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diff --git a/thirdparty/basis_universal/encoder/basisu_etc.h b/thirdparty/basis_universal/encoder/basisu_etc.h
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+++ b/thirdparty/basis_universal/encoder/basisu_etc.h
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+// basis_etc.h
+// 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.
+#pragma once
+#include "../transcoder/basisu.h"
+#include "basisu_enc.h"
+
+namespace basisu
+{
+ enum etc_constants
+ {
+ cETC1BytesPerBlock = 8U,
+
+ cETC1SelectorBits = 2U,
+ cETC1SelectorValues = 1U << cETC1SelectorBits,
+ cETC1SelectorMask = cETC1SelectorValues - 1U,
+
+ cETC1BlockShift = 2U,
+ cETC1BlockSize = 1U << cETC1BlockShift,
+
+ cETC1LSBSelectorIndicesBitOffset = 0,
+ cETC1MSBSelectorIndicesBitOffset = 16,
+
+ cETC1FlipBitOffset = 32,
+ cETC1DiffBitOffset = 33,
+
+ cETC1IntenModifierNumBits = 3,
+ cETC1IntenModifierValues = 1 << cETC1IntenModifierNumBits,
+ cETC1RightIntenModifierTableBitOffset = 34,
+ cETC1LeftIntenModifierTableBitOffset = 37,
+
+ // Base+Delta encoding (5 bit bases, 3 bit delta)
+ cETC1BaseColorCompNumBits = 5,
+ cETC1BaseColorCompMax = 1 << cETC1BaseColorCompNumBits,
+
+ cETC1DeltaColorCompNumBits = 3,
+ cETC1DeltaColorComp = 1 << cETC1DeltaColorCompNumBits,
+ cETC1DeltaColorCompMax = 1 << cETC1DeltaColorCompNumBits,
+
+ cETC1BaseColor5RBitOffset = 59,
+ cETC1BaseColor5GBitOffset = 51,
+ cETC1BaseColor5BBitOffset = 43,
+
+ cETC1DeltaColor3RBitOffset = 56,
+ cETC1DeltaColor3GBitOffset = 48,
+ cETC1DeltaColor3BBitOffset = 40,
+
+ // Absolute (non-delta) encoding (two 4-bit per component bases)
+ cETC1AbsColorCompNumBits = 4,
+ cETC1AbsColorCompMax = 1 << cETC1AbsColorCompNumBits,
+
+ cETC1AbsColor4R1BitOffset = 60,
+ cETC1AbsColor4G1BitOffset = 52,
+ cETC1AbsColor4B1BitOffset = 44,
+
+ cETC1AbsColor4R2BitOffset = 56,
+ cETC1AbsColor4G2BitOffset = 48,
+ cETC1AbsColor4B2BitOffset = 40,
+
+ cETC1ColorDeltaMin = -4,
+ cETC1ColorDeltaMax = 3,
+
+ // Delta3:
+ // 0 1 2 3 4 5 6 7
+ // 000 001 010 011 100 101 110 111
+ // 0 1 2 3 -4 -3 -2 -1
+ };
+
+ extern const int g_etc1_inten_tables[cETC1IntenModifierValues][cETC1SelectorValues];
+ extern const uint8_t g_etc1_to_selector_index[cETC1SelectorValues];
+ extern const uint8_t g_selector_index_to_etc1[cETC1SelectorValues];
+
+ struct etc_coord2
+ {
+ uint8_t m_x, m_y;
+ };
+ extern const etc_coord2 g_etc1_pixel_coords[2][2][8]; // [flipped][subblock][subblock_pixel]
+ extern const uint32_t g_etc1_pixel_indices[2][2][8]; // [flipped][subblock][subblock_pixel]
+
+ struct etc_block
+ {
+ // big endian uint64:
+ // bit ofs: 56 48 40 32 24 16 8 0
+ // byte ofs: b0, b1, b2, b3, b4, b5, b6, b7
+ union
+ {
+ uint64_t m_uint64;
+
+ uint8_t m_bytes[8];
+ };
+
+ inline void clear()
+ {
+ assert(sizeof(*this) == 8);
+ clear_obj(*this);
+ }
+
+ inline uint64_t get_all_bits() const
+ {
+ return read_be64(&m_uint64);
+ }
+
+ inline uint32_t get_general_bits(uint32_t ofs, uint32_t num) const
+ {
+ assert((ofs + num) <= 64U);
+ assert(num && (num < 32U));
+ return (uint32_t)(read_be64(&m_uint64) >> ofs) & ((1UL << num) - 1UL);
+ }
+
+ inline void set_general_bits(uint32_t ofs, uint32_t num, uint32_t bits)
+ {
+ assert((ofs + num) <= 64U);
+ assert(num && (num < 32U));
+
+ uint64_t x = read_be64(&m_uint64);
+ uint64_t msk = ((1ULL << static_cast<uint64_t>(num)) - 1ULL) << static_cast<uint64_t>(ofs);
+ x &= ~msk;
+ x |= (static_cast<uint64_t>(bits) << static_cast<uint64_t>(ofs));
+ write_be64(&m_uint64, x);
+ }
+
+ inline uint32_t get_byte_bits(uint32_t ofs, uint32_t num) const
+ {
+ assert((ofs + num) <= 64U);
+ assert(num && (num <= 8U));
+ assert((ofs >> 3) == ((ofs + num - 1) >> 3));
+ const uint32_t byte_ofs = 7 - (ofs >> 3);
+ const uint32_t byte_bit_ofs = ofs & 7;
+ return (m_bytes[byte_ofs] >> byte_bit_ofs) & ((1 << num) - 1);
+ }
+
+ inline void set_byte_bits(uint32_t ofs, uint32_t num, uint32_t bits)
+ {
+ assert((ofs + num) <= 64U);
+ assert(num && (num < 32U));
+ assert((ofs >> 3) == ((ofs + num - 1) >> 3));
+ assert(bits < (1U << num));
+ const uint32_t byte_ofs = 7 - (ofs >> 3);
+ const uint32_t byte_bit_ofs = ofs & 7;
+ const uint32_t mask = (1 << num) - 1;
+ m_bytes[byte_ofs] &= ~(mask << byte_bit_ofs);
+ m_bytes[byte_ofs] |= (bits << byte_bit_ofs);
+ }
+
+ // false = left/right subblocks
+ // true = upper/lower subblocks
+ inline bool get_flip_bit() const
+ {
+ return (m_bytes[3] & 1) != 0;
+ }
+
+ inline void set_flip_bit(bool flip)
+ {
+ m_bytes[3] &= ~1;
+ m_bytes[3] |= static_cast<uint8_t>(flip);
+ }
+
+ inline bool get_diff_bit() const
+ {
+ return (m_bytes[3] & 2) != 0;
+ }
+
+ inline void set_diff_bit(bool diff)
+ {
+ m_bytes[3] &= ~2;
+ m_bytes[3] |= (static_cast<uint32_t>(diff) << 1);
+ }
+
+ // Returns intensity modifier table (0-7) used by subblock subblock_id.
