From 2d133177e979bd68eba1a241cae84a8215087993 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?R=C3=A9mi=20Verschelde?= Date: Fri, 7 May 2021 17:00:41 +0200 Subject: basis_universal: Update to upstream commit from Apr 16, 2021 BinomialLLC/basis_universal@ba1c3e40f1d434ebaf9a167b44e9b11d2bf0f765. --- thirdparty/basis_universal/encoder/basisu_etc.cpp | 1593 +++++++++++++++++++++ 1 file changed, 1593 insertions(+) create mode 100644 thirdparty/basis_universal/encoder/basisu_etc.cpp (limited to 'thirdparty/basis_universal/encoder/basisu_etc.cpp') diff --git a/thirdparty/basis_universal/encoder/basisu_etc.cpp b/thirdparty/basis_universal/encoder/basisu_etc.cpp new file mode 100644 index 0000000000..232e8965b0 --- /dev/null +++ b/thirdparty/basis_universal/encoder/basisu_etc.cpp @@ -0,0 +1,1593 @@ +// basis_etc.cpp +// Copyright (C) 2019-2021 Binomial LLC. All Rights Reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +#include "basisu_etc.h" + +#if BASISU_SUPPORT_SSE +#define CPPSPMD_NAME(a) a##_sse41 +#include "basisu_kernels_declares.h" +#endif + +#define BASISU_DEBUG_ETC_ENCODER 0 +#define BASISU_DEBUG_ETC_ENCODER_DEEPER 0 + +namespace basisu +{ + const int8_t g_etc2_eac_tables[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 } + }; + + const int8_t g_etc2_eac_tables8[16][8] = + { + { -24, -48, -72, -120, 16, 40, 64, 112 }, { -24,-56,-80,-104,16,48,72,96 }, { -16,-40,-64,-104,8,32,56,96 }, { -16,-32,-48,-104,8,24,40,96 }, + { -24,-48,-64,-96,16,40,56,88 }, { -24,-56,-72,-88,16,48,64,80 }, { -32,-56,-64,-88,24,48,56,80 }, { -24,-40,-64,-88,16,32,56,80 }, + { -16,-48,-64,-80,8,40,56,72 }, { -16,-40,-64,-80,8,32,56,72 }, { -16,-32,-64,-80,8,24,56,72 }, { -16,-40,-56,-80,8,32,48,72 }, + { -24,-32,-56,-80,16,24,48,72 }, { -8,-16,-24,-80,0,8,16,72 }, { -32,-48,-64,-72,24,40,56,64 }, { -24,-40,-56,-72,16,32,48,64 } + }; + + // Given an ETC1 diff/inten_table/selector, and an 8-bit desired color, this table encodes the best packed_color in the low byte, and the abs error in the high byte. + static uint16_t g_etc1_inverse_lookup[2 * 8 * 4][256]; // [ diff/inten_table/selector][desired_color ] + + // g_color8_to_etc_block_config[color][table_index] = Supplies for each 8-bit color value a list of packed ETC1 diff/intensity table/selectors/packed_colors that map to that color. + // To pack: diff | (inten << 1) | (selector << 4) | (packed_c << 8) + static const uint16_t g_etc1_color8_to_etc_block_config_0_255[2][33] = + { + { 0x0000, 0x0010, 0x0002, 0x0012, 0x0004, 0x0014, 0x0006, 0x0016, 0x0008, 0x0018, 0x000A, 0x001A, 0x000C, 0x001C, 0x000E, 0x001E, 0x0001, 0x0011, 0x0003, 0x0013, 0x0005, 0x0015, 0x0007, 0x0017, 0x0009, 0x0019, 0x000B, 0x001B, 0x000D, 0x001D, 0x000F, 0x001F, 0xFFFF }, + { 0x0F20, 0x0F30, 0x0E32, 0x0F22, 0x0E34, 0x0F24, 0x0D36, 0x0F26, 0x0C38, 0x0E28, 0x0B3A, 0x0E2A, 0x093C, 0x0E2C, 0x053E, 0x0D2E, 0x1E31, 0x1F21, 0x1D33, 0x1F23, 0x1C35, 0x1E25, 0x1A37, 0x1E27, 0x1839, 0x1D29, 0x163B, 0x1C2B, 0x133D, 0x1B2D, 0x093F, 0x1A2F, 0xFFFF }, + }; + + // Really only [254][11]. + static const uint16_t g_etc1_color8_to_etc_block_config_1_to_254[254][12] = + { + { 0x021C, 0x0D0D, 0xFFFF }, { 0x0020, 0x0021, 0x0A0B, 0x061F, 0xFFFF }, { 0x0113, 0x0217, 0xFFFF }, { 0x0116, 0x031E, 0x0B0E, 0x0405, 0xFFFF }, { 0x0022, 0x0204, 0x050A, 0x0023, 0xFFFF }, { 0x0111, 0x0319, 0x0809, 0x170F, 0xFFFF }, { + 0x0303, 0x0215, 0x0607, 0xFFFF }, { 0x0030, 0x0114, 0x0408, 0x0031, 0x0201, 0x051D, 0xFFFF }, { 0x0100, 0x0024, 0x0306, 0x0025, 0x041B, 0x0E0D, 0xFFFF }, { 0x021A, 0x0121, 0x0B0B, 0x071F, 0xFFFF }, { 0x0213, 0x0317, 0xFFFF }, { 0x0112, + 0x0505, 0xFFFF }, { 0x0026, 0x070C, 0x0123, 0x0027, 0xFFFF }, { 0x0211, 0x0909, 0xFFFF }, { 0x0110, 0x0315, 0x0707, 0x0419, 0x180F, 0xFFFF }, { 0x0218, 0x0131, 0x0301, 0x0403, 0x061D, 0xFFFF }, { 0x0032, 0x0202, 0x0033, 0x0125, 0x051B, + 0x0F0D, 0xFFFF }, { 0x0028, 0x031C, 0x0221, 0x0029, 0xFFFF }, { 0x0120, 0x0313, 0x0C0B, 0x081F, 0xFFFF }, { 0x0605, 0x0417, 0xFFFF }, { 0x0216, 0x041E, 0x0C0E, 0x0223, 0x0127, 0xFFFF }, { 0x0122, 0x0304, 0x060A, 0x0311, 0x0A09, 0xFFFF + }, { 0x0519, 0x190F, 0xFFFF }, { 0x002A, 0x0231, 0x0503, 0x0415, 0x0807, 0x002B, 0x071D, 0xFFFF }, { 0x0130, 0x0214, 0x0508, 0x0401, 0x0133, 0x0225, 0x061B, 0xFFFF }, { 0x0200, 0x0124, 0x0406, 0x0321, 0x0129, 0x100D, 0xFFFF }, { 0x031A, + 0x0D0B, 0x091F, 0xFFFF }, { 0x0413, 0x0705, 0x0517, 0xFFFF }, { 0x0212, 0x0034, 0x0323, 0x0035, 0x0227, 0xFFFF }, { 0x0126, 0x080C, 0x0B09, 0xFFFF }, { 0x0411, 0x0619, 0x1A0F, 0xFFFF }, { 0x0210, 0x0331, 0x0603, 0x0515, 0x0907, 0x012B, + 0xFFFF }, { 0x0318, 0x002C, 0x0501, 0x0233, 0x0325, 0x071B, 0x002D, 0x081D, 0xFFFF }, { 0x0132, 0x0302, 0x0229, 0x110D, 0xFFFF }, { 0x0128, 0x041C, 0x0421, 0x0E0B, 0x0A1F, 0xFFFF }, { 0x0220, 0x0513, 0x0617, 0xFFFF }, { 0x0135, 0x0805, + 0x0327, 0xFFFF }, { 0x0316, 0x051E, 0x0D0E, 0x0423, 0xFFFF }, { 0x0222, 0x0404, 0x070A, 0x0511, 0x0719, 0x0C09, 0x1B0F, 0xFFFF }, { 0x0703, 0x0615, 0x0A07, 0x022B, 0xFFFF }, { 0x012A, 0x0431, 0x0601, 0x0333, 0x012D, 0x091D, 0xFFFF }, { + 0x0230, 0x0314, 0x0036, 0x0608, 0x0425, 0x0037, 0x0329, 0x081B, 0x120D, 0xFFFF }, { 0x0300, 0x0224, 0x0506, 0x0521, 0x0F0B, 0x0B1F, 0xFFFF }, { 0x041A, 0x0613, 0x0717, 0xFFFF }, { 0x0235, 0x0905, 0xFFFF }, { 0x0312, 0x0134, 0x0523, + 0x0427, 0xFFFF }, { 0x0226, 0x090C, 0x002E, 0x0611, 0x0D09, 0x002F, 0xFFFF }, { 0x0715, 0x0B07, 0x0819, 0x032B, 0x1C0F, 0xFFFF }, { 0x0310, 0x0531, 0x0701, 0x0803, 0x022D, 0x0A1D, 0xFFFF }, { 0x0418, 0x012C, 0x0433, 0x0525, 0x0137, 0x091B, + 0x130D, 0xFFFF }, { 0x0232, 0x0402, 0x0621, 0x0429, 0xFFFF }, { 0x0228, 0x051C, 0x0713, 0x100B, 0x0C1F, 0xFFFF }, { 0x0320, 0x0335, 0x0A05, 0x0817, 0xFFFF }, { 0x0623, 0x0527, 0xFFFF }, { 0x0416, 0x061E, 0x0E0E, 0x0711, 0x0E09, 0x012F, + 0xFFFF }, { 0x0322, 0x0504, 0x080A, 0x0919, 0x1D0F, 0xFFFF }, { 0x0631, 0x0903, 0x0815, 0x0C07, 0x042B, 0x032D, 0x0B1D, 0xFFFF }, { 0x022A, 0x0801, 0x0533, 0x0625, 0x0237, 0x0A1B, 0xFFFF }, { 0x0330, 0x0414, 0x0136, 0x0708, 0x0721, 0x0529, + 0x140D, 0xFFFF }, { 0x0400, 0x0324, 0x0606, 0x0038, 0x0039, 0x110B, 0x0D1F, 0xFFFF }, { 0x051A, 0x0813, 0x0B05, 0x0917, 0xFFFF }, { 0x0723, 0x0435, 0x0627, 0xFFFF }, { 0x0412, 0x0234, 0x0F09, 0x022F, 0xFFFF }, { 0x0326, 0x0A0C, 0x012E, + 0x0811, 0x0A19, 0x1E0F, 0xFFFF }, { 0x0731, 0x0A03, 0x0915, 0x0D07, 0x052B, 0xFFFF }, { 0x0410, 0x0901, 0x0633, 0x0725, 0x0337, 0x0B1B, 0x042D, 0x0C1D, 0xFFFF }, { 0x0518, 0x022C, 0x0629, 0x150D, 0xFFFF }, { 0x0332, 0x0502, 0x0821, 0x0139, + 0x120B, 0x0E1F, 0xFFFF }, { 0x0328, 0x061C, 0x0913, 0x0A17, 0xFFFF }, { 0x0420, 0x0535, 0x0C05, 0x0727, 0xFFFF }, { 0x0823, 0x032F, 0xFFFF }, { 0x0516, 0x071E, 0x0F0E, 0x0911, 0x0B19, 0x1009, 0x1F0F, 0xFFFF }, { 0x0422, 0x0604, 0x090A, + 0x0B03, 0x0A15, 0x0E07, 0x062B, 0xFFFF }, { 0x0831, 0x0A01, 0x0733, 0x052D, 0x0D1D, 0xFFFF }, { 0x032A, 0x0825, 0x0437, 0x0729, 0x0C1B, 0x160D, 0xFFFF }, { 0x0430, 0x0514, 0x0236, 0x0808, 0x0921, 0x0239, 0x130B, 0x0F1F, 0xFFFF }, { 0x0500, + 0x0424, 0x0706, 0x0138, 0x0A13, 0x0B17, 0xFFFF }, { 0x061A, 0x0635, 0x0D05, 0xFFFF }, { 0x0923, 0x0827, 0xFFFF }, { 0x0512, 0x0334, 0x003A, 0x0A11, 0x1109, 0x003B, 0x042F, 0xFFFF }, { 0x0426, 0x0B0C, 0x022E, 0x0B15, 0x0F07, 0x0C19, + 0x072B, 0xFFFF }, { 0x0931, 0x0B01, 0x0C03, 0x062D, 0x0E1D, 0xFFFF }, { 0x0510, 0x0833, 0x0925, 0x0537, 0x0D1B, 0x170D, 0xFFFF }, { 0x0618, 0x032C, 0x0A21, 0x0339, 0x0829, 0xFFFF }, { 0x0432, 0x0602, 0x0B13, 0x140B, 0x101F, 0xFFFF }, { + 0x0428, 0x071C, 0x0735, 0x0E05, 0x0C17, 0xFFFF }, { 0x0520, 0x0A23, 0x0927, 0xFFFF }, { 0x0B11, 0x1209, 0x013B, 0x052F, 0xFFFF }, { 0x0616, 0x081E, 0x0D19, 0xFFFF }, { 0x0522, 0x0704, 0x0A0A, 0x0A31, 0x0D03, 0x0C15, 0x1007, 0x082B, 0x072D, + 0x0F1D, 0xFFFF }, { 0x0C01, 0x0933, 0x0A25, 0x0637, 0x0E1B, 0xFFFF }, { 0x042A, 0x0B21, 0x0929, 0x180D, 0xFFFF }, { 0x0530, 0x0614, 0x0336, 0x0908, 0x0439, 0x150B, 0x111F, 0xFFFF }, { 0x0600, 0x0524, 0x0806, 0x0238, 0x0C13, 0x0F05, + 0x0D17, 0xFFFF }, { 0x071A, 0x0B23, 0x0835, 0x0A27, 0xFFFF }, { 0x1309, 0x023B, 0x062F, 0xFFFF }, { 