// Copyright 2015 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <array>
#include <cstddef>
#include <cstring>
#include "common/assert.h"
#include "common/bit_field.h"
#include "common/logging/log.h"
#include "video_core/regs_framebuffer.h"
#include "video_core/regs_lighting.h"
#include "video_core/regs_rasterizer.h"
#include "video_core/regs_texturing.h"
#include "video_core/renderer_opengl/gl_rasterizer.h"
#include "video_core/renderer_opengl/gl_shader_gen.h"
#include "video_core/renderer_opengl/gl_shader_util.h"
using Pica::FramebufferRegs;
using Pica::LightingRegs;
using Pica::RasterizerRegs;
using Pica::TexturingRegs;
using TevStageConfig = TexturingRegs::TevStageConfig;
namespace GLShader {
PicaShaderConfig PicaShaderConfig::BuildFromRegs(const Pica::Regs& regs) {
PicaShaderConfig res;
auto& state = res.state;
std::memset(&state, 0, sizeof(PicaShaderConfig::State));
state.scissor_test_mode = regs.rasterizer.scissor_test.mode;
state.depthmap_enable = regs.rasterizer.depthmap_enable;
state.alpha_test_func = regs.framebuffer.output_merger.alpha_test.enable
? regs.framebuffer.output_merger.alpha_test.func.Value()
: Pica::FramebufferRegs::CompareFunc::Always;
state.texture0_type = regs.texturing.texture0.type;
state.texture2_use_coord1 = regs.texturing.main_config.texture2_use_coord1 != 0;
// Copy relevant tev stages fields.
// We don't sync const_color here because of the high variance, it is a
// shader uniform instead.
const auto& tev_stages = regs.texturing.GetTevStages();
DEBUG_ASSERT(state.tev_stages.size() == tev_stages.size());
for (size_t i = 0; i < tev_stages.size(); i++) {
const auto& tev_stage = tev_stages[i];
state.tev_stages[i].sources_raw = tev_stage.sources_raw;
state.tev_stages[i].modifiers_raw = tev_stage.modifiers_raw;
state.tev_stages[i].ops_raw = tev_stage.ops_raw;
state.tev_stages[i].scales_raw = tev_stage.scales_raw;
}
state.fog_mode = regs.texturing.fog_mode;
state.fog_flip = regs.texturing.fog_flip != 0;
state.combiner_buffer_input = regs.texturing.tev_combiner_buffer_input.update_mask_rgb.Value() |
regs.texturing.tev_combiner_buffer_input.update_mask_a.Value()
<< 4;
// Fragment lighting
state.lighting.enable = !regs.lighting.disable;
state.lighting.src_num = regs.lighting.max_light_index + 1;
for (unsigned light_index = 0; light_index < state.lighting.src_num; ++light_index) {
unsigned num = regs.lighting.light_enable.GetNum(light_index);
const auto& light = regs.lighting.light[num];
state.lighting.light[light_index].num = num;
state.lighting.light[light_index].directional = light.config.directional != 0;
state.lighting.light[light_index].two_sided_diffuse = light.config.two_sided_diffuse != 0;
state.lighting.light[light_index].dist_atten_enable =
!regs.lighting.IsDistAttenDisabled(num);
}
state.lighting.lut_d0.enable = regs.lighting.config1.disable_lut_d0 == 0;
state.lighting.lut_d0.abs_input = regs.lighting.abs_lut_input.disable_d0 == 0;
state.lighting.lut_d0.type = regs.lighting.lut_input.d0.Value();
state.lighting.lut_d0.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.d0);
state.lighting.lut_d1.enable = regs.lighting.config1.disable_lut_d1 == 0;
state.lighting.lut_d1.abs_input = regs.lighting.abs_lut_input.disable_d1 == 0;
state.lighting.lut_d1.type = regs.lighting.lut_input.d1.Value();
state.lighting.lut_d1.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.d1);
state.lighting.lut_fr.enable = regs.lighting.config1.disable_lut_fr == 0;
state.lighting.lut_fr.abs_input = regs.lighting.abs_lut_input.disable_fr == 0;
state.lighting.lut_fr.type = regs.lighting.lut_input.fr.Value();
state.lighting.lut_fr.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.fr);
state.lighting.lut_rr.enable = regs.lighting.config1.disable_lut_rr == 0;
state.lighting.lut_rr.abs_input = regs.lighting.abs_lut_input.disable_rr == 0;