+ // subblock_id=0 left/top (CW 1), 1=right/bottom (CW 2)
+ inline uint32_t get_inten_table(uint32_t subblock_id) const
+ {
+ assert(subblock_id < 2);
+ const uint32_t ofs = subblock_id ? 2 : 5;
+ return (m_bytes[3] >> ofs) & 7;
+ }
+
+ // Sets intensity modifier table (0-7) used by subblock subblock_id (0 or 1)
+ inline void set_inten_table(uint32_t subblock_id, uint32_t t)
+ {
+ assert(subblock_id < 2);
+ assert(t < 8);
+ const uint32_t ofs = subblock_id ? 2 : 5;
+ m_bytes[3] &= ~(7 << ofs);
+ m_bytes[3] |= (t << ofs);
+ }
+
+ inline void set_inten_tables_etc1s(uint32_t t)
+ {
+ set_inten_table(0, t);
+ set_inten_table(1, t);
+ }
+
+ inline bool is_etc1s() const
+ {
+ if (get_inten_table(0) != get_inten_table(1))
+ return false;
+
+ if (get_diff_bit())
+ {
+ if (get_delta3_color() != 0)
+ return false;
+ }
+ else
+ {
+ if (get_base4_color(0) != get_base4_color(1))
+ return false;
+ }
+
+ return true;
+ }
+
+ // Returned encoded selector value ranges from 0-3 (this is NOT a direct index into g_etc1_inten_tables, see get_selector())
+ inline uint32_t get_raw_selector(uint32_t x, uint32_t y) const
+ {
+ assert((x | y) < 4);
+
+ const uint32_t bit_index = x * 4 + y;
+ const uint32_t byte_bit_ofs = bit_index & 7;
+ const uint8_t *p = &m_bytes[7 - (bit_index >> 3)];
+ const uint32_t lsb = (p[0] >> byte_bit_ofs) & 1;
+ const uint32_t msb = (p[-2] >> byte_bit_ofs) & 1;
+ const uint32_t val = lsb | (msb << 1);
+
+ return val;
+ }
+
+ // Returned selector value ranges from 0-3 and is a direct index into g_etc1_inten_tables.
+ inline uint32_t get_selector(uint32_t x, uint32_t y) const
+ {
+ return g_etc1_to_selector_index[get_raw_selector(x, y)];
+ }
+
+ // Selector "val" ranges from 0-3 and is a direct index into g_etc1_inten_tables.
+ inline void set_selector(uint32_t x, uint32_t y, uint32_t val)
+ {
+ assert((x | y | val) < 4);
+ const uint32_t bit_index = x * 4 + y;
+
+ uint8_t *p = &m_bytes[7 - (bit_index >> 3)];
+
+ const uint32_t byte_bit_ofs = bit_index & 7;
+ const uint32_t mask = 1 << byte_bit_ofs;
+
+ const uint32_t etc1_val = g_selector_index_to_etc1[val];
+
+ const uint32_t lsb = etc1_val & 1;
+ const uint32_t msb = etc1_val >> 1;
+
+ p[0] &= ~mask;
+ p[0] |= (lsb << byte_bit_ofs);
+
+ p[-2] &= ~mask;
+ p[-2] |= (msb << byte_bit_ofs);
+ }
+
+ // Selector "etc1_val" ranges from 0-3 and is a direct (raw) ETC1 selector.
