + modifierIdx] = createRGBA(0, 0, 0, 0);
+ }
+ else
+ {
+ const int i1 = intensityModifier[u.idht.mode.idm.cw1][modifierIdx];
+ subblockColors[modifierIdx] = createRGBA(r1 + i1, g1 + i1, b1 + i1);
+
+ const int i2 = intensityModifier[u.idht.mode.idm.cw2][modifierIdx];
+ subblockColors[4 + modifierIdx] = createRGBA(r2 + i2, g2 + i2, b2 + i2);
+ }
+ }
+
+ int pixelIndices[kNumPixelsInBlock];
+ int pixelIndexCounts[kNumColors] = {0};
+ // Extract pixel indices from a ETC block.
+ for (size_t blockIdx = 0; blockIdx < 2; blockIdx++)
+ {
+ extractPixelIndices(pixelIndices, pixelIndexCounts, x, y, w, h, u.idht.mode.idm.flipbit,
+ blockIdx);
+ }
+
+ int minColorIndex, maxColorIndex;
+ selectEndPointPCA(pixelIndexCounts, subblockColors, kNumColors, &minColorIndex,
+ &maxColorIndex);
+
+ packBC1(dest, pixelIndices, pixelIndexCounts, subblockColors, kNumColors, minColorIndex,
+ maxColorIndex, 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
+ {
+ static const size_t kNumColors = 4;
+
+ // 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];
+
+ // In ETC opaque punch through formats, index == 2 means transparent pixel.
+ // Thus we don't need to compute its color, just assign it as black.
+ const R8G8B8A8 paintColors[kNumColors] = {
+ createRGBA(r1, g1, b1),
+ createRGBA(r2 + d, g2 + d, b2 + d),
+ nonOpaquePunchThroughAlpha ? createRGBA(0, 0, 0, 0) : createRGBA(r2, g2, b2),
+ createRGBA(r2 - d, g2 - d, b2 - d),
+ };
+
+ int pixelIndices[kNumPixelsInBlock];
+ int pixelIndexCounts[kNumColors] = {0};
+ for (size_t j = 0; j < 4; j++)
+ {
+ int *row = &pixelIndices[j * 4];
+ for (size_t i = 0; i < 4; i++)
+ {
+ const size_t pixelIndex = getIndex(i, j);
+ row[i] = static_cast<int>(pixelIndex);
+ pixelIndexCounts[pixelIndex]++;
+ }
+ }
+
+ int minColorIndex, maxColorIndex;
+ selectEndPointPCA(pixelIndexCounts, paintColors, kNumColors, &minColorIndex,
+ &maxColorIndex);
+
+ packBC1(dest, pixelIndices, pixelIndexCounts, paintColors, kNumColors, minColorIndex,
+ maxColorIndex, nonOpaquePunchThroughAlpha);
+ }
+
+ 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
+ {
+ static const size_t kNumColors = 4;
+
+ // 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 orderingTrickBit =
+ ((r1 << 16 | g1 << 8 | b1) >= (r2 << 16 | g2 << 8 | b2) ? 1 : 0);
+ const int d = distance[(block.Hda << 2) | (block.Hdb << 1) | orderingTrickBit];
+
+ // In ETC opaque punch through formats, index == 2 means transparent pixel.
+ // Thus we don't need to compute its color, just assign it as black.
+ const R8G8B8A8 paintColors[kNumColors] = {
+ createRGBA(r1 + d, g1 + d, b1 + d),
+ createRGBA(r1 - d, g1 - d, b1 - d),
+ nonOpaquePunchThroughAlpha ? createRGBA(0, 0, 0, 0)
+ : createRGBA(r2 + d, g2 + d, b2 + d),
+ createRGBA(r2 - d, g2 - d, b2 - d),
+ };
+
+ int pixelIndices[kNumPixelsInBlock];
+ int pixelIndexCounts[kNumColors] = {0};
+ for (size_t j = 0; j < 4; j++)
+ {
+ int *row = &pixelIndices[j * 4];
+ for (size_t i = 0; i < 4; i++)
+ {
+ const size_t pixelIndex = getIndex(i, j);
+ row[i] = static_cast<int>(pixelIndex);
+ pixelIndexCounts[pixelIndex]++;
+ }
+ }
+
+ int minColorIndex, maxColorIndex;
+ selectEndPointPCA(pixelIndexCounts, paintColors, kNumColors, &minColorIndex,
+ &maxColorIndex);
+
+ packBC1(dest, pixelIndices, pixelIndexCounts, paintColors, kNumColors, minColorIndex,
+ maxColorIndex, nonOpaquePunchThroughAlpha);
+ }
+
+ void transcodePlanarBlockToBC1(uint8_t *dest,
+ size_t x,
+ size_t y,
+ size_t w,
+ size_t h,
+ const uint8_t alphaValues[4][4]) const
+ {
+ static const size_t kNumColors = kNumPixelsInBlock;
+
+ R8G8B8A8 rgbaBlock[kNumColors];
+ decodePlanarBlock(reinterpret_cast<uint8_t *>(rgbaBlock), x, y, w, h, sizeof(R8G8B8A8) * 4,
+ alphaValues);
+
+ // Planar block doesn't have a color table, fill indices as full
+ int pixelIndices[kNumPixelsInBlock] = {0, 1, 2, 3, 4, 5, 6, 7,
+ 8, 9, 10, 11, 12, 13, 14, 15};
+ int pixelIndexCounts[kNumColors] = {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1};
+
+ int minColorIndex, maxColorIndex;
+ selectEndPointPCA(pixelIndexCounts, rgbaBlock, kNumColors, &minColorIndex, &maxColorIndex);
+
+ packBC1(dest, pixelIndices, pixelIndexCounts, rgbaBlock, kNumColors, minColorIndex,
+ maxColorIndex, false);
+ }
+
+ // Single channel utility functions
+ int getSingleEACChannel(size_t x, size_t y, bool isSigned) const
+ {
+ int codeword = isSigned ? u.scblk.base_codeword.s : u.scblk.base_codeword.us;
+ int multiplier = (u.scblk.multiplier == 0) ? 1 : u.scblk.multiplier * 8;