state.lighting.lut_rr.type = regs.lighting.lut_input.rr.Value();
state.lighting.lut_rr.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.rr);
state.lighting.lut_rg.enable = regs.lighting.config1.disable_lut_rg == 0;
state.lighting.lut_rg.abs_input = regs.lighting.abs_lut_input.disable_rg == 0;
state.lighting.lut_rg.type = regs.lighting.lut_input.rg.Value();
state.lighting.lut_rg.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.rg);
state.lighting.lut_rb.enable = regs.lighting.config1.disable_lut_rb == 0;
state.lighting.lut_rb.abs_input = regs.lighting.abs_lut_input.disable_rb == 0;
state.lighting.lut_rb.type = regs.lighting.lut_input.rb.Value();
state.lighting.lut_rb.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.rb);
state.lighting.config = regs.lighting.config0.config;
state.lighting.fresnel_selector = regs.lighting.config0.fresnel_selector;
state.lighting.bump_mode = regs.lighting.config0.bump_mode;
state.lighting.bump_selector = regs.lighting.config0.bump_selector;
state.lighting.bump_renorm = regs.lighting.config0.disable_bump_renorm == 0;
state.lighting.clamp_highlights = regs.lighting.config0.clamp_highlights != 0;
state.proctex.enable = regs.texturing.main_config.texture3_enable;
if (state.proctex.enable) {
state.proctex.coord = regs.texturing.main_config.texture3_coordinates;
state.proctex.u_clamp = regs.texturing.proctex.u_clamp;
state.proctex.v_clamp = regs.texturing.proctex.v_clamp;
state.proctex.color_combiner = regs.texturing.proctex.color_combiner;
state.proctex.alpha_combiner = regs.texturing.proctex.alpha_combiner;
state.proctex.separate_alpha = regs.texturing.proctex.separate_alpha;
state.proctex.noise_enable = regs.texturing.proctex.noise_enable;
state.proctex.u_shift = regs.texturing.proctex.u_shift;
state.proctex.v_shift = regs.texturing.proctex.v_shift;
state.proctex.lut_width = regs.texturing.proctex_lut.width;
state.proctex.lut_offset = regs.texturing.proctex_lut_offset;
state.proctex.lut_filter = regs.texturing.proctex_lut.filter;
}
return res;
}
/// Detects if a TEV stage is configured to be skipped (to avoid generating unnecessary code)
static bool IsPassThroughTevStage(const TevStageConfig& stage) {
return (stage.color_op == TevStageConfig::Operation::Replace &&
stage.alpha_op == TevStageConfig::Operation::Replace &&
stage.color_source1 == TevStageConfig::Source::Previous &&
stage.alpha_source1 == TevStageConfig::Source::Previous &&
stage.color_modifier1 == TevStageConfig::ColorModifier::SourceColor &&
stage.alpha_modifier1 == TevStageConfig::AlphaModifier::SourceAlpha &&
stage.GetColorMultiplier() == 1 && stage.GetAlphaMultiplier() == 1);
}
static std::string TexCoord(const PicaShaderConfig& config, int texture_unit) {
if (texture_unit == 2 && config.state.texture2_use_coord1) {
return "texcoord[1]";
}
return "texcoord[" + std::to_string(texture_unit) + "]";
}
/// Writes the specified TEV stage source component(s)
static void AppendSource(std::string& out, const PicaShaderConfig& config,
TevStageConfig::Source source, const std::string& index_name) {
const auto& state = config.state;
using Source = TevStageConfig::Source;
switch (source) {
case Source::PrimaryColor:
out += "primary_color";
break;
case Source::PrimaryFragmentColor:
out += "primary_fragment_color";
break;
case Source::SecondaryFragmentColor:
out += "secondary_fragment_color";
break;
case Source::Texture0:
// Only unit 0 respects the texturing type (according to 3DBrew)
switch (state.texture0_type) {
case TexturingRegs::TextureConfig::Texture2D:
out += "texture(tex[0], texcoord[0])";
break;
case TexturingRegs::TextureConfig::Projection2D:
out += "textureProj(tex[0], vec3(texcoord[0], texcoord0_w))";
break;
default:
out += "texture(tex[0], texcoord[0])";
LOG_CRITICAL(HW_GPU, "Unhandled texture type %x",