+ inline void set_raw_selector(uint32_t x, uint32_t y, uint32_t etc1_val)
+ {
+ assert((x | y | etc1_val) < 4);
+ const uint32_t bit_index = x * 4 + y;
+
+ uint8_t* p = &m_bytes[7 - (bit_index >> 3)];
+
+ const uint32_t byte_bit_ofs = bit_index & 7;
+ const uint32_t mask = 1 << byte_bit_ofs;
+
+ const uint32_t lsb = etc1_val & 1;
+ const uint32_t msb = etc1_val >> 1;
+
+ p[0] &= ~mask;
+ p[0] |= (lsb << byte_bit_ofs);
+
+ p[-2] &= ~mask;
+ p[-2] |= (msb << byte_bit_ofs);
+ }
+
+ inline uint32_t get_raw_selector_bits() const
+ {
+ return m_bytes[4] | (m_bytes[5] << 8) | (m_bytes[6] << 16) | (m_bytes[7] << 24);
+ }
+
+ inline void set_raw_selector_bits(uint32_t bits)
+ {
+ m_bytes[4] = static_cast<uint8_t>(bits);
+ m_bytes[5] = static_cast<uint8_t>(bits >> 8);
+ m_bytes[6] = static_cast<uint8_t>(bits >> 16);
+ m_bytes[7] = static_cast<uint8_t>(bits >> 24);
+ }
+
+ inline void set_raw_selector_bits(uint8_t byte0, uint8_t byte1, uint8_t byte2, uint8_t byte3)
+ {
+ m_bytes[4] = byte0;
+ m_bytes[5] = byte1;
+ m_bytes[6] = byte2;
+ m_bytes[7] = byte3;
+ }
+
+ inline void set_base4_color(uint32_t idx, uint16_t c)
+ {
+ if (idx)
+ {
+ set_byte_bits(cETC1AbsColor4R2BitOffset, 4, (c >> 8) & 15);
+ set_byte_bits(cETC1AbsColor4G2BitOffset, 4, (c >> 4) & 15);
+ set_byte_bits(cETC1AbsColor4B2BitOffset, 4, c & 15);
+ }
+ else
+ {
+ set_byte_bits(cETC1AbsColor4R1BitOffset, 4, (c >> 8) & 15);
+ set_byte_bits(cETC1AbsColor4G1BitOffset, 4, (c >> 4) & 15);
+ set_byte_bits(cETC1AbsColor4B1BitOffset, 4, c & 15);
+ }
+ }
+
+ inline uint16_t get_base4_color(uint32_t idx) const
+ {
+ uint32_t r, g, b;
+ if (idx)
+ {
+ r = get_byte_bits(cETC1AbsColor4R2BitOffset, 4);
+ g = get_byte_bits(cETC1AbsColor4G2BitOffset, 4);
+ b = get_byte_bits(cETC1AbsColor4B2BitOffset, 4);
+ }
+ else
+ {
+ r = get_byte_bits(cETC1AbsColor4R1BitOffset, 4);
+ g = get_byte_bits(cETC1AbsColor4G1BitOffset, 4);
+ b = get_byte_bits(cETC1AbsColor4B1BitOffset, 4);
+ }
+ return static_cast<uint16_t>(b | (g << 4U) | (r << 8U));
+ }
+
+ inline void set_base5_color(uint16_t c)
+ {
+ set_byte_bits(cETC1BaseColor5RBitOffset, 5, (c >> 10) & 31);
+ set_byte_bits(cETC1BaseColor5GBitOffset, 5, (c >> 5) & 31);
+ set_byte_bits(cETC1BaseColor5BBitOffset, 5, c & 31);
+ }
+
+ inline uint16_t get_base5_color() const
+ {
+ const uint32_t r = get_byte_bits(cETC1BaseColor5RBitOffset, 5);
+ const uint32_t g = get_byte_bits(cETC1BaseColor5GBitOffset, 5);
+ const uint32_t b = get_byte_bits(cETC1BaseColor5BBitOffset, 5);
+ return static_cast<uint16_t>(b | (g << 5U) | (r << 10U));
+ }
+
+ void set_delta3_color(uint16_t c)
+ {
+ set_byte_bits(cETC1DeltaColor3RBitOffset, 3, (c >> 6) & 7);
+ set_byte_bits(cETC1DeltaColor3GBitOffset, 3, (c >> 3) & 7);
+ set_byte_bits(cETC1DeltaColor3BBitOffset, 3, c & 7);
+ }
+
+ inline uint16_t get_delta3_color() const
+ {
+ const uint32_t r = get_byte_bits(cETC1DeltaColor3RBitOffset, 3);
+ const uint32_t g = get_byte_bits(cETC1DeltaColor3GBitOffset, 3);
+ const uint32_t b = get_byte_bits(cETC1DeltaColor3BBitOffset, 3);
+ return static_cast<uint16_t>(b | (g << 3U) | (r << 6U));
+ }
+
+ uint64_t determine_selectors(const color_rgba* pSource_pixels, bool perceptual, uint32_t begin_subblock = 0, uint32_t end_subblock = 2)
+ {
+ uint64_t total_error = 0;
+
+ for (uint32_t subblock = begin_subblock; subblock < end_subblock; subblock++)
+ {
+ color_rgba block_colors[4];
+ get_block_colors(block_colors, subblock);
+
+ if (get_flip_bit())
+ {
+ for (uint32_t y = 0; y < 2; y++)
+ {
+ for (uint32_t x = 0; x < 4; x++)
+ {
+ uint32_t best_selector = 0;
+ uint64_t best_error = UINT64_MAX;
+
+ for (uint32_t s = 0; s < 4; s++)
+ {
+ uint64_t err = color_distance(perceptual, block_colors[s], pSource_pixels[x + (subblock * 2 + y) * 4], false);
+ if (err < best_error)
+ {
+ best_error = err;
+ best_selector = s;
+ }
+ }
+
+ set_selector(x, subblock * 2 + y, best_selector);
+
+ total_error += best_error;
+ }
+ }
+ }
+ else
+ {
+ for (uint32_t y = 0; y < 4; y++)
+ {
+ for (uint32_t x = 0; x < 2; x++)
+ {
+ uint32_t best_selector = 0;
+ uint64_t best_error = UINT64_MAX;
+
+ for (uint32_t s = 0; s < 4; s++)
+ {
