ShuriZma
/
xenia
mirror of https://github.com/xenia-project/xenia.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

[GPU] More exact PWL texture/RT gamma conversion

This commit is contained in:
Triang3l 2022-06-07 21:26:34 +03:00
parent 55a91afcc7
commit 56f72da137
6 changed files with 238 additions and 77 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

173
src/xenia/gpu/dxbc_shader_translator.cc
View File

@ -212,63 +212,124 @@ void DxbcShaderTranslator::PopSystemTemp(uint32_t count) {
system_temp_count_current_ -= std::min(count, system_temp_count_current_);
}
void DxbcShaderTranslator::ConvertPWLGamma(
bool to_gamma, int32_t source_temp, uint32_t source_temp_component,
uint32_t target_temp, uint32_t target_temp_component, uint32_t piece_temp,
uint32_t piece_temp_component, uint32_t accumulator_temp,
uint32_t accumulator_temp_component) {
assert_true(source_temp != target_temp ||
source_temp_component != target_temp_component ||
((target_temp != accumulator_temp ||
target_temp_component != accumulator_temp_component) &&
(target_temp != piece_temp ||
target_temp_component != piece_temp_component)));
assert_true(piece_temp != source_temp ||
piece_temp_component != source_temp_component);
assert_true(accumulator_temp != source_temp ||
accumulator_temp_component != source_temp_component);
assert_true(piece_temp != accumulator_temp ||
piece_temp_component != accumulator_temp_component);
void DxbcShaderTranslator::PWLGammaToLinear(
uint32_t target_temp, uint32_t target_temp_component, uint32_t source_temp,
uint32_t source_temp_component, bool source_pre_saturated, uint32_t temp1,
uint32_t temp1_component, uint32_t temp2, uint32_t temp2_component) {
// The source is needed only once to begin building the result, so it can be
// the same as the destination.
assert_true(temp1 != target_temp || temp1_component != target_temp_component);
assert_true(temp1 != source_temp || temp1_component != source_temp_component);
assert_true(temp2 != target_temp || temp2_component != target_temp_component);
assert_true(temp2 != source_temp || temp2_component != source_temp_component);
assert_true(temp1 != temp2 || temp1_component != temp2_component);
dxbc::Dest target_dest(
dxbc::Dest::R(target_temp, UINT32_C(1) << target_temp_component));
dxbc::Src target_src(dxbc::Src::R(target_temp).Select(target_temp_component));
dxbc::Src source_src(dxbc::Src::R(source_temp).Select(source_temp_component));
dxbc::Dest piece_dest(dxbc::Dest::R(piece_temp, 1 << piece_temp_component));
dxbc::Src piece_src(dxbc::Src::R(piece_temp).Select(piece_temp_component));
dxbc::Dest accumulator_dest(
dxbc::Dest::R(accumulator_temp, 1 << accumulator_temp_component));
dxbc::Src accumulator_src(
dxbc::Src::R(accumulator_temp).Select(accumulator_temp_component));
// For each piece:
// 1) Calculate how far we are on it. Multiply by 1/width, subtract
// start/width and saturate.
// 2) Add the contribution of the piece - multiply the position on the piece
// by its slope*width and accumulate.
// Piece 1.
a_.OpMul(piece_dest, source_src,
dxbc::Src::LF(to_gamma ? (1.0f / 0.0625f) : (1.0f / 0.25f)), true);
a_.OpMul(accumulator_dest, piece_src,
dxbc::Src::LF(to_gamma ? (4.0f * 0.0625f) : (0.25f * 0.25f)));
// Piece 2.
a_.OpMAd(piece_dest, source_src,
dxbc::Src::LF(to_gamma ? (1.0f / 0.0625f) : (1.0f / 0.125f)),
dxbc::Src::LF(to_gamma ? (-0.0625f / 0.0625f) : (-0.25f / 0.125f)),
true);
a_.OpMAd(accumulator_dest, piece_src,
dxbc::Src::LF(to_gamma ? (2.0f * 0.0625f) : (0.5f * 0.125f)),
accumulator_src);
// Piece 3.
a_.OpMAd(piece_dest, source_src,
dxbc::Src::LF(to_gamma ? (1.0f / 0.375f) : (1.0f / 0.375f)),
dxbc::Src::LF(to_gamma ? (-0.125f / 0.375f) : (-0.375f / 0.375f)),
true);
a_.OpMAd(accumulator_dest, piece_src,
dxbc::Src::LF(to_gamma ? (1.0f * 0.375f) : (1.0f * 0.375f)),
accumulator_src);
// Piece 4.
a_.OpMAd(piece_dest, source_src,
dxbc::Src::LF(to_gamma ? (1.0f / 0.5f) : (1.0f / 0.25f)),
dxbc::Src::LF(to_gamma ? (-0.5f / 0.5f) : (-0.75f / 0.25f)), true);
a_.OpMAd(dxbc::Dest::R(target_temp, 1 << target_temp_component), piece_src,
dxbc::Src::LF(to_gamma ? (0.5f * 0.5f) : (2.0f * 0.25f)),
accumulator_src);
dxbc::Dest temp1_dest(dxbc::Dest::R(temp1, UINT32_C(1) << temp1_component));
dxbc::Src temp1_src(dxbc::Src::R(temp1).Select(temp1_component));
dxbc::Dest temp2_dest(dxbc::Dest::R(temp2, UINT32_C(1) << temp2_component));
dxbc::Src temp2_src(dxbc::Src::R(temp2).Select(temp2_component));
// Get the scale (into temp1) and the offset (into temp2) for the piece.
// Using `source >= threshold` comparisons because the input might have not