0x0612, 0x0434, 0x013A, 0x0C11, 0x0E19, 0xFFFF }, { 0x0526, 0x0C0C, 0x032E, 0x0B31, 0x0E03, 0x0D15, 0x1107, 0x092B, 0xFFFF }, { 0x0D01, + 0x0A33, 0x0B25, 0x0737, 0x0F1B, 0x082D, 0x101D, 0xFFFF }, { 0x0610, 0x0A29, 0x190D, 0xFFFF }, { 0x0718, 0x042C, 0x0C21, 0x0539, 0x160B, 0x121F, 0xFFFF }, { 0x0532, 0x0702, 0x0D13, 0x0E17, 0xFFFF }, { 0x0528, 0x081C, 0x0935, 0x1005, 0x0B27, + 0xFFFF }, { 0x0620, 0x0C23, 0x033B, 0x072F, 0xFFFF }, { 0x0D11, 0x0F19, 0x1409, 0xFFFF }, { 0x0716, 0x003C, 0x091E, 0x0F03, 0x0E15, 0x1207, 0x0A2B, 0x003D, 0xFFFF }, { 0x0622, 0x0804, 0x0B0A, 0x0C31, 0x0E01, 0x0B33, 0x092D, 0x111D, + 0xFFFF }, { 0x0C25, 0x0837, 0x0B29, 0x101B, 0x1A0D, 0xFFFF }, { 0x052A, 0x0D21, 0x0639, 0x170B, 0x131F, 0xFFFF }, { 0x0630, 0x0714, 0x0436, 0x0A08, 0x0E13, 0x0F17, 0xFFFF }, { 0x0700, 0x0624, 0x0906, 0x0338, 0x0A35, 0x1105, 0xFFFF }, { + 0x081A, 0x0D23, 0x0C27, 0xFFFF }, { 0x0E11, 0x1509, 0x043B, 0x082F, 0xFFFF }, { 0x0712, 0x0534, 0x023A, 0x0F15, 0x1307, 0x1019, 0x0B2B, 0x013D, 0xFFFF }, { 0x0626, 0x0D0C, 0x042E, 0x0D31, 0x0F01, 0x1003, 0x0A2D, 0x121D, 0xFFFF }, { 0x0C33, + 0x0D25, 0x0937, 0x111B, 0x1B0D, 0xFFFF }, { 0x0710, 0x0E21, 0x0739, 0x0C29, 0xFFFF }, { 0x0818, 0x052C, 0x0F13, 0x180B, 0x141F, 0xFFFF }, { 0x0632, 0x0802, 0x0B35, 0x1205, 0x1017, 0xFFFF }, { 0x0628, 0x091C, 0x0E23, 0x0D27, 0xFFFF }, { + 0x0720, 0x0F11, 0x1609, 0x053B, 0x092F, 0xFFFF }, { 0x1119, 0x023D, 0xFFFF }, { 0x0816, 0x013C, 0x0A1E, 0x0E31, 0x1103, 0x1015, 0x1407, 0x0C2B, 0x0B2D, 0x131D, 0xFFFF }, { 0x0722, 0x0904, 0x0C0A, 0x1001, 0x0D33, 0x0E25, 0x0A37, 0x121B, + 0xFFFF }, { 0x0F21, 0x0D29, 0x1C0D, 0xFFFF }, { 0x062A, 0x0839, 0x190B, 0x151F, 0xFFFF }, { 0x0730, 0x0814, 0x0536, 0x0B08, 0x1013, 0x1305, 0x1117, 0xFFFF }, { 0x0800, 0x0724, 0x0A06, 0x0438, 0x0F23, 0x0C35, 0x0E27, 0xFFFF }, { 0x091A, + 0x1709, 0x063B, 0x0A2F, 0xFFFF }, { 0x1011, 0x1219, 0x033D, 0xFFFF }, { 0x0812, 0x0634, 0x033A, 0x0F31, 0x1203, 0x1115, 0x1507, 0x0D2B, 0xFFFF }, { 0x0726, 0x0E0C, 0x052E, 0x1101, 0x0E33, 0x0F25, 0x0B37, 0x131B, 0x0C2D, 0x141D, 0xFFFF }, { + 0x0E29, 0x1D0D, 0xFFFF }, { 0x0810, 0x1021, 0x0939, 0x1A0B, 0x161F, 0xFFFF }, { 0x0918, 0x062C, 0x1113, 0x1217, 0xFFFF }, { 0x0732, 0x0902, 0x0D35, 0x1405, 0x0F27, 0xFFFF }, { 0x0728, 0x0A1C, 0x1023, 0x073B, 0x0B2F, 0xFFFF }, { 0x0820, + 0x1111, 0x1319, 0x1809, 0xFFFF }, { 0x1303, 0x1215, 0x1607, 0x0E2B, 0x043D, 0xFFFF }, { 0x0916, 0x023C, 0x0B1E, 0x1031, 0x1201, 0x0F33, 0x0D2D, 0x151D, 0xFFFF }, { 0x0822, 0x0A04, 0x0D0A, 0x1025, 0x0C37, 0x0F29, 0x141B, 0x1E0D, 0xFFFF }, { + 0x1121, 0x0A39, 0x1B0B, 0x171F, 0xFFFF }, { 0x072A, 0x1213, 0x1317, 0xFFFF }, { 0x0830, 0x0914, 0x0636, 0x0C08, 0x0E35, 0x1505, 0xFFFF }, { 0x0900, 0x0824, 0x0B06, 0x0538, 0x1123, 0x1027, 0xFFFF }, { 0x0A1A, 0x1211, 0x1909, 0x083B, 0x0C2F, + 0xFFFF }, { 0x1315, 0x1707, 0x1419, 0x0F2B, 0x053D, 0xFFFF }, { 0x0912, 0x0734, 0x043A, 0x1131, 0x1301, 0x1403, 0x0E2D, 0x161D, 0xFFFF }, { 0x0826, 0x0F0C, 0x062E, 0x1033, 0x1125, 0x0D37, 0x151B, 0x1F0D, 0xFFFF }, { 0x1221, 0x0B39, 0x1029, + 0xFFFF }, { 0x0910, 0x1313, 0x1C0B, 0x181F, 0xFFFF }, { 0x0A18, 0x072C, 0x0F35, 0x1605, 0x1417, 0xFFFF }, { 0x0832, 0x0A02, 0x1223, 0x1127, 0xFFFF }, { 0x0828, 0x0B1C, 0x1311, 0x1A09, 0x093B, 0x0D2F, 0xFFFF }, { 0x0920, 0x1519, 0x063D, + 0xFFFF }, { 0x1231, 0x1503, 0x1415, 0x1807, 0x102B, 0x0F2D, 0x171D, 0xFFFF }, { 0x0A16, 0x033C, 0x0C1E, 0x1401, 0x1133, 0x1225, 0x0E37, 0x161B, 0xFFFF }, { 0x0922, 0x0B04, 0x0E0A, 0x1321, 0x1129, 0xFFFF }, { 0x0C39, 0x1D0B, 0x191F, 0xFFFF + }, { 0x082A, 0x1413, 0x1705, 0x1517, 0xFFFF }, { 0x0930, 0x0A14, 0x0736, 0x0D08, 0x1323, 0x1035, 0x1227, 0xFFFF }, { 0x0A00, 0x0924, 0x0C06, 0x0638, 0x1B09, 0x0A3B, 0x0E2F, 0xFFFF }, { 0x0B1A, 0x1411, 0x1619, 0x073D, 0xFFFF }, { 0x1331, + 0x1603, 0x1515, 0x1907, 0x112B, 0xFFFF }, { 0x0A12, 0x0834, 0x053A, 0x1501, 0x1233, 0x1325, 0x0F37, 0x171B, 0x102D, 0x181D, 0xFFFF }, { 0x0926, 0x072E, 0x1229, 0xFFFF }, { 0x1421, 0x0D39, 0x1E0B, 0x1A1F, 0xFFFF }, { 0x0A10, 0x1513, + 0x1617, 0xFFFF }, { 0x0B18, 0x082C, 0x1135, 0x1805, 0x1327, 0xFFFF }, { 0x0932, 0x0B02, 0x1423, 0x0B3B, 0x0F2F, 0xFFFF }, { 0x0928, 0x0C1C, 0x1511, 0x1719, 0x1C09, 0xFFFF }, { 0x0A20, 0x1703, 0x1615, 0x1A07, 0x122B, 0x083D, 0xFFFF }, { + 0x1431, 0x1601, 0x1333, 0x112D, 0x191D, 0xFFFF }, { 0x0B16, 0x043C, 0x0D1E, 0x1425, 0x1037, 0x1329, 0x181B, 0xFFFF }, { 0x0A22, 0x0C04, 0x0F0A, 0x1521, 0x0E39, 0x1F0B, 0x1B1F, 0xFFFF }, { 0x1613, 0x1717, 0xFFFF }, { 0x092A, 0x1235, 0x1905, + 0xFFFF }, { 0x0A30, 0x0B14, 0x0836, 0x0E08, 0x1523, 0x1427, 0xFFFF }, { 0x0B00, 0x0A24, 0x0D06, 0x0738, 0x1611, 0x1D09, 0x0C3B, 0x102F, 0xFFFF }, { 0x0C1A, 0x1715, 0x1B07, 0x1819, 0x132B, 0x093D, 0xFFFF }, { 0x1531, 0x1701, 0x1803, 0x122D, + 0x1A1D, 0xFFFF }, { 0x0B12, 0x0934, 0x063A, 0x1433, 0x1525, 0x1137, 0x191B, 0xFFFF }, { 0x0A26, 0x003E, 0x082E, 0x1621, 0x0F39, 0x1429, 0x003F, 0xFFFF }, { 0x1713, 0x1C1F, 0xFFFF }, { 0x0B10, 0x1335, 0x1A05, 0x1817, 0xFFFF }, { 0x0C18, + 0x092C, 0x1623, 0x1527, 0xFFFF }, { 0x0A32, 0x0C02, 0x1711, 0x1E09, 0x0D3B, 0x112F, 0xFFFF }, { 0x0A28, 0x0D1C, 0x1919, 0x0A3D, 0xFFFF }, { 0x0B20, 0x1631, 0x1903, 0x1815, 0x1C07, 0x142B, 0x132D, 0x1B1D, 0xFFFF }, { 0x1801, 0x1533, 0x1625, + 0x1237, 0x1A1B, 0xFFFF }, { 0x0C16, 0x053C, 0x0E1E, 0x1721, 0x1529, 0x013F, 0xFFFF }, { 0x0B22, 0x0D04, 0x1039, 0x1D1F, 0xFFFF }, { 0x1813, 0x1B05, 0x1917, 0xFFFF }, { 0x0A2A, 0x1723, 0x1435, 0x1627, 0xFFFF }, { 0x0B30, 0x0C14, 0x0936, + 0x0F08, 0x1F09, 0x0E3B, 0x122F, 0xFFFF }, { 0x0C00, 0x0B24, 0x0E06, 0x0838, 0x1811, 0x1A19, 0x0B3D, 0xFFFF }, { 0x0D1A, 0x1731, 0x1A03, 0x1915, 0x1D07, 0x152B, 0xFFFF }, { 0x1901, 0x1633, 0x1725, 0x1337, 0x1B1B, 0x142D, 0x1C1D, 0xFFFF }, { + 0x0C12, 0x0A34, 0x073A, 0x1629, 0x023F, 0xFFFF }, { 0x0B26, 0x013E, 0x092E, 0x1821, 0x1139, 0x1E1F, 0xFFFF }, { 0x1913, 0x1A17, 0xFFFF }, { 0x0C10, 0x1535, 0x1C05, 0x1727, 0xFFFF }, { 0x0D18, 0x0A2C, 0x1823, 0x0F3B, 0x132F, 0xFFFF }, { + 0x0B32, 0x0D02, 0x1911, 0x1B19, 0xFFFF }, { 0x0B28, 0x0E1C, 0x1B03, 0x1A15, 0x1E07, 0x162B, 0x0C3D, 0xFFFF }, { 0x0C20, 0x1831, 0x1A01, 0x1733, 0x152D, 0x1D1D, 0xFFFF }, { 0x1825, 0x1437, 0x1729, 0x1C1B, 0x033F, 0xFFFF }, { 0x0D16, 0x063C, + 0x0F1E, 0x1921, 0x1239, 0x1F1F, 0xFFFF }, { 0x0C22, 0x0E04, 0x1A13, 0x1B17, 0xFFFF }, { 0x1635, 0x1D05, 0xFFFF }, { 0x0B2A, 0x1923, 0x1827, 0xFFFF }, { 0x0C30, 0x0D14, 0x0A36, 0x1A11, 0x103B, 0x142F, 0xFFFF }, { 0x0D00, 0x0C24, 0x0F06, + 0x0938, 0x1B15, 0x1F07, 0x1C19, 0x172B, 0x0D3D, 0xFFFF }, { 0x0E1A, 0x1931, 0x1B01, 0x1C03, 0x162D, 0x1E1D, 0xFFFF }, { 0x1833, 0x1925, 0x1537, 0x1D1B, 0xFFFF }, { 0x0D12, 0x0B34, 0x083A, 0x1A21, 0x1339, 0x1829, 0x043F, 0xFFFF }, { 0x0C26, + 0x023E, 0x0A2E, 0x1B13, 0xFFFF }, { 0x1735, 0x1E05, 0x1C17, 0xFFFF }, { 0x0D10, 0x1A23, 0x1927, 0xFFFF }, { 0x0E18, 0x0B2C, 0x1B11, 0x113B, 0x152F, 0xFFFF }, { 0x0C32, 0x0E02, 0x1D19, 0x0E3D, 0xFFFF }, { 0x0C28, 0x0F1C, 0x1A31, 0x1D03, + 0x1C15, 0x182B, 0x172D, 0x1F1D, 0xFFFF }, { 0x0D20, 0x1C01, 0x1933, 0x1A25, 0x1637, 0x1E1B, 0xFFFF }, { 0x1B21, 0x1929, 0x053F, 0xFFFF }, { 0x0E16, 0x073C, 0x1439, 0xFFFF }, { 0x0D22, 0x0F04, 0x1C13, 0x1F05, 0x1D17, 0xFFFF }, { 0x1B23, + 0x1835, 0x1A27, 0xFFFF }, { 0x0C2A, 0x123B, 0x162F, 0xFFFF }, { 0x0D30, 0x0E14, 0x0B36, 0x1C11, 0x1E19, 0x0F3D, 0xFFFF }, { 0x0E00, 0x0D24, 0x0A38, 0x1B31, 0x1E03, 0x1D15, 0x192B, 0xFFFF }, { 0x0F1A, 0x1D01, 0x1A33, 0x1B25, 0x1737, 0x1F1B, + 0x182D, 0xFFFF }, { 0x1A29, 0x063F, 0xFFFF }, { 0x0E12, 0x0C34, 0x093A, 0x1C21, 0x1539, 0xFFFF }, { 0x0D26, 0x033E, 0x0B2E, 0x1D13, 0x1E17, 0xFFFF }, { 0x1935, 0x1B27, 0xFFFF }, { 0x0E10, 0x1C23, 0x133B, 0x172F, 0xFFFF }, { 0x0F18, + 0x0C2C, 0x1D11, 0x1F19, 0xFFFF }, { 0x0D32, 0x0F02, 0x1F03, 0x1E15, 0x1A2B, 0x103D, 0xFFFF }, { 0x0D28, 0x1C31, 0x1E01, 0x1B33, 0x192D, 0xFFFF }, { 0x0E20, 0x1C25, 0x1837, 0x1B29, 0x073F, 0xFFFF }, { 0x1D21, 0x1639, 0xFFFF }, { 0x0F16, + 0x083C, 0x1E13, 0x1F17, 0xFFFF }, { 0x0E22, 0x1A35, 0xFFFF }, { 0x1D23, 0x1C27, 0xFFFF }, { 0x0D2A, 0x1E11, 0x143B, 0x182F, 0xFFFF }, { 0x0E30, 0x0F14, 0x0C36, 0x1F15, 0x1B2B, 0x113D, 0xFFFF }, { 0x0F00, 0x0E24, 0x0B38, 0x1D31, 0x1F01, + 0x1A2D, 0xFFFF }, { 0x1C33, 0x1D25, 0x1937, 0xFFFF }, { 0x1E21, 0x1739, 0x1C29, 0x083F, 0xFFFF }, { 0x0F12, 0x0D34, 0x0A3A, 0x1F13, 0xFFFF }, { 0x0E26, 0x043E, 0x0C2E, 0x1B35, 0xFFFF }, { 0x1E23, 0x1D27, 0xFFFF }, { 0x0F10, 0x1F11, 0x153B, 0x192F, 0xFFFF }, { 0x0D2C, 0x123D, 0xFFFF }, + }; + + static uint32_t etc1_decode_value(uint32_t diff, uint32_t inten, uint32_t selector, uint32_t packed_c) + { + const uint32_t limit = diff ? 