static_cast<int>(state.texture0_type));
UNIMPLEMENTED();
break;
}
break;
case Source::Texture1:
out += "texture(tex[1], texcoord[1])";
break;
case Source::Texture2:
out += "texture(tex[2], " + TexCoord(config, 2) + ")";
break;
case Source::Texture3:
if (config.state.proctex.enable) {
out += "ProcTex()";
} else {
LOG_ERROR(Render_OpenGL, "Using Texture3 without enabling it");
out += "vec4(0.0)";
}
break;
case Source::PreviousBuffer:
out += "combiner_buffer";
break;
case Source::Constant:
((out += "const_color[") += index_name) += ']';
break;
case Source::Previous:
out += "last_tex_env_out";
break;
default:
out += "vec4(0.0)";
LOG_CRITICAL(Render_OpenGL, "Unknown source op %u", source);
break;
}
}
/// Writes the color components to use for the specified TEV stage color modifier
static void AppendColorModifier(std::string& out, const PicaShaderConfig& config,
TevStageConfig::ColorModifier modifier,
TevStageConfig::Source source, const std::string& index_name) {
using ColorModifier = TevStageConfig::ColorModifier;
switch (modifier) {
case ColorModifier::SourceColor:
AppendSource(out, config, source, index_name);
out += ".rgb";
break;
case ColorModifier::OneMinusSourceColor:
out += "vec3(1.0) - ";
AppendSource(out, config, source, index_name);
out += ".rgb";
break;
case ColorModifier::SourceAlpha:
AppendSource(out, config, source, index_name);
out += ".aaa";
break;
case ColorModifier::OneMinusSourceAlpha:
out += "vec3(1.0) - ";
AppendSource(out, config, source, index_name);
out += ".aaa";
break;
case ColorModifier::SourceRed:
AppendSource(out, config, source, index_name);
out += ".rrr";
break;
case ColorModifier::OneMinusSourceRed:
out += "vec3(1.0) - ";
AppendSource(out, config, source, index_name);
out += ".rrr";
break;
case ColorModifier::SourceGreen:
AppendSource(out, config, source, index_name);
out += ".ggg";
break;
case ColorModifier::OneMinusSourceGreen:
out += "vec3(1.0) - ";
AppendSource(out, config, source, index_name);
out += ".ggg";
break;
case ColorModifier::SourceBlue:
AppendSource(out, config, source, index_name);
out += ".bbb";
break;
case ColorModifier::OneMinusSourceBlue:
out += "vec3(1.0) - ";
AppendSource(out, config, source, index_name);
out += ".bbb";
break;
default:
out += "vec3(0.0)";
LOG_CRITICAL(Render_OpenGL, "Unknown color modifier op %u", modifier);
break;
}
}
/// Writes the alpha component to use for the specified TEV stage alpha modifier
static void AppendAlphaModifier(std::string& out, const PicaShaderConfig& config,
TevStageConfig::AlphaModifier modifier,
TevStageConfig::Source source, const std::string& index_name) {
using AlphaModifier = TevStageConfig::AlphaModifier;
switch (modifier) {
case AlphaModifier::SourceAlpha:
AppendSource(out, config, source, index_name);
out += ".a";
break;
case AlphaModifier::OneMinusSourceAlpha:
out += "1.0 - ";
AppendSource(out, config, source, index_name);
out += ".a";
break;
case AlphaModifier::SourceRed:
AppendSource(out, config, source, index_name);
out += ".r";
break;
case AlphaModifier::OneMinusSourceRed:
out += "1.0 - ";
AppendSource(out, config, source, index_name);
out += ".r";
break;
case AlphaModifier::SourceGreen:
AppendSource(out, config, source, index_name);
out += ".g";
break;
case AlphaModifier::OneMinusSourceGreen:
out += "1.0 - ";
AppendSource(out, config, source, index_name);
out += ".g";
break;
case AlphaModifier::SourceBlue:
AppendSource(out, config, source, index_name);
out += ".b";
break;
case AlphaModifier::OneMinusSourceBlue:
out += "1.0 - ";
AppendSource(out, config, source, index_name);
out += ".b";
break;
default:
out += "0.0";
LOG_CRITICAL(Render_OpenGL, "Unknown alpha modifier op %u", modifier);
break;
}
}
/// Writes the combiner function for the color components for the specified TEV stage operation
static void AppendColorCombiner(std::string& out, TevStageConfig::Operation operation,
