// Copyright 2017 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include "common/assert.h"
#include "common/common_types.h"
#include "common/math_util.h"
#include "common/vector_math.h"
#include "video_core/regs_texturing.h"
#include "video_core/swrasterizer/texturing.h"
namespace Pica {
namespace Rasterizer {
using TevStageConfig = TexturingRegs::TevStageConfig;
int GetWrappedTexCoord(TexturingRegs::TextureConfig::WrapMode mode, int val, unsigned size) {
switch (mode) {
case TexturingRegs::TextureConfig::ClampToEdge2:
// For negative coordinate, ClampToEdge2 behaves the same as Repeat
if (val < 0) {
return static_cast<int>(static_cast<unsigned>(val) % size);
}
// [[fallthrough]]
case TexturingRegs::TextureConfig::ClampToEdge:
val = std::max(val, 0);
val = std::min(val, static_cast<int>(size) - 1);
return val;
case TexturingRegs::TextureConfig::ClampToBorder:
return val;
case TexturingRegs::TextureConfig::ClampToBorder2:
// For ClampToBorder2, the case of positive coordinate beyond the texture size is already
// handled outside. Here we only handle the negative coordinate in the same way as Repeat.
case TexturingRegs::TextureConfig::Repeat2:
case TexturingRegs::TextureConfig::Repeat3:
case TexturingRegs::TextureConfig::Repeat:
return static_cast<int>(static_cast<unsigned>(val) % size);
case TexturingRegs::TextureConfig::MirroredRepeat: {
unsigned int coord = (static_cast<unsigned>(val) % (2 * size));
if (coord >= size)
coord = 2 * size - 1 - coord;
return static_cast<int>(coord);
}
default:
LOG_ERROR(HW_GPU, "Unknown texture coordinate wrapping mode %x", (int)mode);
UNIMPLEMENTED();
return 0;
}
};
Math::Vec3<u8> GetColorModifier(TevStageConfig::ColorModifier factor,
const Math::Vec4<u8>& values) {
using ColorModifier = TevStageConfig::ColorModifier;
switch (factor) {
case ColorModifier::SourceColor:
return values.rgb();
case ColorModifier::OneMinusSourceColor:
return (Math::Vec3<u8>(255, 255, 255) - values.rgb()).Cast<u8>();
case ColorModifier::SourceAlpha:
return values.aaa();
case ColorModifier::OneMinusSourceAlpha:
return (Math::Vec3<u8>(255, 255, 255) - values.aaa()).Cast<u8>();
case ColorModifier::SourceRed:
return values.rrr();
case ColorModifier::OneMinusSourceRed:
return (Math::Vec3<u8>(255, 255, 255) - values.rrr()).Cast<u8>();
case ColorModifier::SourceGreen:
return values.ggg();
case ColorModifier::OneMinusSourceGreen:
return (Math::Vec3<u8>(255, 255, 255) - values.ggg()).Cast<u8>();
case ColorModifier::SourceBlue:
return values.bbb();
case ColorModifier::OneMinusSourceBlue:
return (Math::Vec3<u8>(255, 255, 255) - values.bbb()).Cast<u8>();
}
};
u8 GetAlphaModifier(TevStageConfig::AlphaModifier factor, const Math::Vec4<u8>& values) {
using AlphaModifier = TevStageConfig::AlphaModifier;
switch (factor) {
case AlphaModifier::SourceAlpha:
return values.a();
case AlphaModifier::OneMinusSourceAlpha:
return 255 - values.a();
case AlphaModifier::SourceRed:
return values.r();
case AlphaModifier::OneMinusSourceRed:
return 255 - values.r();
case AlphaModifier::SourceGreen:
return values.g();
case AlphaModifier::OneMinusSourceGreen:
return 255 - values.g();
case AlphaModifier::SourceBlue:
return values.b();
case AlphaModifier::OneMinusSourceBlue:
return 255 - values.b();
}
};
Math::Vec3<u8> ColorCombine(TevStageConfig::Operation op, const Math::Vec3<u8> input[3]) {
using Operation = TevStageConfig::Operation;
switch (op) {
case Operation::Replace:
return input[0];