+ uint64_t err = color_distance(perceptual, block_colors[s], pSource_pixels[(subblock * 2) + x + y * 4], false);
+ if (err < best_error)
+ {
+ best_error = err;
+ best_selector = s;
+ }
+ }
+
+ set_selector(subblock * 2 + x, y, best_selector);
+
+ total_error += best_error;
+ }
+ }
+ }
+ }
+
+ return total_error;
+ }
+
+ color_rgba get_block_color(uint32_t subblock_index, bool scaled) const
+ {
+ color_rgba b;
+
+ if (get_diff_bit())
+ {
+ if (subblock_index)
+ unpack_color5(b, get_base5_color(), get_delta3_color(), scaled);
+ else
+ unpack_color5(b, get_base5_color(), scaled);
+ }
+ else
+ {
+ b = unpack_color4(get_base4_color(subblock_index), scaled);
+ }
+
+ return b;
+ }
+
+ uint32_t get_subblock_index(uint32_t x, uint32_t y) const
+ {
+ if (get_flip_bit())
+ return y >= 2;
+ else
+ return x >= 2;
+ }
+
+ bool get_block_colors(color_rgba* pBlock_colors, uint32_t subblock_index) const
+ {
+ color_rgba b;
+
+ if (get_diff_bit())
+ {
+ if (subblock_index)
+ unpack_color5(b, get_base5_color(), get_delta3_color(), true);
+ else
+ unpack_color5(b, get_base5_color(), true);
+ }
+ else
+ {
+ b = unpack_color4(get_base4_color(subblock_index), true);
+ }
+
+ const int* pInten_table = g_etc1_inten_tables[get_inten_table(subblock_index)];
+
+ bool dc = false;
+
+ pBlock_colors[0].set(clamp255(b.r + pInten_table[0], dc), clamp255(b.g + pInten_table[0], dc), clamp255(b.b + pInten_table[0], dc), 255);
+ pBlock_colors[1].set(clamp255(b.r + pInten_table[1], dc), clamp255(b.g + pInten_table[1], dc), clamp255(b.b + pInten_table[1], dc), 255);
+ pBlock_colors[2].set(clamp255(b.r + pInten_table[2], dc), clamp255(b.g + pInten_table[2], dc), clamp255(b.b + pInten_table[2], dc), 255);
+ pBlock_colors[3].set(clamp255(b.r + pInten_table[3], dc), clamp255(b.g + pInten_table[3], dc), clamp255(b.b + pInten_table[3], dc), 255);
+
+ return dc;
+ }
+
+ void get_block_color(color_rgba& color, uint32_t subblock_index, uint32_t selector_index) const
+ {
+ color_rgba b;
+
+ if (get_diff_bit())
+ {
+ if (subblock_index)
+ unpack_color5(b, get_base5_color(), get_delta3_color(), true);
+ else
+ unpack_color5(b, get_base5_color(), true);
+ }
+ else
+ {
+ b = unpack_color4(get_base4_color(subblock_index), true);
+ }
+
+ const int* pInten_table = g_etc1_inten_tables[get_inten_table(subblock_index)];
+
+ color.set(clamp255(b.r + pInten_table[selector_index]), clamp255(b.g + pInten_table[selector_index]), clamp255(b.b + pInten_table[selector_index]), 255);
+ }
+
+ bool get_block_low_high_colors(color_rgba* pBlock_colors, uint32_t subblock_index) const
+ {
+ color_rgba b;
+
+ if (get_diff_bit())
+ {
+ if (subblock_index)
+ unpack_color5(b, get_base5_color(), get_delta3_color(), true);
+ else
+ unpack_color5(b, get_base5_color(), true);
+ }
+ else
+ {
+ b = unpack_color4(get_base4_color(subblock_index), true);
+ }
+
+ const int* pInten_table = g_etc1_inten_tables[get_inten_table(subblock_index)];
+
+ bool dc = false;
+
+ pBlock_colors[0].set(clamp255(b.r + pInten_table[0], dc), clamp255(b.g + pInten_table[0], dc), clamp255(b.b + pInten_table[0], dc), 255);
+ pBlock_colors[1].set(clamp255(b.r + pInten_table[3], dc), clamp255(b.g + pInten_table[3], dc), clamp255(b.b + pInten_table[3], dc), 255);
+
+ return dc;
+ }
+
+ static void get_block_colors5(color_rgba *pBlock_colors, const color_rgba &base_color5, uint32_t inten_table, bool scaled = false)
+ {
+ color_rgba b(base_color5);
+
+ if (!scaled)
+ {
+ b.r = (b.r << 3) | (b.r >> 2);
+ b.g = (b.g << 3) | (b.g >> 2);
+ b.b = (b.b << 3) | (b.b >> 2);
+ }
+
+ const int* pInten_table = g_etc1_inten_tables[inten_table];
+
+ pBlock_colors[0].set(clamp255(b.r + pInten_table[0]), clamp255(b.g + pInten_table[0]), clamp255(b.b + pInten_table[0]), 255);
+ pBlock_colors[1].set(clamp255(b.r + pInten_table[1]), clamp255(b.g + pInten_table[1]), clamp255(b.b + pInten_table[1]), 255);
+ pBlock_colors[2].set(clamp255(b.r + pInten_table[2]), clamp255(b.g + pInten_table[2]), clamp255(b.b + pInten_table[2]), 255);
+ pBlock_colors[3].set(clamp255(b.r + pInten_table[3]), clamp255(b.g + pInten_table[3]), clamp255(b.b + pInten_table[3]), 255);
+ }
+