// been saturated yet, and thus it may be NaN - since it will be saturated to
// 0 later, the 0...64/255 case should be selected for it.
a_.OpGE(temp2_dest, source_src, dxbc::Src::LF(96.0f / 255.0f));
a_.OpIf(true, temp2_src);
// [96/255 ... 1
a_.OpGE(temp2_dest, source_src, dxbc::Src::LF(192.0f / 255.0f));
a_.OpMovC(temp1_dest, temp2_src, dxbc::Src::LF(8.0f / 1024.0f),
dxbc::Src::LF(4.0f / 1024.0f));
a_.OpMovC(temp2_dest, temp2_src, dxbc::Src::LF(-1024.0f),
dxbc::Src::LF(-256.0f));
a_.OpElse();
// 0 ... 96/255)
a_.OpGE(temp2_dest, source_src, dxbc::Src::LF(64.0f / 255.0f));
a_.OpMovC(temp1_dest, temp2_src, dxbc::Src::LF(2.0f / 1024.0f),
dxbc::Src::LF(1.0f / 1024.0f));
a_.OpMovC(temp2_dest, temp2_src, dxbc::Src::LF(-64.0f), dxbc::Src::LF(0.0f));
a_.OpEndIf();
if (!source_pre_saturated) {
// Saturate the input, and flush NaN to 0.
a_.OpMov(target_dest, source_src, true);
}
// linear = gamma * (255 * 1024) * scale + offset
// As both 1024 and the scale are powers of 2, and 1024 * scale is not smaller
// than 1, it's not important if it's (gamma * 255) * 1024 * scale,
// (gamma * 255 * 1024) * scale, gamma * 255 * (1024 * scale), or
// gamma * (255 * 1024 * scale) - or the option chosen here, as long as
// 1024 is applied before the scale since the scale is < 1 (specifically at
// least 1/1024), and it may make very small values denormal.
a_.OpMul(target_dest, source_pre_saturated ? source_src : target_src,
dxbc::Src::LF(255.0f * 1024.0f));
a_.OpMAd(target_dest, target_src, temp1_src, temp2_src);
// linear += trunc(linear * scale)
a_.OpMul(temp1_dest, target_src, temp1_src);
a_.OpRoundZ(temp1_dest, temp1_src);
a_.OpAdd(target_dest, target_src, temp1_src);
// linear *= 1/1023
a_.OpMul(target_dest, target_src, dxbc::Src::LF(1.0f / 1023.0f));
}
void DxbcShaderTranslator::PreSaturatedLinearToPWLGamma(
uint32_t target_temp, uint32_t target_temp_component, uint32_t source_temp,
uint32_t source_temp_component, uint32_t temp_or_target,
uint32_t temp_or_target_component, uint32_t temp_non_target,
uint32_t temp_non_target_component) {
// The source may be the same as the target, but in this case it can't also be
// used as a temporary variable.
assert_true(target_temp != source_temp ||
target_temp_component != source_temp_component ||
target_temp != temp_or_target ||
target_temp_component != temp_or_target_component);
assert_true(temp_or_target != source_temp ||
temp_or_target_component != source_temp_component);
assert_true(temp_non_target != target_temp ||
temp_non_target_component != target_temp_component);
assert_true(temp_non_target != source_temp ||
temp_non_target_component != source_temp_component);
assert_true(temp_or_target != temp_non_target ||
temp_or_target_component != temp_non_target_component);
dxbc::Dest target_dest(
dxbc::Dest::R(target_temp, UINT32_C(1) << target_temp_component));
dxbc::Src target_src(dxbc::Src::R(target_temp).Select(target_temp_component));
dxbc::Src source_src(dxbc::Src::R(source_temp).Select(source_temp_component));
dxbc::Dest temp_or_target_dest(
dxbc::Dest::R(temp_or_target, UINT32_C(1) << temp_or_target_component));
dxbc::Src temp_or_target_src(
dxbc::Src::R(temp_or_target).Select(temp_or_target_component));
dxbc::Dest temp_non_target_dest(
dxbc::Dest::R(temp_non_target, UINT32_C(1) << temp_non_target_component));
dxbc::Src temp_non_target_src(
dxbc::Src::R(temp_non_target).Select(temp_non_target_component));
// Get the scale (into temp_or_target) and the offset (into temp_non_target)
// for the piece.
a_.OpGE(temp_non_target_dest, source_src, dxbc::Src::LF(128.0f / 1023.0f));
a_.OpIf(true, temp_non_target_src);
// [128/1023 ... 1
a_.OpGE(temp_non_target_dest, source_src, dxbc::Src::LF(512.0f / 1023.0f));
a_.OpMovC(temp_or_target_dest, temp_non_target_src,
dxbc::Src::LF(1023.0f / 8.0f), dxbc::Src::LF(1023.0f / 4.0f));
a_.OpMovC(temp_non_target_dest, temp_non_target_src,
dxbc::Src::LF(128.0f / 255.0f), dxbc::Src::LF(64.0f / 255.0f));
a_.OpElse();
// 0 ... 128/1023)
a_.OpGE(temp_non_target_dest, source_src, dxbc::Src::LF(64.0f / 1023.0f));
a_.OpMovC(temp_or_target_dest, temp_non_target_src,
dxbc::Src::LF(1023.0f / 2.0f), dxbc::Src::LF(1023.0f));
a_.OpMovC(temp_non_target_dest, temp_non_target_src,
dxbc::Src::LF(32.0f / 255.0f), dxbc::Src::LF(0.0f));
a_.OpEndIf();
// gamma = trunc(linear * scale) * (1.0 / 255.0) + offset
a_.OpMul(target_dest, source_src, temp_or_target_src);
a_.OpRoundZ(target_dest, target_src);
a_.OpMAd(target_dest, target_src, dxbc::Src::LF(1.0f / 255.0f),
temp_non_target_src);
}
void DxbcShaderTranslator::RemapAndConvertVertexIndices(