32 : 16; + BASISU_NOTE_UNUSED(limit); + assert((diff < 2) && (inten < 8) && (selector < 4) && (packed_c < limit)); + int c; + if (diff) + c = (packed_c >> 2) | (packed_c << 3); + else + c = packed_c | (packed_c << 4); + c += g_etc1_inten_tables[inten][selector]; + c = clamp(c, 0, 255); + return c; + } + + void pack_etc1_solid_color_init() + { + for (uint32_t diff = 0; diff < 2; diff++) + { + const uint32_t limit = diff ? 32 : 16; + + for (uint32_t inten = 0; inten < 8; inten++) + { + for (uint32_t selector = 0; selector < 4; selector++) + { + const uint32_t inverse_table_index = diff + (inten << 1) + (selector << 4); + for (uint32_t color = 0; color < 256; color++) + { + uint32_t best_error = UINT32_MAX, best_packed_c = 0; + for (uint32_t packed_c = 0; packed_c < limit; packed_c++) + { + int v = etc1_decode_value(diff, inten, selector, packed_c); + uint32_t err = (uint32_t)labs(v - static_cast(color)); + if (err < best_error) + { + best_error = err; + best_packed_c = packed_c; + if (!best_error) + break; + } + } + assert(best_error <= 255); + g_etc1_inverse_lookup[inverse_table_index][color] = static_cast(best_packed_c | (best_error << 8)); + } + } + } + } + } + + // Packs solid color blocks efficiently using a set of small precomputed tables. + // For random 888 inputs, MSE results are better than Erricson's ETC1 packer in "slow" mode ~9.5% of the time, is slightly worse only ~.01% of the time, and is equal the rest of the time. + uint64_t pack_etc1_block_solid_color(etc_block& block, const uint8_t* pColor) + { + assert(g_etc1_inverse_lookup[0][255]); + + static uint32_t s_next_comp[4] = { 1, 2, 0, 1 }; + + uint32_t best_error = UINT32_MAX, best_i = 0; + int best_x = 0, best_packed_c1 = 0, best_packed_c2 = 0; + + // For each possible 8-bit value, there is a precomputed list of diff/inten/selector configurations that allow that 8-bit value to be encoded with no error. + for (uint32_t i = 0; i < 3; i++) + { + const uint32_t c1 = pColor[s_next_comp[i]], c2 = pColor[s_next_comp[i + 1]]; + + const int delta_range = 1; + for (int delta = -delta_range; delta <= delta_range; delta++) + { + const int c_plus_delta = clamp(pColor[i] + delta, 0, 255); + + const uint16_t* pTable; + if (!c_plus_delta) + pTable = g_etc1_color8_to_etc_block_config_0_255[0]; + else if (c_plus_delta == 255) + pTable = g_etc1_color8_to_etc_block_config_0_255[1]; + else + pTable = g_etc1_color8_to_etc_block_config_1_to_254[c_plus_delta - 1]; + + do + { + const uint32_t x = *pTable++; + +#ifdef _DEBUG + const uint32_t diff = x & 1; + const uint32_t inten = (x >> 1) & 7; + const uint32_t selector = (x >> 4) & 3; + const uint32_t p0 = (x >> 8) & 255; + assert(etc1_decode_value(diff, inten, selector, p0) == (uint32_t)c_plus_delta); +#endif + + const uint16_t* pInverse_table = g_etc1_inverse_lookup[x & 0xFF]; + uint16_t p1 = pInverse_table[c1]; + uint16_t p2 = pInverse_table[c2]; + const uint32_t trial_error = square(c_plus_delta - pColor[i]) + square(p1 >> 8) + square(p2 >> 8); + if (trial_error < best_error) + { + best_error = trial_error; + best_x = x; + best_packed_c1 = p1 & 0xFF; + best_packed_c2 = p2 & 0xFF; + best_i = i; + if (!best_error) + goto found_perfect_match; + } + } while (*pTable != 0xFFFF); + } + } + found_perfect_match: + + const uint32_t diff = best_x & 1; + const uint32_t inten = (best_x >> 1) & 7; + + block.m_bytes[3] = static_cast(((inten | (inten << 3)) << 2) | (diff << 1)); + + const uint32_t etc1_selector = g_selector_index_to_etc1[(best_x >> 4) & 3]; + *reinterpret_cast(&block.m_bytes[4]) = (etc1_selector & 2) ? 0xFFFF : 0; + *reinterpret_cast(&block.m_bytes[6]) = (etc1_selector & 1) ? 0xFFFF : 0; + + const uint32_t best_packed_c0 = (best_x >> 8) & 255; + if (diff) + { + block.m_bytes[best_i] = static_cast(best_packed_c0 << 3); + block.m_bytes[s_next_comp[best_i]] = static_cast(best_packed_c1 << 3); + block.m_bytes[s_next_comp[best_i + 1]] = static_cast(best_packed_c2 << 3); + } + else + { + block.m_bytes[best_i] = static_cast(best_packed_c0 | (best_packed_c0 << 4)); + block.m_bytes[s_next_comp[best_i]] = static_cast(best_packed_c1 | (best_packed_c1 << 4)); + block.m_bytes[s_next_comp[best_i + 1]] = static_cast(best_packed_c2 | (best_packed_c2 << 4)); + } + + return best_error; + } + + const uint32_t BASISU_ETC1_CLUSTER_FIT_ORDER_TABLE_SIZE = 165; + + static const struct { uint8_t m_v[4]; } g_cluster_fit_order_tab[BASISU_ETC1_CLUSTER_FIT_ORDER_TABLE_SIZE] = + { + { { 0, 0, 0, 8 } },{ { 0, 5, 2, 1 } },{ { 0, 6, 1, 1 } },{ { 0, 7, 0, 1 } },{ { 0, 7, 1, 0 } }, + { { 0, 0, 8, 0 } },{ { 0, 0, 3, 5 } },{ { 0, 1, 7, 0 } },{ { 0, 0, 4, 4 } },{ { 0, 0, 2, 6 } }, + { { 0, 0, 7, 1 } },{ { 0, 0, 1, 7 } },{ { 0, 0, 5, 3 } },{ { 1, 6, 0, 1 } },{ { 0, 0, 6, 2 } }, + { { 0, 2, 6, 0 } },{ { 2, 4, 2, 0 } },{ { 0, 3, 5, 0 } },{ { 3, 3, 1, 1 } },{ { 4, 2, 0, 2 } }, + { { 1, 5, 2, 0 } },{ { 0, 5, 3, 0 } },{ { 0, 6, 2, 0 } },{ { 2, 4, 1, 1 } },{ { 5, 1, 0, 2 } }, + { { 6, 1, 1, 0 } },{ { 3, 3, 0, 2 } },{ { 6, 0, 0, 2 } },{ { 0, 8, 0, 0 } },{ { 6, 1, 0, 1 } }, + { { 0, 1, 6, 1 } },{ { 1, 6, 1, 0 } },{ { 4, 1, 3, 0 } },{ { 0, 2, 5, 1 } },{ { 5, 0, 3, 0 } }, + { { 5, 3, 0, 0 } },{ { 0, 1, 5, 2 } },{ { 0, 3, 4, 1 } },{ { 2, 5, 1, 0 } },{ { 1, 7, 0, 0 } }, + { { 0, 1, 4, 3 } },{ { 6, 0, 2, 0 } },{ { 0, 4, 4, 0 } },{ { 2, 6, 0, 0 } },{ { 0, 2, 4, 2 } }, + { { 0, 5, 1, 2 } },{ { 0, 6, 0, 2 } },{ { 3, 5, 0, 0 } },{ { 0, 4, 3, 1 } },{ { 3, 4, 1, 0 } }, + { { 4, 3, 1, 0 } },{ { 1, 5, 0, 2 } },{ { 0, 3, 3, 2 } },{ { 1, 4, 1, 2 } },{ { 0, 4, 2, 2 } }, + { { 2, 3, 3, 0 } },{ { 4, 4, 0, 0 } },{ { 1, 2, 4, 1 } },{ { 0, 5, 0, 3 } },{ { 0, 1, 3, 4 } }, + { { 1, 5, 1, 1 } },{ { 1, 4, 2, 1 } },{ { 1, 3, 2, 2 } },{ { 5, 2, 1, 0 } },{ { 1, 3, 3, 1 } }, + { { 0, 1, 2, 5 } },{ { 1, 1, 5, 1 } },{ { 0, 3, 2, 3 } },{ { 2, 5, 0, 1 } },{ { 3, 2, 2, 1 } }, + { { 2, 3, 0, 3 } },{ { 1, 4, 3, 0 } },{ { 2, 2, 1, 3 } },{ { 6, 2, 0, 0 } },{ { 1, 0, 6, 1 } }, + { { 3, 3, 2, 0 } },{ { 7, 1, 0, 0 } },{ { 3, 1, 4, 0 } },{ { 0, 2, 3, 3 } },{ { 0, 4, 1, 3 } }, + { { 0, 4, 0, 4 } },{ { 0, 1, 0, 7 } },{ { 2, 0, 5, 1 } },{ { 2, 0, 4, 2 } },{ { 3, 0, 2, 3 } }, + { { 2, 2, 4, 0 } },{ { 2, 2, 3, 1 } },{ { 4, 0, 3, 1 } },{ { 3, 2, 3, 0 } },{ { 2, 3, 2, 1 } }, + { { 1, 3, 4, 0 } },{ { 7, 0, 1, 0 } },{ { 3, 0, 4, 1 } },{ { 1, 0, 5, 2 } },{ { 8, 0, 0, 0 } }, + { { 3, 0, 1, 4 } },{ { 4, 1, 1, 2 } },{ { 4, 0, 2, 2 } },{ { 1, 2, 5, 0 } },{ { 4, 2, 1, 1 } }, + { { 3, 4, 0, 1 } },{ { 2, 0, 3, 3 } },{ { 5, 0, 1, 2 } },{ { 5, 0, 0, 3 } },{ { 2, 4, 0, 2 } }, + { { 2, 1, 4, 1 } },{ { 4, 0, 1, 3 } },{ { 2, 1, 5, 0 } },{ { 4, 2, 2, 0 } },{ { 4, 0, 4, 0 } }, + { { 1, 0, 4, 3 } },{ { 1, 4, 0, 3 } },{ { 3, 0, 3, 2 } },{ { 4, 3, 0, 1 } },{ { 0, 1, 1, 6 } }, + { { 1, 3, 1, 3 } },{ { 0, 2, 2, 4 } },{ { 2, 0, 2, 4 } },{ { 5, 1, 1, 1 } },{ { 3, 0, 5, 0 } }, + { { 2, 3, 1, 2 } },{ { 3, 0, 0, 5 } },{ { 0, 3, 1, 4 } },{ { 5, 0, 2, 1 } },{ { 2, 1, 3, 2 } }, + { { 2, 0, 6, 0 } },{ { 3, 1, 3, 1 } },{ { 5, 1, 2, 0 } },{ { 1, 0, 3, 4 } },{ { 1, 1, 6, 0 } }, + { { 4, 0, 0, 4 } },{ { 2, 0, 1, 5 } },{ { 0, 3, 0, 5 } },{ { 1, 3, 0, 4 } },{ { 4, 1, 2, 1 } }, + { { 1, 2, 3, 2 } },{ { 3, 1, 0, 4 } },{ { 5, 2, 0, 1 } },{ { 1, 2, 2, 3 } },{ { 3, 2, 1, 2 } }, + { { 2, 2, 2, 2 } },{ { 6, 0, 1, 1 } },{ { 1, 2, 1, 4 } },{ { 1, 1, 4, 2 } },{ { 3, 2, 0, 3 } }, + { { 1, 2, 0, 5 } },{ { 1, 0, 7, 0 } },{ { 3, 1, 2, 2 } },{ { 1, 0, 2, 5 } },{ { 2, 0, 0, 6 } }, + { { 2, 1, 1, 4 } },{ { 2, 2, 0, 4 } },{ { 1, 1, 3, 3 } },{ { 7, 0, 0, 1 } },{ { 1, 0, 0, 7 } }, + { { 2, 1, 2, 3 } },{ { 4, 1, 