+ return codeword * 8 + 4 + getSingleChannelModifier(x, y) * multiplier;
+ }
+
+ int getSingleETC2Channel(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 =
+ priv::OffsetDataPointer<ETC2Block>(input, y / 4, z, inputRowPitch, inputDepthPitch);
+ uint8_t *destRow =
+ priv::OffsetDataPointer<uint8_t>(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->decodeAsSingleETC2Channel(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 =
+ priv::OffsetDataPointer<ETC2Block>(input, y / 4, z, inputRowPitch, inputDepthPitch);
+ uint8_t *destRow =
+ priv::OffsetDataPointer<uint8_t>(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->decodeAsSingleETC2Channel(destPixelsRed, x, y, width, height, 2,
+ outputRowPitch, isSigned);
+
+ uint8_t *destPixelsGreen = destPixelsRed + 1;
+ const ETC2Block *sourceBlockGreen = sourceBlockRed + 1;
+ sourceBlockGreen->decodeAsSingleETC2Channel(destPixelsGreen, x, y, width, height, 2,
+ outputRowPitch, isSigned);
+ }
+ }
+ }
+}
+
+void LoadR11EACToR16(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 =
+ priv::OffsetDataPointer<ETC2Block>(input, y / 4, z, inputRowPitch, inputDepthPitch);
+ uint16_t *destRow =
+ priv::OffsetDataPointer<uint16_t>(output, y, z, outputRowPitch, outputDepthPitch);
+
+ for (size_t x = 0; x < width; x += 4)
+ {
+ const ETC2Block *sourceBlock = sourceRow + (x / 4);
+ uint16_t *destPixels = destRow + x;
+
+ sourceBlock->decodeAsSingleEACChannel(destPixels, x, y, width, height, 1,
+ outputRowPitch, isSigned);
+ }
+ }
+ }
+}
+
+void LoadRG11EACToRG16(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 =
+ priv::OffsetDataPointer<ETC2Block>(input, y / 4, z, inputRowPitch, inputDepthPitch);
+ uint16_t *destRow =
+ priv::OffsetDataPointer<uint16_t>(output, y, z, outputRowPitch, outputDepthPitch);
+
+ for (size_t x = 0; x < width; x += 4)
+ {
+ uint16_t *destPixelsRed = destRow + (x * 2);
+ const ETC2Block *sourceBlockRed = sourceRow + (x / 2);
+ sourceBlockRed->decodeAsSingleEACChannel(destPixelsRed, x, y, width, height, 2,
+ outputRowPitch, isSigned);
+
+ uint16_t *destPixelsGreen = destPixelsRed + 1;
+ const ETC2Block *sourceBlockGreen = sourceBlockRed + 1;
+ sourceBlockGreen->decodeAsSingleEACChannel(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 =
+ priv::OffsetDataPointer<ETC2Block>(input, y / 4, z, inputRowPitch, inputDepthPitch);
+ uint8_t *destRow =
+ priv::OffsetDataPointer<uint8_t>(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 =
+ priv::OffsetDataPointer<ETC2Block>(input, y / 4, z, inputRowPitch, inputDepthPitch);
+ uint8_t *destRow = priv::OffsetDataPointer<uint8_t>(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 =
+ priv::OffsetDataPointer<ETC2Block>(input, y / 4, z, inputRowPitch, inputDepthPitch);
+ uint8_t *destRow =
+ priv::OffsetDataPointer<uint8_t>(output, y, z, outputRowPitch, outputDepthPitch);
+
+ for (size_t x = 0; x < width; x += 4)
+ {
+ const ETC2Block *sourceBlockAlpha = sourceRow + (x / 2);
+ sourceBlockAlpha->decodeAsSingleETC2Channel(
+ reinterpret_cast<uint8_t *>(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 LoadEACR11ToR16(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)
+{
+ LoadR11EACToR16(width, height, depth, input, inputRowPitch, inputDepthPitch, output,
+ outputRowPitch, outputDepthPitch, false);
+}
+
+void LoadEACR11SToR16(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)
+{
+ LoadR11EACToR16(width, height, depth, input, inputRowPitch, inputDepthPitch, output,
+ outputRowPitch, outputDepthPitch, true);
+}
+
+void LoadEACRG11ToRG16(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)
+{
+ LoadRG11EACToRG16(width, height, depth, input, inputRowPitch, inputDepthPitch, output,
+ outputRowPitch, outputDepthPitch, false);
+}
+
+void LoadEACRG11SToRG16(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)
+{
+ LoadRG11EACToRG16(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 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)
+{
+ LoadETC2RGB8ToBC1(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 LoadETC2SRGB8ToBC1(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 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 LoadETC2RGB8A1ToBC1(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, 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 LoadETC2SRGB8A1ToBC1(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, 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 angle
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 07:15:54 +0000