mirror of
https://git.suyu.dev/suyu/suyu.git
synced 2024-11-25 22:57:22 +00:00
122 lines
3.6 KiB
C++
122 lines
3.6 KiB
C++
// Copyright 2017 Citra Emulator Project
|
|
// Licensed under GPLv2 or any later version
|
|
// Refer to the license.txt file included.
|
|
|
|
#include <array>
|
|
#include "common/bit_field.h"
|
|
#include "common/color.h"
|
|
#include "common/common_types.h"
|
|
#include "common/math_util.h"
|
|
#include "common/vector_math.h"
|
|
#include "video_core/texture/etc1.h"
|
|
|
|
namespace Pica {
|
|
namespace Texture {
|
|
|
|
namespace {
|
|
|
|
constexpr std::array<std::array<u8, 2>, 8> etc1_modifier_table = {{
|
|
{2, 8}, {5, 17}, {9, 29}, {13, 42}, {18, 60}, {24, 80}, {33, 106}, {47, 183},
|
|
}};
|
|
|
|
union ETC1Tile {
|
|
u64 raw;
|
|
|
|
// Each of these two is a collection of 16 bits (one per lookup value)
|
|
BitField<0, 16, u64> table_subindexes;
|
|
BitField<16, 16, u64> negation_flags;
|
|
|
|
unsigned GetTableSubIndex(unsigned index) const {
|
|
return (table_subindexes >> index) & 1;
|
|
}
|
|
|
|
bool GetNegationFlag(unsigned index) const {
|
|
return ((negation_flags >> index) & 1) == 1;
|
|
}
|
|
|
|
BitField<32, 1, u64> flip;
|
|
BitField<33, 1, u64> differential_mode;
|
|
|
|
BitField<34, 3, u64> table_index_2;
|
|
BitField<37, 3, u64> table_index_1;
|
|
|
|
union {
|
|
// delta value + base value
|
|
BitField<40, 3, s64> db;
|
|
BitField<43, 5, u64> b;
|
|
|
|
BitField<48, 3, s64> dg;
|
|
BitField<51, 5, u64> g;
|
|
|
|
BitField<56, 3, s64> dr;
|
|
BitField<59, 5, u64> r;
|
|
} differential;
|
|
|
|
union {
|
|
BitField<40, 4, u64> b2;
|
|
BitField<44, 4, u64> b1;
|
|
|
|
BitField<48, 4, u64> g2;
|
|
BitField<52, 4, u64> g1;
|
|
|
|
BitField<56, 4, u64> r2;
|
|
BitField<60, 4, u64> r1;
|
|
} separate;
|
|
|
|
const Math::Vec3<u8> GetRGB(unsigned int x, unsigned int y) const {
|
|
int texel = 4 * x + y;
|
|
|
|
if (flip)
|
|
std::swap(x, y);
|
|
|
|
// Lookup base value
|
|
Math::Vec3<int> ret;
|
|
if (differential_mode) {
|
|
ret.r() = static_cast<int>(differential.r);
|
|
ret.g() = static_cast<int>(differential.g);
|
|
ret.b() = static_cast<int>(differential.b);
|
|
if (x >= 2) {
|
|
ret.r() += static_cast<int>(differential.dr);
|
|
ret.g() += static_cast<int>(differential.dg);
|
|
ret.b() += static_cast<int>(differential.db);
|
|
}
|
|
ret.r() = Color::Convert5To8(ret.r());
|
|
ret.g() = Color::Convert5To8(ret.g());
|
|
ret.b() = Color::Convert5To8(ret.b());
|
|
} else {
|
|
if (x < 2) {
|
|
ret.r() = Color::Convert4To8(static_cast<u8>(separate.r1));
|
|
ret.g() = Color::Convert4To8(static_cast<u8>(separate.g1));
|
|
ret.b() = Color::Convert4To8(static_cast<u8>(separate.b1));
|
|
} else {
|
|
ret.r() = Color::Convert4To8(static_cast<u8>(separate.r2));
|
|
ret.g() = Color::Convert4To8(static_cast<u8>(separate.g2));
|
|
ret.b() = Color::Convert4To8(static_cast<u8>(separate.b2));
|
|
}
|
|
}
|
|
|
|
// Add modifier
|
|
unsigned table_index =
|
|
static_cast<int>((x < 2) ? table_index_1.Value() : table_index_2.Value());
|
|
|
|
int modifier = etc1_modifier_table[table_index][GetTableSubIndex(texel)];
|
|
if (GetNegationFlag(texel))
|
|
modifier *= -1;
|
|
|
|
ret.r() = MathUtil::Clamp(ret.r() + modifier, 0, 255);
|
|
ret.g() = MathUtil::Clamp(ret.g() + modifier, 0, 255);
|
|
ret.b() = MathUtil::Clamp(ret.b() + modifier, 0, 255);
|
|
|
|
return ret.Cast<u8>();
|
|
}
|
|
};
|
|
|
|
} // anonymous namespace
|
|
|
|
Math::Vec3<u8> SampleETC1Subtile(u64 value, unsigned int x, unsigned int y) {
|
|
ETC1Tile tile{value};
|
|
return tile.GetRGB(x, y);
|
|
}
|
|
|
|
} // namespace Texture
|
|
} // namespace Pica
|