const std::string& variable_name) {
out += "clamp(";
using Operation = TevStageConfig::Operation;
switch (operation) {
case Operation::Replace:
out += variable_name + "[0]";
break;
case Operation::Modulate:
out += variable_name + "[0] * " + variable_name + "[1]";
break;
case Operation::Add:
out += variable_name + "[0] + " + variable_name + "[1]";
break;
case Operation::AddSigned:
out += variable_name + "[0] + " + variable_name + "[1] - vec3(0.5)";
break;
case Operation::Lerp:
out += variable_name + "[0] * " + variable_name + "[2] + " + variable_name +
"[1] * (vec3(1.0) - " + variable_name + "[2])";
break;
case Operation::Subtract:
out += variable_name + "[0] - " + variable_name + "[1]";
break;
case Operation::MultiplyThenAdd:
out += variable_name + "[0] * " + variable_name + "[1] + " + variable_name + "[2]";
break;
case Operation::AddThenMultiply:
out += "min(" + variable_name + "[0] + " + variable_name + "[1], vec3(1.0)) * " +
variable_name + "[2]";
break;
case Operation::Dot3_RGB:
case Operation::Dot3_RGBA:
out += "vec3(dot(" + variable_name + "[0] - vec3(0.5), " + variable_name +
"[1] - vec3(0.5)) * 4.0)";
break;
default:
out += "vec3(0.0)";
LOG_CRITICAL(Render_OpenGL, "Unknown color combiner operation: %u", operation);
break;
}
out += ", vec3(0.0), vec3(1.0))"; // Clamp result to 0.0, 1.0
}
/// Writes the combiner function for the alpha component for the specified TEV stage operation
static void AppendAlphaCombiner(std::string& out, TevStageConfig::Operation operation,
const std::string& variable_name) {
out += "clamp(";
using Operation = TevStageConfig::Operation;
switch (operation) {
case Operation::Replace:
out += variable_name + "[0]";
break;
case Operation::Modulate:
out += variable_name + "[0] * " + variable_name + "[1]";
break;
case Operation::Add:
out += variable_name + "[0] + " + variable_name + "[1]";
break;
case Operation::AddSigned:
out += variable_name + "[0] + " + variable_name + "[1] - 0.5";
break;
case Operation::Lerp:
out += variable_name + "[0] * " + variable_name + "[2] + " + variable_name +
"[1] * (1.0 - " + variable_name + "[2])";
break;
case Operation::Subtract:
out += variable_name + "[0] - " + variable_name + "[1]";
break;
case Operation::MultiplyThenAdd:
out += variable_name + "[0] * " + variable_name + "[1] + " + variable_name + "[2]";
break;
case Operation::AddThenMultiply:
out += "min(" + variable_name + "[0] + " + variable_name + "[1], 1.0) * " + variable_name +
"[2]";
break;
default:
out += "0.0";
LOG_CRITICAL(Render_OpenGL, "Unknown alpha combiner operation: %u", operation);
break;
}
out += ", 0.0, 1.0)";
}
/// Writes the if-statement condition used to evaluate alpha testing
static void AppendAlphaTestCondition(std::string& out, FramebufferRegs::CompareFunc func) {
using CompareFunc = FramebufferRegs::CompareFunc;
switch (func) {
case CompareFunc::Never:
out += "true";
break;
case CompareFunc::Always:
out += "false";
break;
case CompareFunc::Equal:
case CompareFunc::NotEqual:
case CompareFunc::LessThan:
case CompareFunc::LessThanOrEqual:
case CompareFunc::GreaterThan:
case CompareFunc::GreaterThanOrEqual: {
static const char* op[] = {"!=", "==", ">=", ">", "<=", "<"};
unsigned index = (unsigned)func - (unsigned)CompareFunc::Equal;
out += "int(last_tex_env_out.a * 255.0) " + std::string(op[index]) + " alphatest_ref";
break;
}
default:
out += "false";
LOG_CRITICAL(Render_OpenGL, "Unknown alpha test condition %u", func);
break;
}
}
/// Writes the code to emulate the specified TEV stage
static void WriteTevStage(std::string& out, const PicaShaderConfig& config, unsigned index) {
const auto stage =
static_cast<const TexturingRegs::TevStageConfig>(config.state.tev_stages[index]);
if (!IsPassThroughTevStage(stage)) {
std::string index_name = std::to_string(index);