26
src/xenia/gpu/dxbc_shader_translator.h
View File

@ -664,15 +664,23 @@ class DxbcShaderTranslator : public ShaderTranslator {
// Frees the last allocated internal r# registers for later reuse.
void PopSystemTemp(uint32_t count = 1);
// Converts one scalar to or from PWL gamma, using 1 temporary scalar.
// The target may be the same as any of the source, the piece temporary or the
// accumulator, but not two or three of these.
// The piece and the accumulator can't be the same as source or as each other.
void ConvertPWLGamma(bool to_gamma, int32_t source_temp,
uint32_t source_temp_component, uint32_t target_temp,
uint32_t target_temp_component, uint32_t piece_temp,
uint32_t piece_temp_component, uint32_t accumulator_temp,
uint32_t accumulator_temp_component);
// Converts one scalar from piecewise linear gamma to linear. The target may
// be the same as the source, the temporary variables must be different. If
// the source is not pre-saturated, saturation will be done internally.
void PWLGammaToLinear(uint32_t target_temp, uint32_t target_temp_component,
uint32_t source_temp, uint32_t source_temp_component,
bool source_pre_saturated, uint32_t temp1,
uint32_t temp1_component, uint32_t temp2,
uint32_t temp2_component);
// Converts one scalar, which must be saturated before calling this function,
// from linear to piecewise linear gamma. The target may be the same as either
// the source or as temp_or_target, but not as both (and temp_or_target may
// not be the same as the source). temp_non_target must be different.
void PreSaturatedLinearToPWLGamma(
uint32_t target_temp, uint32_t target_temp_component,
uint32_t source_temp, uint32_t source_temp_component,
uint32_t temp_or_target, uint32_t temp_or_target_component,
uint32_t temp_non_target, uint32_t temp_non_target_component);
bool IsSampleRate() const {
assert_true(is_pixel_shader());