+ static void get_block_colors4(color_rgba *pBlock_colors, const color_rgba &base_color4, uint32_t inten_table, bool scaled = false)
+ {
+ color_rgba b(base_color4);
+
+ if (!scaled)
+ {
+ b.r = (b.r << 4) | b.r;
+ b.g = (b.g << 4) | b.g;
+ b.b = (b.b << 4) | b.b;
+ }
+
+ const int* pInten_table = g_etc1_inten_tables[inten_table];
+
+ pBlock_colors[0].set(clamp255(b.r + pInten_table[0]), clamp255(b.g + pInten_table[0]), clamp255(b.b + pInten_table[0]), 255);
+ pBlock_colors[1].set(clamp255(b.r + pInten_table[1]), clamp255(b.g + pInten_table[1]), clamp255(b.b + pInten_table[1]), 255);
+ pBlock_colors[2].set(clamp255(b.r + pInten_table[2]), clamp255(b.g + pInten_table[2]), clamp255(b.b + pInten_table[2]), 255);
+ pBlock_colors[3].set(clamp255(b.r + pInten_table[3]), clamp255(b.g + pInten_table[3]), clamp255(b.b + pInten_table[3]), 255);
+ }
+
+ uint64_t evaluate_etc1_error(const color_rgba* pBlock_pixels, bool perceptual, int subblock_index = -1) const;
+ void get_subblock_pixels(color_rgba* pPixels, int subblock_index = -1) const;
+
+ void get_selector_range(uint32_t& low, uint32_t& high) const
+ {
+ low = 3;
+ high = 0;
+ for (uint32_t y = 0; y < 4; y++)
+ {
+ for (uint32_t x = 0; x < 4; x++)
+ {
+ const uint32_t s = get_selector(x, y);
+ low = minimum(low, s);
+ high = maximum(high, s);
+ }
+ }
+ }
+
+ void set_block_color4(const color_rgba &c0_unscaled, const color_rgba &c1_unscaled)
+ {
+ set_diff_bit(false);
+
+ set_base4_color(0, pack_color4(c0_unscaled, false));
+ set_base4_color(1, pack_color4(c1_unscaled, false));
+ }
+
+ void set_block_color5(const color_rgba &c0_unscaled, const color_rgba &c1_unscaled)
+ {
+ set_diff_bit(true);
+
+ set_base5_color(pack_color5(c0_unscaled, false));
+
+ int dr = c1_unscaled.r - c0_unscaled.r;
+ int dg = c1_unscaled.g - c0_unscaled.g;
+ int db = c1_unscaled.b - c0_unscaled.b;
+
+ set_delta3_color(pack_delta3(dr, dg, db));
+ }
+
+ void set_block_color5_etc1s(const color_rgba &c_unscaled)
+ {
+ set_diff_bit(true);
+
+ set_base5_color(pack_color5(c_unscaled, false));
+ set_delta3_color(pack_delta3(0, 0, 0));
+ }
+
+ bool set_block_color5_check(const color_rgba &c0_unscaled, const color_rgba &c1_unscaled)
+ {
+ set_diff_bit(true);
+
+ set_base5_color(pack_color5(c0_unscaled, false));
+
+ int dr = c1_unscaled.r - c0_unscaled.r;
+ int dg = c1_unscaled.g - c0_unscaled.g;
+ int db = c1_unscaled.b - c0_unscaled.b;
+
+ if (((dr < cETC1ColorDeltaMin) || (dr > cETC1ColorDeltaMax)) ||
+ ((dg < cETC1ColorDeltaMin) || (dg > cETC1ColorDeltaMax)) ||
+ ((db < cETC1ColorDeltaMin) || (db > cETC1ColorDeltaMax)))
+ return false;
+
+ set_delta3_color(pack_delta3(dr, dg, db));
+
+ return true;
+ }
+
+ bool set_block_color5_clamp(const color_rgba &c0_unscaled, const color_rgba &c1_unscaled)
+ {
+ set_diff_bit(true);
+ set_base5_color(pack_color5(c0_unscaled, false));
+
+ int dr = c1_unscaled.r - c0_unscaled.r;
+ int dg = c1_unscaled.g - c0_unscaled.g;
+ int db = c1_unscaled.b - c0_unscaled.b;
+
+ dr = clamp<int>(dr, cETC1ColorDeltaMin, cETC1ColorDeltaMax);
+ dg = clamp<int>(dg, cETC1ColorDeltaMin, cETC1ColorDeltaMax);
+ db = clamp<int>(db, cETC1ColorDeltaMin, cETC1ColorDeltaMax);
+
+ set_delta3_color(pack_delta3(dr, dg, db));
+
+ return true;
+ }
+ color_rgba get_selector_color(uint32_t x, uint32_t y, uint32_t s) const
+ {
+ color_rgba block_colors[4];
+
+ get_block_colors(block_colors, get_subblock_index(x, y));
+
+ return block_colors[s];
+ }
+
+ // Base color 5
+ static uint16_t pack_color5(const color_rgba& color, bool scaled, uint32_t bias = 127U);
+ static uint16_t pack_color5(uint32_t r, uint32_t g, uint32_t b, bool scaled, uint32_t bias = 127U);
+
+ static color_rgba unpack_color5(uint16_t packed_color5, bool scaled, uint32_t alpha = 255U);
+ static void unpack_color5(uint32_t& r, uint32_t& g, uint32_t& b, uint16_t packed_color, bool scaled);
+ static void unpack_color5(color_rgba& result, uint16_t packed_color5, bool scaled);
+
+ static bool unpack_color5(color_rgba& result, uint16_t packed_color5, uint16_t packed_delta3, bool scaled, uint32_t alpha = 255U);
+ static bool unpack_color5(uint32_t& r, uint32_t& g, uint32_t& b, uint16_t packed_color5, uint16_t packed_delta3, bool scaled, uint32_t alpha = 255U);