0, 3 } },{ { 3, 1, 1, 3 } },{ { 1, 1, 2, 4 } },{ { 2, 1, 0, 5 } }, + { { 1, 0, 1, 6 } },{ { 0, 2, 1, 5 } },{ { 0, 2, 0, 6 } },{ { 1, 1, 1, 5 } },{ { 1, 1, 0, 6 } } + }; + + const int g_etc1_inten_tables[cETC1IntenModifierValues][cETC1SelectorValues] = + { + { -8, -2, 2, 8 }, { -17, -5, 5, 17 }, { -29, -9, 9, 29 }, { -42, -13, 13, 42 }, + { -60, -18, 18, 60 }, { -80, -24, 24, 80 }, { -106, -33, 33, 106 }, { -183, -47, 47, 183 } + }; + + const uint8_t g_etc1_to_selector_index[cETC1SelectorValues] = { 2, 3, 1, 0 }; + const uint8_t g_selector_index_to_etc1[cETC1SelectorValues] = { 3, 2, 0, 1 }; + + // [flip][subblock][pixel_index] + const etc_coord2 g_etc1_pixel_coords[2][2][8] = + { + { + { + { 0, 0 }, { 0, 1 }, { 0, 2 }, { 0, 3 }, + { 1, 0 }, { 1, 1 }, { 1, 2 }, { 1, 3 } + }, + { + { 2, 0 }, { 2, 1 }, { 2, 2 }, { 2, 3 }, + { 3, 0 }, { 3, 1 }, { 3, 2 }, { 3, 3 } + } + }, + { + { + { 0, 0 }, { 1, 0 }, { 2, 0 }, { 3, 0 }, + { 0, 1 }, { 1, 1 }, { 2, 1 }, { 3, 1 } + }, + { + { 0, 2 }, { 1, 2 }, { 2, 2 }, { 3, 2 }, + { 0, 3 }, { 1, 3 }, { 2, 3 }, { 3, 3 } + }, + } + }; + + // [flip][subblock][pixel_index] + const uint32_t g_etc1_pixel_indices[2][2][8] = + { + { + { + 0 + 4 * 0, 0 + 4 * 1, 0 + 4 * 2, 0 + 4 * 3, + 1 + 4 * 0, 1 + 4 * 1, 1 + 4 * 2, 1 + 4 * 3 + }, + { + 2 + 4 * 0, 2 + 4 * 1, 2 + 4 * 2, 2 + 4 * 3, + 3 + 4 * 0, 3 + 4 * 1, 3 + 4 * 2, 3 + 4 * 3 + } + }, + { + { + 0 + 4 * 0, 1 + 4 * 0, 2 + 4 * 0, 3 + 4 * 0, + 0 + 4 * 1, 1 + 4 * 1, 2 + 4 * 1, 3 + 4 * 1 + }, + { + 0 + 4 * 2, 1 + 4 * 2, 2 + 4 * 2, 3 + 4 * 2, + 0 + 4 * 3, 1 + 4 * 3, 2 + 4 * 3, 3 + 4 * 3 + }, + } + }; + + uint16_t etc_block::pack_color5(const color_rgba& color, bool scaled, uint32_t bias) + { + return pack_color5(color.r, color.g, color.b, scaled, bias); + } + + uint16_t etc_block::pack_color5(uint32_t r, uint32_t g, uint32_t b, bool scaled, uint32_t bias) + { + if (scaled) + { + r = (r * 31U + bias) / 255U; + g = (g * 31U + bias) / 255U; + b = (b * 31U + bias) / 255U; + } + + r = minimum(r, 31U); + g = minimum(g, 31U); + b = minimum(b, 31U); + + return static_cast(b | (g << 5U) | (r << 10U)); + } + + color_rgba etc_block::unpack_color5(uint16_t packed_color5, bool scaled, uint32_t alpha) + { + uint32_t b = packed_color5 & 31U; + uint32_t g = (packed_color5 >> 5U) & 31U; + uint32_t r = (packed_color5 >> 10U) & 31U; + + if (scaled) + { + b = (b << 3U) | (b >> 2U); + g = (g << 3U) | (g >> 2U); + r = (r << 3U) | (r >> 2U); + } + + return color_rgba(cNoClamp, r, g, b, minimum(alpha, 255U)); + } + + void etc_block::unpack_color5(color_rgba& result, uint16_t packed_color5, bool scaled) + { + result = unpack_color5(packed_color5, scaled, 255); + } + + void etc_block::unpack_color5(uint32_t& r, uint32_t& g, uint32_t& b, uint16_t packed_color5, bool scaled) + { + color_rgba c(unpack_color5(packed_color5, scaled, 0)); + r = c.r; + g = c.g; + b = c.b; + } + + bool etc_block::unpack_color5(color_rgba& result, uint16_t packed_color5, uint16_t packed_delta3, bool scaled, uint32_t alpha) + { + color_rgba_i16 dc(unpack_delta3(packed_delta3)); + + int b = (packed_color5 & 31U) + dc.b; + int g = ((packed_color5 >> 5U) & 31U) + dc.g; + int r = ((packed_color5 >> 10U) & 31U) + dc.r; + + bool success = true; + if (static_cast(r | g | b) > 31U) + { + success = false; + r = clamp(r, 0, 31); + g = clamp(g, 0, 31); + b = clamp(b, 0, 31); + } + + if (scaled) + { + b = (b << 3U) | (b >> 2U); + g = (g << 3U) | (g >> 2U); + r = (r << 3U) | (r >> 2U); + } + + result.set_noclamp_rgba(r, g, b, minimum(alpha, 255U)); + return success; + } + + bool etc_block::unpack_color5(uint32_t& r, uint32_t& g, uint32_t& b, uint16_t packed_color5, uint16_t packed_delta3, bool scaled, uint32_t alpha) + { + color_rgba result; + const bool success = unpack_color5(result, packed_color5, packed_delta3, scaled, alpha); + r = result.r; + g = result.g; + b = result.b; + return success; + } + + uint16_t etc_block::pack_delta3(const color_rgba_i16& color) + { + return pack_delta3(color.r, color.g, color.b); + } + + uint16_t etc_block::pack_delta3(int r, int g, int b) + { + assert((r >= cETC1ColorDeltaMin) && (r <= cETC1ColorDeltaMax)); + assert((g >= cETC1ColorDeltaMin) && (g <= cETC1ColorDeltaMax)); + assert((b >= cETC1ColorDeltaMin) && (b <= cETC1ColorDeltaMax)); + if (r < 0) r += 8; + if (g < 0) g += 8; + if (b < 0) b += 8; + return static_cast(b | (g << 3) | (r << 6)); + } + + color_rgba_i16 etc_block::unpack_delta3(uint16_t packed_delta3) + { + int r = (packed_delta3 >> 6) & 7; + int g = (packed_delta3 >> 3) & 7; + int b = packed_delta3 & 7; + if (r >= 4) r -= 8; + if (g >= 4) g -= 8; + if (b >= 4) b -= 8; + return color_rgba_i16(r, g, b, 255); + } + + void etc_block::unpack_delta3(int& r, int& g, int& b, uint16_t packed_delta3) + { + r = (packed_delta3 >> 6) & 7; + g = (packed_delta3 >> 3) & 7; + b = packed_delta3 & 7; + if (r >= 4) r -= 8; + if (g >= 4) g -= 8; + if (b >= 4) b -= 8; + } + + uint16_t etc_block::pack_color4(const color_rgba& color, bool scaled, uint32_t bias) + { + return pack_color4(color.r, color.g, color.b, scaled, bias); + } + + uint16_t etc_block::pack_color4(uint32_t r, uint32_t g, uint32_t b, bool scaled, uint32_t bias) + { + if (scaled) + { + r = (r * 15U + bias) / 255U; + g = (g * 15U + bias) / 255U; + b = (b * 15U + bias) / 255U; + } + + r = minimum(r, 15U); + g = minimum(g, 15U); + b = minimum(b, 15U); + + return static_cast(b | (g << 4U) | (r << 8U)); + } + + color_rgba etc_block::unpack_color4(uint16_t packed_color4, bool scaled, uint32_t alpha) + { + uint32_t b = packed_color4 & 15U; + uint32_t g = (packed_color4 >> 4U) & 15U; + uint32_t r = (packed_color4 >> 8U) & 15U; + + if (scaled) + { + b = (b << 4U) | b; + g = (g << 4U) | g; + r = (r << 4U) | r; + } + + return color_rgba(cNoClamp, r, g, b, minimum(alpha, 255U)); + } + + void etc_block::unpack_color4(uint32_t& r, uint32_t& g, uint32_t& b, uint16_t packed_color4, bool scaled) + { + color_rgba c(unpack_color4(packed_color4, scaled, 0)); + r = c.r; + g = c.g; + b = c.b; + } + + void etc_block::get_diff_subblock_colors(color_rgba* pDst, uint16_t packed_color5, uint32_t table_idx) + { + assert(table_idx < cETC1IntenModifierValues); + const int *pInten_modifer_table = &g_etc1_inten_tables[table_idx][0]; + + uint32_t r, g, b; + unpack_color5(r, g, b, packed_color5, true); + + const int ir = static_cast(r), ig = static_cast(g), ib = static_cast(b); + + const int y0 = pInten_modifer_table[0]; + pDst[0].set(ir + y0, ig + y0, ib + y0, 255); + + const int y1 = pInten_modifer_table[1]; + pDst[1].set(ir + y1, ig + y1, ib + y1, 255); + + const int y2 = pInten_modifer_table[2]; + pDst[2].set(ir + y2, ig + y2, ib + y2, 255); + + const int y3 = pInten_modifer_table[3]; + pDst[3].set(ir + y3, ig + y3, ib + y3, 255); + } + + bool etc_block::get_diff_subblock_colors(color_rgba* pDst, uint16_t packed_color5, uint16_t packed_delta3, uint32_t table_idx) + { + assert(table_idx < cETC1IntenModifierValues); + const int *pInten_modifer_table = &g_etc1_inten_tables[table_idx][0]; + + uint32_t r, g, b; + bool success = unpack_color5(r, g, b, packed_color5, packed_delta3, true); + + const int ir = static_cast(r), ig = static_cast(g), ib = static_cast(b); + + const int y0 = pInten_modifer_table[0]; + pDst[0].set(ir + y0, ig + y0, ib + y0, 255); + + const int y1 = pInten_modifer_table[1]; + pDst[1].set(ir + y1, ig + y1, ib + y1, 255); + + const int y2 = pInten_modifer_table[2]; + pDst[2].set(ir + y2, ig + y2, ib + y2, 255); + + const int y3 = pInten_modifer_table[3]; + pDst[3].set(ir + y3, ig + y3, ib + y3, 255); + + return success; + } + + void etc_block::get_abs_subblock_colors(color_rgba* pDst, uint16_t packed_color4, uint32_t table_idx) + { + assert(table_idx < cETC1IntenModifierValues); + const int *pInten_modifer_table = &g_etc1_inten_tables[table_idx][0]; + + uint32_t r, g, b; + unpack_color4(r, g, b, packed_color4, true); + + const int ir = static_cast(r), ig = static_cast(g), ib = static_cast(b); + + const int y0 = pInten_modifer_table[0]; + pDst[0].set(ir + y0, ig + y0, ib + y0, 255); + + const int y1 = pInten_modifer_table[1]; + pDst[1].set(ir + y1, ig + y1, ib + y1, 255); + + const int y2 = pInten_modifer_table[2]; + pDst[2].set(ir + y2, ig + y2, ib + y2, 255); + + const int y3 = pInten_modifer_table[3]; + pDst[3].set(ir + y3, ig + y3, ib + y3, 255); + } + + bool unpack_etc1(const etc_block& block, color_rgba *pDst, bool preserve_alpha) + { + const bool diff_flag = block.get_diff_bit(); + const bool flip_flag = block.get_flip_bit(); + const uint32_t table_index0 = block.get_inten_table(0); + const uint32_t table_index1 = block.get_inten_table(1); + + color_rgba subblock_colors0[4]; + color_rgba subblock_colors1[4]; + + if (diff_flag) + { + const uint16_t base_color5 = block.get_base5_color(); + const uint16_t delta_color3 = block.get_delta3_color(); + etc_block::get_diff_subblock_colors(subblock_colors0, base_color5, table_index0); + + if (!etc_block::get_diff_subblock_colors(subblock_colors1, base_color5, delta_color3, table_index1)) + return false; + } + else + { + const uint16_t base_color4_0 = block.get_base4_color(0); + etc_block::get_abs_subblock_colors(subblock_colors0, base_color4_0, table_index0); + + const uint16_t base_color4_1 = block.get_base4_color(1); + etc_block::get_abs_subblock_colors(subblock_colors1, base_color4_1, table_index1); + } + + if (preserve_alpha) + { + if (flip_flag) + { + for (uint32_t y = 0; y < 2; y++) + { + pDst[0].set_rgb(subblock_colors0[block.get_selector(0, y)]); + pDst[1].set_rgb(subblock_colors0[block.get_selector(1, y)]); + pDst[2].set_rgb(subblock_colors0[block.get_selector(2, y)]); + pDst[3].set_rgb(subblock_colors0[block.get_selector(3, y)]); + pDst += 4; + } + + for (uint32_t y = 2; y < 4; y++) + { + pDst[0].set_rgb(subblock_colors1[block.get_selector(0, y)]); + pDst[1].set_rgb(subblock_colors1[block.get_selector(1, y)]); + pDst[2].set_rgb(subblock_colors1[block.get_selector(2, y)]); + pDst[3].set_rgb(subblock_colors1[block.get_selector(3, y)]); + pDst += 4; + } + } + else + { + for (uint32_t y = 0; y < 4; y++) + { + pDst[0].set_rgb(subblock_colors0[block.get_selector(0, y)]); + pDst[1].set_rgb(subblock_colors0[block.get_selector(1, y)]); + pDst[2].set_rgb(subblock_colors1[block.get_selector(2, y)]); + pDst[3].set_rgb(subblock_colors1[block.get_selector(3, y)]); + pDst += 4; + } + } + } + else + { + if (flip_flag) + { + // 0000 + // 0000 + // 1111 + // 1111 + for (uint32_t y = 0; y < 2; y++) + { + pDst[0] = subblock_colors0[block.get_selector(0, y)]; + pDst[1] = subblock_colors0[block.get_selector(1, y)]; + pDst[2] = subblock_colors0[block.get_selector(2, y)]; + pDst[3] = subblock_colors0[block.get_selector(3, y)]; + pDst += 4; + } + + for (uint32_t y = 2; y < 4; y++) + { + pDst[0] = subblock_colors1[block.get_selector(0, y)]; + pDst[1] = subblock_colors1[block.get_selector(1, y)]; + pDst[2] = subblock_colors1[block.get_selector(2, y)]; + pDst[3] = subblock_colors1[block.get_selector(3, y)]; + pDst += 4; + } + } + else + { + // 0011 + // 0011 + // 0011 + // 0011 + for (uint32_t y = 0; y < 4; y++) + { + pDst[0] = subblock_colors0[block.get_selector(0, y)]; + pDst[1] = subblock_colors0[block.get_selector(1, y)]; + pDst[2] = subblock_colors1[block.get_selector(2, y)]; + pDst[3] = subblock_colors1[block.get_selector(3, y)]; + pDst += 4; + } + } + } + + return true; + } + + inline int extend_6_to_8(uint32_t n) + { + return (n << 2) | (n >> 4); + } + + inline int extend_7_to_8(uint32_t n) + { + return (n << 1) | (n >> 6); + } + + inline int extend_4_to_8(uint32_t n) + { + return (n << 4) | n; + } + + uint64_t etc_block::evaluate_etc1_error(const color_rgba* pBlock_pixels, bool perceptual, int subblock_index) const + { + color_rgba unpacked_block[16]; + + unpack_etc1(*this, unpacked_block); + + uint64_t total_error = 0; + + if (subblock_index < 0) + { + for (uint32_t i = 0; i < 16; i++) + total_error += color_distance(perceptual, pBlock_pixels[i], unpacked_block[i], false); + } + else + { + const bool flip_bit = get_flip_bit(); + + for (uint32_t i = 0; i < 8; i++) + { + const uint32_t idx = g_etc1_pixel_indices[flip_bit][subblock_index][i]; + + total_error += color_distance(perceptual, pBlock_pixels[idx], unpacked_block[idx], false); + } + } + + return total_error; + } + + void etc_block::get_subblock_pixels(color_rgba* pPixels, int subblock_index) const + { + if (subblock_index < 0) + unpack_etc1(*this, pPixels); + else + { + color_rgba unpacked_block[16]; + + unpack_etc1(*this, unpacked_block); + + const bool flip_bit = get_flip_bit(); + + for (uint32_t i = 0; i < 8; i++) + { + const uint32_t idx = g_etc1_pixel_indices[flip_bit][subblock_index][i]; + + pPixels[i] = unpacked_block[idx]; + } + } + } + + bool etc1_optimizer::compute() + { + assert(m_pResult->m_pSelectors); + + if (m_pParams->m_pForce_selectors) + { + assert(m_pParams->m_quality >= cETCQualitySlow); + if (m_pParams->m_quality < cETCQualitySlow) + return false; + } + + const uint32_t n = m_pParams->m_num_src_pixels; + + if (m_pParams->m_cluster_fit) + { + if (m_pParams->m_quality == cETCQualityFast) + compute_internal_cluster_fit(4); + else if (m_pParams->m_quality == cETCQualityMedium) + compute_internal_cluster_fit(16); + else if (m_pParams->m_quality == cETCQualitySlow) + compute_internal_cluster_fit(64); + else + compute_internal_cluster_fit(BASISU_ETC1_CLUSTER_FIT_ORDER_TABLE_SIZE); + } + else + compute_internal_neighborhood(m_br, m_bg, m_bb); + + if (!m_best_solution.m_valid) + { + m_pResult->m_error = UINT32_MAX; + return false; + } + + //const uint8_t* pSelectors = &m_best_solution.m_selectors[0]; + const uint8_t* pSelectors = m_pParams->m_pForce_selectors ? m_pParams->m_pForce_selectors : &m_best_solution.m_selectors[0]; + +#if defined(DEBUG) || defined(_DEBUG) + { + // sanity check the returned error + color_rgba block_colors[4]; + m_best_solution.m_coords.get_block_colors(block_colors); + + const color_rgba* pSrc_pixels = m_pParams->m_pSrc_pixels; + uint64_t actual_error = 0; + + bool perceptual; + if (m_pParams->m_quality >= cETCQualityMedium) + perceptual = m_pParams->m_perceptual; + else + perceptual = (m_pParams->m_quality == cETCQualityFast) ? false : m_pParams->m_perceptual; + + for (uint32_t i = 0; i < n; i++) + actual_error += color_distance(perceptual, pSrc_pixels[i], block_colors[pSelectors[i]], false); + + assert(actual_error == m_best_solution.m_error); + } +#endif + + m_pResult->m_error = m_best_solution.m_error; + + m_pResult->m_block_color_unscaled = m_best_solution.m_coords.m_unscaled_color; + m_pResult->m_block_color4 = m_best_solution.m_coords.m_color4; + + m_pResult->m_block_inten_table = m_best_solution.m_coords.m_inten_table; + memcpy(m_pResult->m_pSelectors, pSelectors, n); + m_pResult->m_n = n; + + return true; + } + + void etc1_optimizer::refine_solution(uint32_t max_refinement_trials) + { + // Now we have the input block, the avg. color of the input pixels, a set of trial selector indices, and the block color+intensity index. + // Now, for each component, attempt to refine the current solution by solving a simple linear equation. For example, for 4 colors: + // The goal is: + // pixel0 - (block_color+inten_table[selector0]) + pixel1 - (block_color+inten_table[selector1]) + pixel2 - (block_color+inten_table[selector2]) + pixel3 - (block_color+inten_table[selector3]) = 0 + // Rearranging this: + // (pixel0 + pixel1 + pixel2 + pixel3) - (block_color+inten_table[selector0]) - (block_color+inten_table[selector1]) - (block_color+inten_table[selector2]) - (block_color+inten_table[selector3]) = 0 + // (pixel0 + pixel1 + pixel2 + pixel3) - block_color - inten_table[selector0] - block_color-inten_table[selector1] - block_color-inten_table[selector2] - block_color-inten_table[selector3] = 0 + // (pixel0 + pixel1 + pixel2 + pixel3) - 4*block_color - inten_table[selector0] - inten_table[selector1] - inten_table[selector2] - inten_table[selector3] = 0 + // (pixel0 + pixel1 + pixel2 + pixel3) - 4*block_color - (inten_table[selector0] + inten_table[selector1] + inten_table[selector2] + inten_table[selector3]) = 