out += "vec3 color_results_" + index_name + "[3] = vec3[3](";
AppendColorModifier(out, config, stage.color_modifier1, stage.color_source1, index_name);
out += ", ";
AppendColorModifier(out, config, stage.color_modifier2, stage.color_source2, index_name);
out += ", ";
AppendColorModifier(out, config, stage.color_modifier3, stage.color_source3, index_name);
out += ");\n";
out += "vec3 color_output_" + index_name + " = ";
AppendColorCombiner(out, stage.color_op, "color_results_" + index_name);
out += ";\n";
if (stage.color_op == TevStageConfig::Operation::Dot3_RGBA) {
// result of Dot3_RGBA operation is also placed to the alpha component
out += "float alpha_output_" + index_name + " = color_output_" + index_name + "[0];\n";
} else {
out += "float alpha_results_" + index_name + "[3] = float[3](";
AppendAlphaModifier(out, config, stage.alpha_modifier1, stage.alpha_source1,
index_name);
out += ", ";
AppendAlphaModifier(out, config, stage.alpha_modifier2, stage.alpha_source2,
index_name);
out += ", ";
AppendAlphaModifier(out, config, stage.alpha_modifier3, stage.alpha_source3,
index_name);
out += ");\n";
out += "float alpha_output_" + index_name + " = ";
AppendAlphaCombiner(out, stage.alpha_op, "alpha_results_" + index_name);
out += ";\n";
}
out += "last_tex_env_out = vec4("
"clamp(color_output_" +
index_name + " * " + std::to_string(stage.GetColorMultiplier()) +
".0, vec3(0.0), vec3(1.0)),"
"clamp(alpha_output_" +
index_name + " * " + std::to_string(stage.GetAlphaMultiplier()) +
".0, 0.0, 1.0));\n";
}
out += "combiner_buffer = next_combiner_buffer;\n";
if (config.TevStageUpdatesCombinerBufferColor(index))
out += "next_combiner_buffer.rgb = last_tex_env_out.rgb;\n";
if (config.TevStageUpdatesCombinerBufferAlpha(index))
out += "next_combiner_buffer.a = last_tex_env_out.a;\n";
}
/// Writes the code to emulate fragment lighting
static void WriteLighting(std::string& out, const PicaShaderConfig& config) {
const auto& lighting = config.state.lighting;
// Define lighting globals
out += "vec4 diffuse_sum = vec4(0.0, 0.0, 0.0, 1.0);\n"
"vec4 specular_sum = vec4(0.0, 0.0, 0.0, 1.0);\n"
"vec3 light_vector = vec3(0.0);\n"
"vec3 refl_value = vec3(0.0);\n";
// Compute fragment normals
if (lighting.bump_mode == LightingRegs::LightingBumpMode::NormalMap) {
// Bump mapping is enabled using a normal map, read perturbation vector from the selected
// texture
if (lighting.bump_selector == 3) {
if (config.state.proctex.enable) {
out += "vec3 surface_normal = 2.0 * ProcTex().rgb - 1.0;\n";
} else {
LOG_ERROR(Render_OpenGL, "Using Texture3 without enabling it");
out += "vec3 surface_normal = vec3(-1.0);\n";
}
} else {
std::string bump_selector = std::to_string(lighting.bump_selector);
out += "vec3 surface_normal = 2.0 * texture(tex[" + bump_selector + "], " +
TexCoord(config, lighting.bump_selector) + ").rgb - 1.0;\n";
}
// Recompute Z-component of perturbation if 'renorm' is enabled, this provides a higher
// precision result
if (lighting.bump_renorm) {
std::string val =
"(1.0 - (surface_normal.x*surface_normal.x + surface_normal.y*surface_normal.y))";
out += "surface_normal.z = sqrt(max(" + val + ", 0.0));\n";
}
} else if (lighting.bump_mode == LightingRegs::LightingBumpMode::TangentMap) {
// Bump mapping is enabled using a tangent map
LOG_CRITICAL(HW_GPU, "unimplemented bump mapping mode (tangent mapping)");
UNIMPLEMENTED();
} else {
// No bump mapping - surface local normal is just a unit normal
out += "vec3 surface_normal = vec3(0.0, 0.0, 1.0);\n";
}
// Rotate the surface-local normal by the interpolated normal quaternion to convert it to
// eyespace
out += "vec3 normal = normalize(quaternion_rotate(normquat, surface_normal));\n";
// Gets the index into the specified lookup table for specular lighting
auto GetLutIndex = [&lighting](unsigned light_num, LightingRegs::LightingLutInput input,