+
+ // Delta color 3
+ // Inputs range from -4 to 3 (cETC1ColorDeltaMin to cETC1ColorDeltaMax)
+ static uint16_t pack_delta3(const color_rgba_i16& color);
+ static uint16_t pack_delta3(int r, int g, int b);
+
+ // Results range from -4 to 3 (cETC1ColorDeltaMin to cETC1ColorDeltaMax)
+ static color_rgba_i16 unpack_delta3(uint16_t packed_delta3);
+ static void unpack_delta3(int& r, int& g, int& b, uint16_t packed_delta3);
+
+ static bool try_pack_color5_delta3(const color_rgba *pColor5_unscaled)
+ {
+ int dr = pColor5_unscaled[1].r - pColor5_unscaled[0].r;
+ int dg = pColor5_unscaled[1].g - pColor5_unscaled[0].g;
+ int db = pColor5_unscaled[1].b - pColor5_unscaled[0].b;
+
+ if ((minimum(dr, dg, db) < cETC1ColorDeltaMin) || (maximum(dr, dg, db) > cETC1ColorDeltaMax))
+ return false;
+
+ return true;
+ }
+
+ // Abs color 4
+ static uint16_t pack_color4(const color_rgba& color, bool scaled, uint32_t bias = 127U);
+ static uint16_t pack_color4(uint32_t r, uint32_t g, uint32_t b, bool scaled, uint32_t bias = 127U);
+
+ static color_rgba unpack_color4(uint16_t packed_color4, bool scaled, uint32_t alpha = 255U);
+ static void unpack_color4(uint32_t& r, uint32_t& g, uint32_t& b, uint16_t packed_color4, bool scaled);
+
+ // subblock colors
+ static void get_diff_subblock_colors(color_rgba* pDst, uint16_t packed_color5, uint32_t table_idx);
+ static bool get_diff_subblock_colors(color_rgba* pDst, uint16_t packed_color5, uint16_t packed_delta3, uint32_t table_idx);
+ static void get_abs_subblock_colors(color_rgba* pDst, uint16_t packed_color4, uint32_t table_idx);
+
+ static inline void unscaled_to_scaled_color(color_rgba& dst, const color_rgba& src, bool color4)
+ {
+ if (color4)
+ {
+ dst.r = src.r | (src.r << 4);
+ dst.g = src.g | (src.g << 4);
+ dst.b = src.b | (src.b << 4);
+ }
+ else
+ {
+ dst.r = (src.r >> 2) | (src.r << 3);
+ dst.g = (src.g >> 2) | (src.g << 3);
+ dst.b = (src.b >> 2) | (src.b << 3);
+ }
+ dst.a = src.a;
+ }
+
+ private:
+ static uint8_t clamp255(int x, bool &did_clamp)
+ {
+ if (x < 0)
+ {
+ did_clamp = true;
+ return 0;
+ }
+ else if (x > 255)
+ {
+ did_clamp = true;
+ return 255;
+ }
+
+ return static_cast<uint8_t>(x);
+ }
+
+ static uint8_t clamp255(int x)
+ {
+ if (x < 0)
+ return 0;
+ else if (x > 255)
+ return 255;
+
+ return static_cast<uint8_t>(x);
+ }
+ };
+
+ typedef basisu::vector<etc_block> etc_block_vec;
+
+ // Returns false if the unpack fails (could be bogus data or ETC2)
+ bool unpack_etc1(const etc_block& block, color_rgba *pDst, bool preserve_alpha = false);
+
+ enum basis_etc_quality
+ {
+ cETCQualityFast,
+ cETCQualityMedium,
+ cETCQualitySlow,
+ cETCQualityUber,
+ cETCQualityTotal,
+ };
+
+ struct basis_etc1_pack_params
+ {
+ basis_etc_quality m_quality;
+ bool m_perceptual;
+ bool m_cluster_fit;
+ bool m_force_etc1s;
+ bool m_use_color4;
+ float m_flip_bias;
+
+ inline basis_etc1_pack_params()
+ {
+ clear();
+ }
+
+ void clear()
+ {
+ m_quality = cETCQualitySlow;
+ m_perceptual = true;
+ m_cluster_fit = true;
+ m_force_etc1s = false;
+ m_use_color4 = true;
+ m_flip_bias = 0.0f;
+ }
+ };
+
+ struct etc1_solution_coordinates
+ {
+ inline etc1_solution_coordinates() :
+ m_unscaled_color(0, 0, 0, 0),
+ m_inten_table(0),
+ m_color4(false)
+ {
+ }
+
+ inline etc1_solution_coordinates(uint32_t r, uint32_t g, uint32_t b, uint32_t inten_table, bool color4) :
+ m_unscaled_color((uint8_t)r, (uint8_t)g, (uint8_t)b, 255),
+ m_inten_table((uint8_t)inten_table),
+ m_color4(color4)
+ {
+ }
+
+ inline etc1_solution_coordinates(const color_rgba& c, uint32_t inten_table, bool color4) :
+ m_unscaled_color(c),
+ m_inten_table(inten_table),
+ m_color4(color4)
+ {
+ }
+
+ inline etc1_solution_coordinates(const etc1_solution_coordinates& other)
+ {
+ *this = other;
+ }
+
+ inline etc1_solution_coordinates& operator= (const etc1_solution_coordinates& rhs)
+ {
+ m_unscaled_color = rhs.m_unscaled_color;
+ m_inten_table = rhs.m_inten_table;
+ m_color4 = rhs.m_color4;
+ return *this;
+ }
+
+ inline void clear()
+ {
+ m_unscaled_color.clear();
+ m_inten_table = 0;
+ m_color4 = false;
+ }
+
+ inline void init(const color_rgba& c, uint32_t inten_table, bool color4)