0 + // (pixel0 + pixel1 + pixel2 + pixel3)/4 - block_color - (inten_table[selector0] + inten_table[selector1] + inten_table[selector2] + inten_table[selector3])/4 = 0 + // block_color = (pixel0 + pixel1 + pixel2 + pixel3)/4 - (inten_table[selector0] + inten_table[selector1] + inten_table[selector2] + inten_table[selector3])/4 + // So what this means: + // optimal_block_color = avg_input - avg_inten_delta + // So the optimal block color can be computed by taking the average block color and subtracting the current average of the intensity delta. + // Unfortunately, optimal_block_color must then be quantized to 555 or 444 so it's not always possible to improve matters using this formula. + // Also, the above formula is for unclamped intensity deltas. The actual implementation takes into account clamping. + + const uint32_t n = m_pParams->m_num_src_pixels; + + for (uint32_t refinement_trial = 0; refinement_trial < max_refinement_trials; refinement_trial++) + { + const uint8_t* pSelectors = &m_best_solution.m_selectors[0]; + const int* pInten_table = g_etc1_inten_tables[m_best_solution.m_coords.m_inten_table]; + + int delta_sum_r = 0, delta_sum_g = 0, delta_sum_b = 0; + const color_rgba base_color(m_best_solution.m_coords.get_scaled_color()); + for (uint32_t r = 0; r < n; r++) + { + const uint32_t s = *pSelectors++; + const int yd_temp = pInten_table[s]; + // Compute actual delta being applied to each pixel, taking into account clamping. + delta_sum_r += clamp(base_color.r + yd_temp, 0, 255) - base_color.r; + delta_sum_g += clamp(base_color.g + yd_temp, 0, 255) - base_color.g; + delta_sum_b += clamp(base_color.b + yd_temp, 0, 255) - base_color.b; + } + + if ((!delta_sum_r) && (!delta_sum_g) && (!delta_sum_b)) + break; + + const float avg_delta_r_f = static_cast(delta_sum_r) / n; + const float avg_delta_g_f = static_cast(delta_sum_g) / n; + const float avg_delta_b_f = static_cast(delta_sum_b) / n; + const int br1 = clamp(static_cast((m_avg_color[0] - avg_delta_r_f) * m_limit / 255.0f + .5f), 0, m_limit); + const int bg1 = clamp(static_cast((m_avg_color[1] - avg_delta_g_f) * m_limit / 255.0f + .5f), 0, m_limit); + const int bb1 = clamp(static_cast((m_avg_color[2] - avg_delta_b_f) * m_limit / 255.0f + .5f), 0, m_limit); + +#if BASISU_DEBUG_ETC_ENCODER_DEEPER + printf("Refinement trial %u, avg_delta %f %f %f\n", refinement_trial, avg_delta_r_f, avg_delta_g_f, avg_delta_b_f); +#endif + + if (!evaluate_solution(etc1_solution_coordinates(br1, bg1, bb1, 0, m_pParams->m_use_color4), m_trial_solution, &m_best_solution)) + break; + + } // refinement_trial + } + + void etc1_optimizer::compute_internal_neighborhood(int scan_r, int scan_g, int scan_b) + { + if (m_best_solution.m_error == 0) + return; + + //const uint32_t n = m_pParams->m_num_src_pixels; + const int scan_delta_size = m_pParams->m_scan_delta_size; + + // Scan through a subset of the 3D lattice centered around the avg block color trying each 3D (555 or 444) lattice point as a potential block color. + // Each time a better solution is found try to refine the current solution's block color based of the current selectors and intensity table index. + for (int zdi = 0; zdi < scan_delta_size; zdi++) + { + const int zd = m_pParams->m_pScan_deltas[zdi]; + const int mbb = scan_b + zd; + if (mbb < 0) continue; else if (mbb > m_limit) break; + + for (int ydi = 0; ydi < scan_delta_size; ydi++) + { + const int yd = m_pParams->m_pScan_deltas[ydi]; + const int mbg = scan_g + yd; + if (mbg < 0) continue; else if (mbg > m_limit) break; + + for (int xdi = 0; xdi < scan_delta_size; xdi++) + { + const int xd = m_pParams->m_pScan_deltas[xdi]; + const int mbr = scan_r + xd; + if (mbr < 0) continue; else if (mbr > m_limit) break; + + etc1_solution_coordinates coords(mbr, mbg, mbb, 0, m_pParams->m_use_color4); + + if (!evaluate_solution(coords, m_trial_solution, &m_best_solution)) + continue; + + if (m_pParams->m_refinement) + { + refine_solution((m_pParams->m_quality == cETCQualityFast) ? 2 : (((xd | yd | zd) == 0) ? 4 : 2)); + } + + } // xdi + } // ydi + } // zdi + } + + void etc1_optimizer::compute_internal_cluster_fit(uint32_t total_perms_to_try) + { + if ((!m_best_solution.m_valid) || ((m_br != m_best_solution.m_coords.m_unscaled_color.r) || (m_bg != m_best_solution.m_coords.m_unscaled_color.g) || (m_bb != m_best_solution.m_coords.m_unscaled_color.b))) + { + evaluate_solution(etc1_solution_coordinates(m_br, m_bg, m_bb, 0, m_pParams->m_use_color4), m_trial_solution, &m_best_solution); + } + + if ((m_best_solution.m_error == 0) || (!m_best_solution.m_valid)) + return; + + for (uint32_t i = 0; i < total_perms_to_try; i++) + { + int delta_sum_r = 0, delta_sum_g = 0, delta_sum_b = 0; + + const int *pInten_table = g_etc1_inten_tables[m_best_solution.m_coords.m_inten_table]; + const color_rgba base_color(m_best_solution.m_coords.get_scaled_color()); + + const uint8_t *pNum_selectors = g_cluster_fit_order_tab[i].m_v; + + for (uint32_t q = 0; q < 4; q++) + { + const int yd_temp = pInten_table[q]; + + delta_sum_r += pNum_selectors[q] * (clamp(base_color.r + yd_temp, 0, 255) - base_color.r); + delta_sum_g += pNum_selectors[q] * (clamp(base_color.g + yd_temp, 0, 255) - base_color.g); + delta_sum_b += pNum_selectors[q] * (clamp(base_color.b + yd_temp, 0, 255) - base_color.b); + } + + if ((!delta_sum_r) && (!delta_sum_g) && (!delta_sum_b)) + continue; + + const float avg_delta_r_f = static_cast(delta_sum_r) / 8; + const float avg_delta_g_f = static_cast(delta_sum_g) / 8; + const float avg_delta_b_f = static_cast(delta_sum_b) / 8; + + const int br1 = clamp(static_cast((m_avg_color[0] - avg_delta_r_f) * m_limit / 255.0f + .5f), 0, m_limit); + const int bg1 = clamp(static_cast((m_avg_color[1] - avg_delta_g_f) * m_limit / 255.0f + .5f), 0, m_limit); + const int bb1 = clamp(static_cast((m_avg_color[2] - avg_delta_b_f) * m_limit / 255.0f + .5f), 0, m_limit); + +#if BASISU_DEBUG_ETC_ENCODER_DEEPER + printf("Second refinement trial %u, avg_delta %f %f %f\n", i, avg_delta_r_f, avg_delta_g_f, avg_delta_b_f); +#endif + + evaluate_solution(etc1_solution_coordinates(br1, bg1, bb1, 0, m_pParams->m_use_color4), m_trial_solution, &m_best_solution); + + if (m_best_solution.m_error == 0) + break; + } + } + + void etc1_optimizer::init(const params& params, results& result) + { + m_pParams = ¶ms; + m_pResult = &result; + + const uint32_t n = m_pParams->m_num_src_pixels; + + m_selectors.resize(n); + m_best_selectors.resize(n); + m_temp_selectors.resize(n); + m_trial_solution.m_selectors.resize(n); + m_best_solution.m_selectors.resize(n); + + m_limit = m_pParams->m_use_color4 ? 15 : 31; + + vec3F avg_color(0.0f); + + m_luma.resize(n); + m_sorted_luma_indices.resize(n); + m_sorted_luma.resize(n); + + int min_r = 255, min_g = 255, min_b = 255; + int max_r = 0, max_g = 0, max_b = 0; + + for (uint32_t i = 0; i < n; i++) + { + const color_rgba& c = m_pParams->m_pSrc_pixels[i]; + + min_r = basisu::minimum(min_r, c.r); + min_g = basisu::minimum(min_g, c.g); + min_b = basisu::minimum(min_b, c.b); + + max_r = basisu::maximum(max_r, c.r); + max_g = basisu::maximum(max_g, c.g); + max_b = basisu::maximum(max_b, c.b); + + const vec3F fc(c.r, c.g, c.b); + + avg_color += fc; + + m_luma[i] = static_cast(c.r + c.g + c.b); + m_sorted_luma_indices[i] = i; + } + avg_color /= static_cast(n); + m_avg_color = avg_color; + m_max_comp_spread = basisu::maximum(basisu::maximum(max_r - min_r, max_g - min_g), max_b - min_b); + + m_br = clamp(static_cast(m_avg_color[0] * m_limit / 255.0f + .5f), 0, m_limit); + m_bg = clamp(static_cast(m_avg_color[1] * m_limit / 255.0f + .5f), 0, m_limit); + m_bb = clamp(static_cast(m_avg_color[2] * m_limit / 255.0f + .5f), 0, m_limit); + +#if BASISU_DEBUG_ETC_ENCODER_DEEPER + printf("Avg block color: %u %u %u\n", m_br, m_bg, m_bb); +#endif + + if (m_pParams->m_quality == cETCQualityFast) + { + indirect_sort(n, &m_sorted_luma_indices[0], &m_luma[0]); + + m_pSorted_luma = &m_sorted_luma[0]; + m_pSorted_luma_indices = &m_sorted_luma_indices[0]; + + for (uint32_t i = 0; i < n; i++) + m_pSorted_luma[i] = m_luma[m_pSorted_luma_indices[i]]; + } + + m_best_solution.m_coords.clear(); + m_best_solution.m_valid = false; + m_best_solution.m_error = UINT64_MAX; + + clear_obj(m_solutions_tried); + } + + // Return false if we've probably already tried this solution, true if we have definitely not. + bool etc1_optimizer::check_for_redundant_solution(const etc1_solution_coordinates& coords) + { + // Hash first 3 bytes of color (RGB) + uint32_t kh = hash_hsieh((uint8_t*)&coords.m_unscaled_color.r, 3); + + uint32_t h0 = kh & cSolutionsTriedHashMask; + uint32_t h1 = (kh >> cSolutionsTriedHashBits) & cSolutionsTriedHashMask; + + // Simple Bloom filter lookup with k=2 + if ( ((m_solutions_tried[h0 >> 3] & (1 << (h0 & 7))) != 0) && + ((m_solutions_tried[h1 >> 3] & (1 << (h1 & 7))) != 0) ) + return false; + + m_solutions_tried[h0 >> 3] |= (1 << (h0 & 7)); + m_solutions_tried[h1 >> 3] |= (1 << (h1 & 7)); + + return true; + } + + static uint8_t g_eval_dist_tables[8][256] = + { + // 99% threshold + { 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,}, + { 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+ { + const int dr = (int)coords.m_unscaled_color.r - (int)m_pParams->m_base_color5.r; + const int dg = (int)coords.m_unscaled_color.g - (int)m_pParams->m_base_color5.g; + const int db = (int)coords.m_unscaled_color.b - (int)m_pParams->m_base_color5.b; + + if ((minimum(dr, dg, db) < cETC1ColorDeltaMin) || (maximum(dr, dg, db) > cETC1ColorDeltaMax)) + { +#if BASISU_DEBUG_ETC_ENCODER_DEEPER + printf("Eval failed due to constraint from %u %u %u\n", m_pParams->m_base_color5.r, m_pParams->m_base_color5.g, m_pParams->m_base_color5.b); +#endif + return false; + } + } + + const color_rgba base_color(coords.get_scaled_color()); + + const uint32_t n = m_pParams->m_num_src_pixels; + assert(trial_solution.m_selectors.size() == n); + + trial_solution.m_error = INT64_MAX; + + const uint8_t *pSelectors_to_use = m_pParams->m_pForce_selectors; + + for (uint32_t inten_table = 0; inten_table < cETC1IntenModifierValues; inten_table++) + { + if (m_pParams->m_quality <= cETCQualityMedium) + { + if (!g_eval_dist_tables[inten_table][m_max_comp_spread]) + continue; + } +#if 0 + if (m_pParams->m_quality <= cETCQualityMedium) + { + // For tables 5-7, if the max component spread falls within certain ranges, skip the inten table. Statistically they are extremely unlikely to result in lower error. + if (inten_table == 7) + { + if (m_max_comp_spread < 42) + continue; + } + else if (inten_table == 6) + { + if ((m_max_comp_spread >= 12) && (m_max_comp_spread <= 31)) + continue; + } + else if (inten_table == 5) + { + if ((m_max_comp_spread >= 13) && (m_max_comp_spread <= 21)) + continue; + } + } +#endif + + const int* pInten_table = g_etc1_inten_tables[inten_table]; + + color_rgba block_colors[4]; + for (uint32_t s = 0; s < 4; s++) + { + const int yd = pInten_table[s]; + block_colors[s].set(base_color.r + yd, base_color.g + yd, base_color.b + yd, 255); + } + + uint64_t total_error = 0; + + const color_rgba* pSrc_pixels = m_pParams->m_pSrc_pixels; + + if (!g_cpu_supports_sse41) + { + for (uint32_t c = 0; c < n; c++) + { + const color_rgba& src_pixel = *pSrc_pixels++; + + uint32_t best_selector_index = 0; + uint32_t best_error = 0; + + if (pSelectors_to_use) + { + best_selector_index = pSelectors_to_use[c]; + best_error = color_distance(m_pParams->m_perceptual, src_pixel, block_colors[best_selector_index], false); + } + else + { + best_error = color_distance(m_pParams->m_perceptual, src_pixel, block_colors[0], false); + + uint32_t trial_error = color_distance(m_pParams->m_perceptual, src_pixel, block_colors[1], false); + if (trial_error < best_error) + { + best_error = trial_error; + best_selector_index = 1; + } + + trial_error = color_distance(m_pParams->m_perceptual, src_pixel, block_colors[2], false); + if (trial_error < best_error) + { + best_error = trial_error; + best_selector_index = 2; + } + + trial_error = color_distance(m_pParams->m_perceptual, src_pixel, block_colors[3], false); + if (trial_error < best_error) + { + best_error = trial_error; + best_selector_index = 3; + } + } + + m_temp_selectors[c] = static_cast(best_selector_index); + + total_error += best_error; + if (total_error >= trial_solution.m_error) + break; + } + } + else + { +#if BASISU_SUPPORT_SSE + if (pSelectors_to_use) + { + if (m_pParams->m_perceptual) + perceptual_distance_rgb_4_N_sse41((int64_t*)&total_error, pSelectors_to_use, block_colors, pSrc_pixels, n, trial_solution.m_error); + else + linear_distance_rgb_4_N_sse41((int64_t*)&total_error, pSelectors_to_use, block_colors, pSrc_pixels, n, trial_solution.m_error); + } + else + { + if (m_pParams->m_perceptual) + find_selectors_perceptual_rgb_4_N_sse41((int64_t*)&total_error, &m_temp_selectors[0], block_colors, pSrc_pixels, n, trial_solution.m_error); + else + find_selectors_linear_rgb_4_N_sse41((int64_t*)&total_error, &m_temp_selectors[0], block_colors, pSrc_pixels, n, trial_solution.m_error); + } +#endif + } + + if (total_error < trial_solution.m_error) + { + trial_solution.m_error = total_error; + trial_solution.m_coords.m_inten_table = inten_table; + trial_solution.m_selectors.swap(m_temp_selectors); + trial_solution.m_valid = true; + } + } + trial_solution.m_coords.m_unscaled_color = coords.m_unscaled_color; + trial_solution.m_coords.m_color4 = m_pParams->m_use_color4; + +#if BASISU_DEBUG_ETC_ENCODER_DEEPER + printf("Eval done: %u error: %I64u best error so far: %I64u\n", (trial_solution.m_error < pBest_solution->m_error), trial_solution.m_error, pBest_solution->m_error); +#endif + + bool success = false; + if (pBest_solution) + { + if (trial_solution.m_error < pBest_solution->m_error) + { + *pBest_solution = trial_solution; + success = true; + } + } + + return success; + } + + bool etc1_optimizer::evaluate_solution_fast(const etc1_solution_coordinates& coords, potential_solution& trial_solution, potential_solution* pBest_solution) + { + if (!check_for_redundant_solution(coords)) + return false; + +#if BASISU_DEBUG_ETC_ENCODER_DEEPER + printf("Eval solution fast: %u %u %u\n", coords.m_unscaled_color.r, coords.m_unscaled_color.g, coords.m_unscaled_color.b); +#endif + + if (m_pParams->m_constrain_against_base_color5) + { + const int dr = (int)coords.m_unscaled_color.r - (int)m_pParams->m_base_color5.r; + const int dg = (int)coords.m_unscaled_color.g - (int)m_pParams->m_base_color5.g; + const int db = (int)coords.m_unscaled_color.b - (int)m_pParams->m_base_color5.b; + + if ((minimum(dr, dg, db) < cETC1ColorDeltaMin) || (maximum(dr, dg, db) > cETC1ColorDeltaMax)) + { + trial_solution.m_valid = false; + +#if BASISU_DEBUG_ETC_ENCODER_DEEPER + printf("Eval failed due to constraint from %u %u %u\n", m_pParams->m_base_color5.r, m_pParams->m_base_color5.g, m_pParams->m_base_color5.b); +#endif + return false; + } + } + + const color_rgba base_color(coords.get_scaled_color()); + + const uint32_t n = m_pParams->m_num_src_pixels; + assert(trial_solution.m_selectors.size() == n); + + trial_solution.m_error = UINT64_MAX; + + const bool perceptual = (m_pParams->m_quality == cETCQualityFast) ? false : m_pParams->m_perceptual; + + for (int inten_table = cETC1IntenModifierValues - 1; inten_table >= 0; --inten_table) + { + const int* pInten_table = g_etc1_inten_tables[inten_table]; + + uint32_t block_inten[4]; + color_rgba block_colors[4]; + for (uint32_t s = 0; s < 4; s++) + { + const int yd = pInten_table[s]; + color_rgba block_color(base_color.r + yd, base_color.g + yd, base_color.b + yd, 255); + block_colors[s] = block_color; + block_inten[s] = block_color.r + block_color.g + block_color.b; + } + + // evaluate_solution_fast() enforces/assumes a total ordering of the input colors along the intensity (1,1,1) axis to more quickly classify the inputs to selectors. + // The inputs colors have been presorted along the projection onto this axis, and ETC1 block colors