case Operation::Modulate:
return ((input[0] * input[1]) / 255).Cast<u8>();
case Operation::Add: {
auto result = input[0] + input[1];
result.r() = std::min(255, result.r());
result.g() = std::min(255, result.g());
result.b() = std::min(255, result.b());
return result.Cast<u8>();
}
case Operation::AddSigned: {
// TODO(bunnei): Verify that the color conversion from (float) 0.5f to
// (byte) 128 is correct
auto result =
input[0].Cast<int>() + input[1].Cast<int>() - Math::MakeVec<int>(128, 128, 128);
result.r() = MathUtil::Clamp<int>(result.r(), 0, 255);
result.g() = MathUtil::Clamp<int>(result.g(), 0, 255);
result.b() = MathUtil::Clamp<int>(result.b(), 0, 255);
return result.Cast<u8>();
}
case Operation::Lerp:
return ((input[0] * input[2] +
input[1] * (Math::MakeVec<u8>(255, 255, 255) - input[2]).Cast<u8>()) /
255)
.Cast<u8>();
case Operation::Subtract: {
auto result = input[0].Cast<int>() - input[1].Cast<int>();
result.r() = std::max(0, result.r());
result.g() = std::max(0, result.g());
result.b() = std::max(0, result.b());
return result.Cast<u8>();
}
case Operation::MultiplyThenAdd: {
auto result = (input[0] * input[1] + 255 * input[2].Cast<int>()) / 255;
result.r() = std::min(255, result.r());
result.g() = std::min(255, result.g());
result.b() = std::min(255, result.b());
return result.Cast<u8>();
}
case Operation::AddThenMultiply: {
auto result = input[0] + input[1];
result.r() = std::min(255, result.r());
result.g() = std::min(255, result.g());
result.b() = std::min(255, result.b());
result = (result * input[2].Cast<int>()) / 255;
return result.Cast<u8>();
}
case Operation::Dot3_RGB:
case Operation::Dot3_RGBA: {
// Not fully accurate. Worst case scenario seems to yield a +/-3 error. Some HW results
// indicate that the per-component computation can't have a higher precision than 1/256,
// while dot3_rgb((0x80,g0,b0), (0x7F,g1,b1)) and dot3_rgb((0x80,g0,b0), (0x80,g1,b1)) give
// different results.
int result = ((input[0].r() * 2 - 255) * (input[1].r() * 2 - 255) + 128) / 256 +
((input[0].g() * 2 - 255) * (input[1].g() * 2 - 255) + 128) / 256 +
((input[0].b() * 2 - 255) * (input[1].b() * 2 - 255) + 128) / 256;
result = std::max(0, std::min(255, result));
return {(u8)result, (u8)result, (u8)result};
}
default:
LOG_ERROR(HW_GPU, "Unknown color combiner operation %d", (int)op);
UNIMPLEMENTED();
return {0, 0, 0};
}
};
u8 AlphaCombine(TevStageConfig::Operation op, const std::array<u8, 3>& input) {
switch (op) {
using Operation = TevStageConfig::Operation;
case Operation::Replace:
return input[0];
case Operation::Modulate:
return input[0] * input[1] / 255;
case Operation::Add:
return std::min(255, input[0] + input[1]);
case Operation::AddSigned: {
// TODO(bunnei): Verify that the color conversion from (float) 0.5f to (byte) 128 is correct
auto result = static_cast<int>(input[0]) + static_cast<int>(input[1]) - 128;
return static_cast<u8>(MathUtil::Clamp<int>(result, 0, 255));
}
case Operation::Lerp:
return (input[0] * input[2] + input[1] * (255 - input[2])) / 255;
case Operation::Subtract:
return std::max(0, (int)input[0] - (int)input[1]);
case Operation::MultiplyThenAdd:
return std::min(255, (input[0] * input[1] + 255 * input[2]) / 255);
case Operation::AddThenMultiply:
return (std::min(255, (input[0] + input[1])) * input[2]) / 255;
default:
LOG_ERROR(HW_GPU, "Unknown alpha combiner operation %d", (int)op);
UNIMPLEMENTED();
return 0;
}
};
} // namespace Rasterizer
} // namespace Pica