+ {
+ m_unscaled_color = c;
+ m_inten_table = inten_table;
+ m_color4 = color4;
+ }
+
+ inline color_rgba get_scaled_color() const
+ {
+ int br, bg, bb;
+ if (m_color4)
+ {
+ br = m_unscaled_color.r | (m_unscaled_color.r << 4);
+ bg = m_unscaled_color.g | (m_unscaled_color.g << 4);
+ bb = m_unscaled_color.b | (m_unscaled_color.b << 4);
+ }
+ else
+ {
+ br = (m_unscaled_color.r >> 2) | (m_unscaled_color.r << 3);
+ bg = (m_unscaled_color.g >> 2) | (m_unscaled_color.g << 3);
+ bb = (m_unscaled_color.b >> 2) | (m_unscaled_color.b << 3);
+ }
+ return color_rgba((uint8_t)br, (uint8_t)bg, (uint8_t)bb, 255);
+ }
+
+ // returns true if anything was clamped
+ inline void get_block_colors(color_rgba* pBlock_colors)
+ {
+ int br, bg, bb;
+ if (m_color4)
+ {
+ br = m_unscaled_color.r | (m_unscaled_color.r << 4);
+ bg = m_unscaled_color.g | (m_unscaled_color.g << 4);
+ bb = m_unscaled_color.b | (m_unscaled_color.b << 4);
+ }
+ else
+ {
+ br = (m_unscaled_color.r >> 2) | (m_unscaled_color.r << 3);
+ bg = (m_unscaled_color.g >> 2) | (m_unscaled_color.g << 3);
+ bb = (m_unscaled_color.b >> 2) | (m_unscaled_color.b << 3);
+ }
+ const int* pInten_table = g_etc1_inten_tables[m_inten_table];
+ pBlock_colors[0].set(br + pInten_table[0], bg + pInten_table[0], bb + pInten_table[0], 255);
+ pBlock_colors[1].set(br + pInten_table[1], bg + pInten_table[1], bb + pInten_table[1], 255);
+ pBlock_colors[2].set(br + pInten_table[2], bg + pInten_table[2], bb + pInten_table[2], 255);
+ pBlock_colors[3].set(br + pInten_table[3], bg + pInten_table[3], bb + pInten_table[3], 255);
+ }
+
+ color_rgba m_unscaled_color;
+ uint32_t m_inten_table;
+ bool m_color4;
+ };
+
+ class etc1_optimizer
+ {
+ BASISU_NO_EQUALS_OR_COPY_CONSTRUCT(etc1_optimizer);
+
+ public:
+ etc1_optimizer()
+ {
+ clear();
+ }
+
+ void clear()
+ {
+ m_pParams = nullptr;
+ m_pResult = nullptr;
+ m_pSorted_luma = nullptr;
+ m_pSorted_luma_indices = nullptr;
+ }
+
+ struct params;
+
+ typedef bool(*evaluate_solution_override_func)(uint64_t &error, const params &p, const color_rgba* pBlock_colors, const uint8_t* pSelectors, const etc1_solution_coordinates& coords);
+
+ struct params : basis_etc1_pack_params
+ {
+ params()
+ {
+ clear();
+ }
+
+ params(const basis_etc1_pack_params& base_params)
+ {
+ clear_optimizer_params();
+
+ *static_cast<basis_etc1_pack_params *>(this) = base_params;
+ }
+
+ void clear()
+ {
+ clear_optimizer_params();
+ }
+
+ void clear_optimizer_params()
+ {
+ basis_etc1_pack_params::clear();
+
+ m_num_src_pixels = 0;
+ m_pSrc_pixels = 0;
+
+ m_use_color4 = false;
+ static const int s_default_scan_delta[] = { 0 };
+ m_pScan_deltas = s_default_scan_delta;
+ m_scan_delta_size = 1;
+
+ m_base_color5.clear();
+ m_constrain_against_base_color5 = false;
+
+ m_refinement = true;
+
+ m_pForce_selectors = nullptr;
+ }
+
+ uint32_t m_num_src_pixels;
+ const color_rgba* m_pSrc_pixels;
+
+ bool m_use_color4;
+ const int* m_pScan_deltas;
+ uint32_t m_scan_delta_size;
+
+ color_rgba m_base_color5;
+ bool m_constrain_against_base_color5;
+
+ bool m_refinement;
+
+ const uint8_t* m_pForce_selectors;
+ };
+
+ struct results
+ {
+ uint64_t m_error;
+ color_rgba m_block_color_unscaled;
+ uint32_t m_block_inten_table;
+ uint32_t m_n;
+ uint8_t* m_pSelectors;
+ bool m_block_color4;
+
+ inline results& operator= (const results& rhs)
+ {
+ m_block_color_unscaled = rhs.m_block_color_unscaled;
+ m_block_color4 = rhs.m_block_color4;
+ m_block_inten_table = rhs.m_block_inten_table;
+ m_error = rhs.m_error;
+ memcpy(m_pSelectors, rhs.m_pSelectors, minimum(rhs.m_n, m_n));
+ return *this;
+ }
+ };
+
+ void init(const params& params, results& result);
+ bool compute();
+
+ const params* get_params() const { return m_pParams; }
+
+ private:
+ struct potential_solution
+ {
+ potential_solution() : m_coords(), m_error(UINT64_MAX), m_valid(false)
+ {
+ }
+
+ etc1_solution_coordinates m_coords;
+ basisu::vector<uint8_t> m_selectors;
+ uint64_t m_error;
+ bool m_valid;
+
+ void clear()
+ {
+ m_coords.clear();
+ m_selectors.resize(0);
+ m_error = UINT64_MAX;
+ m_valid = false;
+ }
+
+ bool are_selectors_all_equal() const
+ {
+ if (!m_selectors.size())