4
src/xenia/gpu/dxbc_shader_translator_fetch.cc
View File

@ -2103,8 +2103,8 @@ void DxbcShaderTranslator::ProcessTextureFetchInstruction(
a_.OpIf(false, dxbc::Src::R(gamma_temp, dxbc::Src::kXXXX));
}
// Convert from piecewise linear.
ConvertPWLGamma(false, system_temp_result_, i, system_temp_result_, i,
gamma_temp, 0, gamma_temp, 1);
PWLGammaToLinear(system_temp_result_, i, system_temp_result_, i, false,
gamma_temp, 0, gamma_temp, 1);
if (gamma_render_target_as_srgb_) {
a_.OpElse();
// Convert from sRGB.

24
src/xenia/gpu/dxbc_shader_translator_om.cc
View File

@ -1384,8 +1384,8 @@ void DxbcShaderTranslator::ROV_UnpackColor(
dxbc::Src::LF(1.0f / 255.0f));
if (i) {
for (uint32_t j = 0; j < 3; ++j) {
ConvertPWLGamma(false, color_temp, j, color_temp, j, temp1,
temp1_component, temp2, temp2_component);
PWLGammaToLinear(color_temp, j, color_temp, j, true, temp1,
temp1_component, temp2, temp2_component);
}
}
a_.OpBreak();
@ -1537,8 +1537,9 @@ void DxbcShaderTranslator::ROV_PackPreClampedColor(
: xenos::ColorRenderTargetFormat::k_8_8_8_8)));
for (uint32_t j = 0; j < 4; ++j) {
if (i && j < 3) {
ConvertPWLGamma(true, color_temp, j, temp1, temp1_component, temp1,
temp1_component, temp2, temp2_component);
PreSaturatedLinearToPWLGamma(temp1, temp1_component, color_temp, j,
temp1, temp1_component, temp2,
temp2_component);
// Denormalize and add 0.5 for rounding.
a_.OpMAd(temp1_dest, temp1_src, dxbc::Src::LF(255.0f),
dxbc::Src::LF(0.5f));
@ -1863,10 +1864,10 @@ void DxbcShaderTranslator::CompletePixelShader_WriteToRTVs() {
if (!(shader_writes_color_targets & (1 << i))) {
continue;
}
uint32_t system_temp_color = system_temps_color_[i];
// Apply the exponent bias after alpha to coverage because it needs the
// unbiased alpha from the shader
a_.OpMul(dxbc::Dest::R(system_temps_color_[i]),
dxbc::Src::R(system_temps_color_[i]),
// unbiased alpha from the shader.
a_.OpMul(dxbc::Dest::R(system_temp_color), dxbc::Src::R(system_temp_color),
LoadSystemConstant(
SystemConstants::Index::kColorExpBias,
offsetof(SystemConstants, color_exp_bias) + sizeof(float) * i,
@ -1878,14 +1879,17 @@ void DxbcShaderTranslator::CompletePixelShader_WriteToRTVs() {
a_.OpAnd(dxbc::Dest::R(gamma_temp, 0b0001), LoadFlagsSystemConstant(),
dxbc::Src::LU(kSysFlag_ConvertColor0ToGamma << i));
a_.OpIf(true, dxbc::Src::R(gamma_temp, dxbc::Src::kXXXX));
// Saturate before the gamma conversion.
a_.OpMov(dxbc::Dest::R(system_temp_color, 0b0111),
dxbc::Src::R(system_temp_color), true);
for (uint32_t j = 0; j < 3; ++j) {
ConvertPWLGamma(true, system_temps_color_[i], j, system_temps_color_[i],
j, gamma_temp, 0, gamma_temp, 1);
PreSaturatedLinearToPWLGamma(system_temp_color, j, system_temp_color, j,
gamma_temp, 0, gamma_temp, 1);
}
a_.OpEndIf();
}
// Copy the color from a readable temp register to an output register.
a_.OpMov(dxbc::Dest::O(i), dxbc::Src::R(system_temps_color_[i]));
a_.OpMov(dxbc::Dest::O(i), dxbc::Src::R(system_temp_color));
}
// Release gamma_temp.
PopSystemTemp();

