Add m-esr52 at 52.6.0

1 files changed, 1572 insertions, 0 deletions

diff --git a/gfx/angle/src/image_util/loadimage_etc.cpp b/gfx/angle/src/image_util/loadimage_etc.cpp
new file mode 100755
index 000000000..b0881f728
--- /dev/null
+++ b/gfx/angle/src/image_util/loadimage_etc.cpp
@@ -0,0 +1,1572 @@
+//
+// 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
+{
+// 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
+
+static const int kNumPixelsInBlock = 16;
+
+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<unsigned char>(gl::clamp(value, 0, 255));
+    }
+
+    static signed char clampSByte(int value)
+    {
+        return static_cast<signed char>(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<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 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<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 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[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
+    {
+        // 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 =
+                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->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 =
+                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->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 =
+                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->decodeAsSingleChannel(
+                    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 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 angle