+ return false;
+ const uint32_t s = m_selectors[0];
+ for (uint32_t i = 1; i < m_selectors.size(); i++)
+ if (m_selectors[i] != s)
+ return false;
+ return true;
+ }
+ };
+
+ const params* m_pParams;
+ results* m_pResult;
+
+ int m_limit;
+
+ vec3F m_avg_color;
+ int m_br, m_bg, m_bb;
+ int m_max_comp_spread;
+ basisu::vector<uint16_t> m_luma;
+ basisu::vector<uint32_t> m_sorted_luma;
+ basisu::vector<uint32_t> m_sorted_luma_indices;
+ const uint32_t* m_pSorted_luma_indices;
+ uint32_t* m_pSorted_luma;
+
+ basisu::vector<uint8_t> m_selectors;
+ basisu::vector<uint8_t> m_best_selectors;
+
+ potential_solution m_best_solution;
+ potential_solution m_trial_solution;
+ basisu::vector<uint8_t> m_temp_selectors;
+
+ enum { cSolutionsTriedHashBits = 10, cTotalSolutionsTriedHashSize = 1 << cSolutionsTriedHashBits, cSolutionsTriedHashMask = cTotalSolutionsTriedHashSize - 1 };
+ uint8_t m_solutions_tried[cTotalSolutionsTriedHashSize / 8];
+
+ void get_nearby_inten_tables(uint32_t idx, int &first_inten_table, int &last_inten_table)
+ {
+ first_inten_table = maximum<int>(idx - 1, 0);
+ last_inten_table = minimum<int>(cETC1IntenModifierValues, idx + 1);
+ }
+
+ bool check_for_redundant_solution(const etc1_solution_coordinates& coords);
+ bool evaluate_solution_slow(const etc1_solution_coordinates& coords, potential_solution& trial_solution, potential_solution* pBest_solution);
+ bool evaluate_solution_fast(const etc1_solution_coordinates& coords, potential_solution& trial_solution, potential_solution* pBest_solution);
+
+ inline bool evaluate_solution(const etc1_solution_coordinates& coords, potential_solution& trial_solution, potential_solution* pBest_solution)
+ {
+ if (m_pParams->m_quality >= cETCQualityMedium)
+ return evaluate_solution_slow(coords, trial_solution, pBest_solution);
+ else
+ return evaluate_solution_fast(coords, trial_solution, pBest_solution);
+ }
+
+ void refine_solution(uint32_t max_refinement_trials);
+ void compute_internal_neighborhood(int scan_r, int scan_g, int scan_b);
+ void compute_internal_cluster_fit(uint32_t total_perms_to_try);
+ };
+
+ struct pack_etc1_block_context
+ {
+ etc1_optimizer m_optimizer;
+ };
+
+ void pack_etc1_solid_color_init();
+ uint64_t pack_etc1_block_solid_color(etc_block& block, const uint8_t* pColor);
+
+ // ETC EAC
+ extern const int8_t g_etc2_eac_tables[16][8];
+ extern const int8_t g_etc2_eac_tables8[16][8];
+
+ const uint32_t ETC2_EAC_MIN_VALUE_SELECTOR = 3, ETC2_EAC_MAX_VALUE_SELECTOR = 7;
+
+ struct eac_a8_block
+ {
+ uint16_t m_base : 8;
+ uint16_t m_table : 4;
+ uint16_t m_multiplier : 4;
+
+ uint8_t m_selectors[6];
+
+ inline uint32_t get_selector(uint32_t x, uint32_t y, uint64_t selector_bits) const
+ {
+ assert((x < 4) && (y < 4));
+ return static_cast<uint32_t>((selector_bits >> (45 - (y + x * 4) * 3)) & 7);
+ }
+
+ inline uint64_t get_selector_bits() const
+ {
+ uint64_t pixels = ((uint64_t)m_selectors[0] << 40) | ((uint64_t)m_selectors[1] << 32) | ((uint64_t)m_selectors[2] << 24) | ((uint64_t)m_selectors[3] << 16) | ((uint64_t)m_selectors[4] << 8) | m_selectors[5];
+ return pixels;
+ }
+
+ inline void set_selector_bits(uint64_t pixels)
+ {
+ m_selectors[0] = (uint8_t)(pixels >> 40);
+ m_selectors[1] = (uint8_t)(pixels >> 32);
+ m_selectors[2] = (uint8_t)(pixels >> 24);
+ m_selectors[3] = (uint8_t)(pixels >> 16);
+ m_selectors[4] = (uint8_t)(pixels >> 8);
+ m_selectors[5] = (uint8_t)(pixels);
+ }
+
+ void set_selector(uint32_t x, uint32_t y, uint32_t s)
+ {
+ assert((x < 4) && (y < 4) && (s < 8));
+
+ const uint32_t ofs = 45 - (y + x * 4) * 3;
+
+ uint64_t pixels = get_selector_bits();
+
+ pixels &= ~(7ULL << ofs);
+ pixels |= (static_cast<uint64_t>(s) << ofs);
+
+ set_selector_bits(pixels);
+ }
+ };
+
+ struct etc2_rgba_block
+ {
+ eac_a8_block m_alpha;
+ etc_block m_rgb;
+ };
+
+ struct pack_eac_a8_results
+ {
+ uint32_t m_base;
+ uint32_t m_table;
+ uint32_t m_multiplier;
+ uint8_vec m_selectors;
+ uint8_vec m_selectors_temp;
+ };
+
+ 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 = UINT32_MAX);
+ 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 = UINT32_MAX);
+
+} // namespace basisu