85
src/xenia/gpu/xenos.cc
View File

@ -17,6 +17,91 @@ namespace xe {
namespace gpu {
namespace xenos {
// Based on X360GammaToLinear and X360LinearToGamma from the Source Engine, with
// additional logic from Direct3D 9 code in game executable disassembly, located
// via the floating-point constants involved.
// https://github.com/ValveSoftware/source-sdk-2013/blob/master/mp/src/mathlib/color_conversion.cpp#L329
// These are provided here in part as a reference for shader translators.
float PWLGammaToLinear(float gamma) {
// Not found in game executables, so just using the logic similar to that in
// the Source Engine.
gamma = xe::saturate_unsigned(gamma);
float scale, offset;
// While the compiled code for linear to gamma conversion uses `vcmpgtfp
// constant, value` comparison (constant > value, or value < constant), it's
// preferable to use `value >= constant` condition for the higher pieces, as
// it will never pass for NaN, and in case of NaN, the 0...64/255 case will be
// selected regardless of whether it's saturated before or after the
// comparisons (always pre-saturating here, but shader translators may choose
// to saturate later for convenience), as saturation will flush NaN to 0.
if (gamma >= 96.0f / 255.0f) {
if (gamma >= 192.0f / 255.0f) {
scale = 8.0f / 1024.0f;
offset = -1024.0f;
} else {
scale = 4.0f / 1024.0f;
offset = -256.0f;
}
} else {
if (gamma >= 64.0f / 255.0f) {
scale = 2.0f / 1024.0f;
offset = -64.0f;
} else {
scale = 1.0f / 1024.0f;
offset = 0.0f;
// No `floor` term in this case in the Source Engine, but for the largest
// value, 1.0, `floor(255.0f * (1.0f / 1024.0f))` is 0 anyway.
}
}
// Though in the Source Engine, the 1/1024 multiplication is done for the
// truncated part specifically, pre-baking it into the scale is lossless -
// both 1024 and `scale` are powers of 2.
float linear = gamma * ((255.0f * 1024.0f) * scale) + offset;
// For consistency with linear to gamma, and because it's more logical here
// (0 rather than 1 at -epsilon), using `trunc` instead of `floor`.
linear += std::trunc(linear * scale);
linear *= 1.0f / 1023.0f;
// Clamping is not necessary (1 * (255 * 8) - 1024 + 7 is exactly 1023).
return linear;
}
float LinearToPWLGamma(float linear) {
linear = xe::saturate_unsigned(linear);
float scale, offset;
// While the compiled code uses `vcmpgtfp constant, value` comparison
// (constant > value, or value < constant), it's preferable to use `value >=
// constant` condition for the higher pieces, as it will never pass for NaN,
// and in case of NaN, the 0...64/1023 case will be selected regardless of
// whether it's saturated before or after the comparisons (always
// pre-saturating here, but shader translators may choose to saturate later
// for convenience), as saturation will flush NaN to 0.
if (linear >= 128.0f / 1023.0f) {
if (linear >= 512.0f / 1023.0f) {
scale = 1023.0f / 8.0f;
offset = 128.0f / 255.0f;
} else {
scale = 1023.0f / 4.0f;
offset = 64.0f / 255.0f;
}
} else {
if (linear >= 64.0f / 1023.0f) {
scale = 1023.0f / 2.0f;
offset = 32.0f / 255.0f;
} else {
scale = 1023.0f;
offset = 0.0f;
}
}
// The truncation isn't in X360LinearToGamma in the Source Engine, but is
// there in Direct3D 9 disassembly (the `vrfiz` instructions).
// It also prevents conversion of 1.0 to 1.0034313725490196078431372549016
// that's handled via clamping in the Source Engine.
// 127.875 (1023 / 8) is truncated to 127, which, after scaling, becomes
// 127 / 255, and when 128 / 255 is added, the result is 1.
return std::trunc(linear * scale) * (1.0f / 255.0f) + offset;
}
// https://github.com/Microsoft/DirectXTex/blob/master/DirectXTex/DirectXTexConvert.cpp
float Float7e3To32(uint32_t f10) {

3
src/xenia/gpu/xenos.h
View File

@ -327,6 +327,9 @@ enum class DepthRenderTargetFormat : uint32_t {
const char* GetDepthRenderTargetFormatName(DepthRenderTargetFormat format);
float PWLGammaToLinear(float gamma);
float LinearToPWLGamma(float linear);
// Converts Xenos floating-point 7e3 color value in bits 0:9 (not clamping) to
// an IEEE-754 32-bit floating-point number.
float Float7e3To32(uint32_t f10);