are always ordered along the intensity axis, so this classification is fast. + // 0 1 2 3 + // 01 12 23 + const uint32_t block_inten_midpoints[3] = { block_inten[0] + block_inten[1], block_inten[1] + block_inten[2], block_inten[2] + block_inten[3] }; + + uint64_t total_error = 0; + const color_rgba* pSrc_pixels = m_pParams->m_pSrc_pixels; + + if (perceptual) + { + if ((m_pSorted_luma[n - 1] * 2) < block_inten_midpoints[0]) + { + if (block_inten[0] > m_pSorted_luma[n - 1]) + { + const uint32_t min_error = iabs((int)block_inten[0] - (int)m_pSorted_luma[n - 1]); + if (min_error >= trial_solution.m_error) + continue; + } + + memset(&m_temp_selectors[0], 0, n); + + for (uint32_t c = 0; c < n; c++) + total_error += color_distance(true, block_colors[0], pSrc_pixels[c], false); + } + else if ((m_pSorted_luma[0] * 2) >= block_inten_midpoints[2]) + { + if (m_pSorted_luma[0] > block_inten[3]) + { + const uint32_t min_error = iabs((int)m_pSorted_luma[0] - (int)block_inten[3]); + if (min_error >= trial_solution.m_error) + continue; + } + + memset(&m_temp_selectors[0], 3, n); + + for (uint32_t c = 0; c < n; c++) + total_error += color_distance(true, block_colors[3], pSrc_pixels[c], false); + } + else + { + if (!g_cpu_supports_sse41) + { + uint32_t cur_selector = 0, c; + for (c = 0; c < n; c++) + { + const uint32_t y = m_pSorted_luma[c]; + while ((y * 2) >= block_inten_midpoints[cur_selector]) + if (++cur_selector > 2) + goto done; + const uint32_t sorted_pixel_index = m_pSorted_luma_indices[c]; + m_temp_selectors[sorted_pixel_index] = static_cast(cur_selector); + total_error += color_distance(true, block_colors[cur_selector], pSrc_pixels[sorted_pixel_index], false); + } + done: + while (c < n) + { + const uint32_t sorted_pixel_index = m_pSorted_luma_indices[c]; + m_temp_selectors[sorted_pixel_index] = 3; + total_error += color_distance(true, block_colors[3], pSrc_pixels[sorted_pixel_index], false); + ++c; + } + } + else + { +#if BASISU_SUPPORT_SSE + uint32_t cur_selector = 0, c; + + for (c = 0; c < n; c++) + { + const uint32_t y = m_pSorted_luma[c]; + while ((y * 2) >= block_inten_midpoints[cur_selector]) + { + if (++cur_selector > 2) + goto done3; + } + const uint32_t sorted_pixel_index = m_pSorted_luma_indices[c]; + m_temp_selectors[sorted_pixel_index] = static_cast(cur_selector); + } + done3: + + while (c < n) + { + const uint32_t sorted_pixel_index = m_pSorted_luma_indices[c]; + m_temp_selectors[sorted_pixel_index] = 3; + ++c; + } + + int64_t block_error; + perceptual_distance_rgb_4_N_sse41(&block_error, &m_temp_selectors[0], block_colors, pSrc_pixels, n, INT64_MAX); + total_error += block_error; +#endif + } + } + } + else + { + if ((m_pSorted_luma[n - 1] * 2) < block_inten_midpoints[0]) + { + if (block_inten[0] > m_pSorted_luma[n - 1]) + { + const uint32_t min_error = iabs((int)block_inten[0] - (int)m_pSorted_luma[n - 1]); + if (min_error >= trial_solution.m_error) + continue; + } + + memset(&m_temp_selectors[0], 0, n); + + for (uint32_t c = 0; c < n; c++) + total_error += color_distance(block_colors[0], pSrc_pixels[c], false); + } + else if ((m_pSorted_luma[0] * 2) >= block_inten_midpoints[2]) + { + if (m_pSorted_luma[0] > block_inten[3]) + { + const uint32_t min_error = iabs((int)m_pSorted_luma[0] - (int)block_inten[3]); + if (min_error >= trial_solution.m_error) + continue; + } + + memset(&m_temp_selectors[0], 3, n); + + for (uint32_t c = 0; c < n; c++) + total_error += color_distance(block_colors[3], pSrc_pixels[c], false); + } + else + { + uint32_t cur_selector = 0, c; + for (c = 0; c < n; c++) + { + const uint32_t y = m_pSorted_luma[c]; + while ((y * 2) >= block_inten_midpoints[cur_selector]) + if (++cur_selector > 2) + goto done2; + const uint32_t sorted_pixel_index = m_pSorted_luma_indices[c]; + m_temp_selectors[sorted_pixel_index] = static_cast(cur_selector); + total_error += color_distance(block_colors[cur_selector], pSrc_pixels[sorted_pixel_index], false); + } + done2: + while (c < n) + { + const uint32_t sorted_pixel_index = m_pSorted_luma_indices[c]; + m_temp_selectors[sorted_pixel_index] = 3; + total_error += color_distance(block_colors[3], pSrc_pixels[sorted_pixel_index], false); + ++c; + } + } + } + + if (total_error < trial_solution.m_error) + { + trial_solution.m_error = total_error; + trial_solution.m_coords.m_inten_table = inten_table; + trial_solution.m_selectors.swap(m_temp_selectors); + trial_solution.m_valid = true; + if (!total_error) + break; + } + } + trial_solution.m_coords.m_unscaled_color = coords.m_unscaled_color; + trial_solution.m_coords.m_color4 = m_pParams->m_use_color4; + +#if BASISU_DEBUG_ETC_ENCODER_DEEPER + printf("Eval done: %u error: %I64u best error so far: %I64u\n", (trial_solution.m_error < pBest_solution->m_error), trial_solution.m_error, pBest_solution->m_error); +#endif + + bool success = false; + if (pBest_solution) + { + if (trial_solution.m_error < pBest_solution->m_error) + { + *pBest_solution = trial_solution; + success = true; + } + } + + return success; + } + + uint64_t pack_eac_a8(pack_eac_a8_results& results, const uint8_t* pPixels, uint32_t num_pixels, uint32_t base_search_rad, uint32_t mul_search_rad, uint32_t table_mask) + { + results.m_selectors.resize(num_pixels); + results.m_selectors_temp.resize(num_pixels); + + uint32_t min_alpha = 255, max_alpha = 0; + for (uint32_t i = 0; i < num_pixels; i++) + { + const uint32_t a = pPixels[i]; + if (a < min_alpha) min_alpha = a; + if (a > max_alpha) max_alpha = a; + } + + if (min_alpha == max_alpha) + { + results.m_base = min_alpha; + results.m_table = 13; + results.m_multiplier = 1; + for (uint32_t i = 0; i < num_pixels; i++) + results.m_selectors[i] = 4; + return 0; + } + + const uint32_t alpha_range = max_alpha - min_alpha; + + uint64_t best_err = UINT64_MAX; + + for (uint32_t table = 0; table < 16; table++) + { + if ((table_mask & (1U << table)) == 0) + continue; + + const float range = (float)(g_etc2_eac_tables[table][ETC2_EAC_MAX_VALUE_SELECTOR] - g_etc2_eac_tables[table][ETC2_EAC_MIN_VALUE_SELECTOR]); + const int center = (int)roundf(lerp((float)min_alpha, (float)max_alpha, (float)(0 - g_etc2_eac_tables[table][ETC2_EAC_MIN_VALUE_SELECTOR]) / range)); + + const int base_min = clamp255(center - base_search_rad); + const int base_max = clamp255(center + base_search_rad); + + const int mul = (int)roundf(alpha_range / range); + const int mul_low = clamp(mul - mul_search_rad, 1, 15); + const int mul_high = clamp(mul + mul_search_rad, 1, 15); + + for (int base = base_min; base <= base_max; base++) + { + for (int multiplier = mul_low; multiplier <= mul_high; multiplier++) + { + uint64_t total_err = 0; + + for (uint32_t i = 0; i < num_pixels; i++) + { + const int a = pPixels[i]; + + uint32_t best_s_err = UINT32_MAX; + uint32_t best_s = 0; + for (uint32_t s = 0; s < 8; s++) + { + const int v = clamp255((int)multiplier * g_etc2_eac_tables[table][s] + (int)base); + + uint32_t err = iabs(a - v); + if (err < best_s_err) + { + best_s_err = err; + best_s = s; + } + } + + results.m_selectors_temp[i] = static_cast(best_s); + + total_err += best_s_err * best_s_err; + if (total_err >= best_err) + break; + } + + if (total_err < best_err) + { + best_err = total_err; + results.m_base = base; + results.m_multiplier = multiplier; + results.m_table = table; + results.m_selectors.swap(results.m_selectors_temp); + if (!best_err) + return best_err; + } + + } // table + + } // multiplier + + } // base + + return best_err; + } + + void pack_eac_a8(eac_a8_block* pBlock, const uint8_t* pPixels, uint32_t base_search_rad, uint32_t mul_search_rad, uint32_t table_mask) + { + pack_eac_a8_results results; + pack_eac_a8(results, pPixels, 16, base_search_rad, mul_search_rad, table_mask); + + pBlock->m_base = results.m_base; + pBlock->m_multiplier = results.m_multiplier; + pBlock->m_table = results.m_table; + for (uint32_t y = 0; y < 4; y++) + for (uint32_t x = 0; x < 4; x++) + pBlock->set_selector(x, y, results.m_selectors[x + y * 4]); + } + +} // namespace basisu -- cgit v1.2.3