bool abs) {
const std::string half_angle = "normalize(normalize(view) + light_vector)";
std::string index;
switch (input) {
case LightingRegs::LightingLutInput::NH:
index = "dot(normal, " + half_angle + ")";
break;
case LightingRegs::LightingLutInput::VH:
index = std::string("dot(normalize(view), " + half_angle + ")");
break;
case LightingRegs::LightingLutInput::NV:
index = std::string("dot(normal, normalize(view))");
break;
case LightingRegs::LightingLutInput::LN:
index = std::string("dot(light_vector, normal)");
break;
default:
LOG_CRITICAL(HW_GPU, "Unknown lighting LUT input %d\n", (int)input);
UNIMPLEMENTED();
index = "0.0";
break;
}
if (abs) {
// LUT index is in the range of (0.0, 1.0)
index = lighting.light[light_num].two_sided_diffuse ? "abs(" + index + ")"
: "max(" + index + ", 0.0)";
} else {
// LUT index is in the range of (-1.0, 1.0)
index = "((" + index + " < 0) ? " + index + " + 2.0 : " + index + ") / 2.0";
}
return "(OFFSET_256 + SCALE_256 * clamp(" + index + ", 0.0, 1.0))";
};
// Gets the lighting lookup table value given the specified sampler and index
auto GetLutValue = [](LightingRegs::LightingSampler sampler, std::string lut_index) {
return std::string("texture(lut[" + std::to_string((unsigned)sampler / 4) + "], " +
lut_index + ")[" + std::to_string((unsigned)sampler & 3) + "]");
};
// Write the code to emulate each enabled light
for (unsigned light_index = 0; light_index < lighting.src_num; ++light_index) {
const auto& light_config = lighting.light[light_index];
std::string light_src = "light_src[" + std::to_string(light_config.num) + "]";
// Compute light vector (directional or positional)
if (light_config.directional)
out += "light_vector = normalize(" + light_src + ".position);\n";
else
out += "light_vector = normalize(" + light_src + ".position + view);\n";
// Compute dot product of light_vector and normal, adjust if lighting is one-sided or
// two-sided
std::string dot_product = light_config.two_sided_diffuse
? "abs(dot(light_vector, normal))"
: "max(dot(light_vector, normal), 0.0)";
// If enabled, compute distance attenuation value
std::string dist_atten = "1.0";
if (light_config.dist_atten_enable) {
std::string index = "(" + light_src + ".dist_atten_scale * length(-view - " +
light_src + ".position) + " + light_src + ".dist_atten_bias)";
index = "(OFFSET_256 + SCALE_256 * clamp(" + index + ", 0.0, 1.0))";
const unsigned lut_num =
((unsigned)LightingRegs::LightingSampler::DistanceAttenuation + light_config.num);
dist_atten = GetLutValue((LightingRegs::LightingSampler)lut_num, index);
}
// If enabled, clamp specular component if lighting result is negative
std::string clamp_highlights =
lighting.clamp_highlights ? "(dot(light_vector, normal) <= 0.0 ? 0.0 : 1.0)" : "1.0";
// Specular 0 component
std::string d0_lut_value = "1.0";
if (lighting.lut_d0.enable &&
LightingRegs::IsLightingSamplerSupported(
lighting.config, LightingRegs::LightingSampler::Distribution0)) {
// Lookup specular "distribution 0" LUT value
std::string index =
GetLutIndex(light_config.num, lighting.lut_d0.type, lighting.lut_d0.abs_input);
d0_lut_value = "(" + std::to_string(lighting.lut_d0.scale) + " * " +
GetLutValue(LightingRegs::LightingSampler::Distribution0, index) + ")";
}
std::string specular_0 = "(" + d0_lut_value + " * " + light_src + ".specular_0)";
// If enabled, lookup ReflectRed value, otherwise, 1.0 is used
if (lighting.lut_rr.enable &&
LightingRegs::IsLightingSamplerSupported(lighting.config,
LightingRegs::LightingSampler::ReflectRed)) {
std::string index =
GetLutIndex(light_config.num, lighting.lut_rr.type, lighting.lut_rr.abs_input);
std::string value = "(" + std::to_string(lighting.lut_rr.scale) + " * " +
GetLutValue(LightingRegs::LightingSampler::ReflectRed, index) + ")";
out += "refl_value.r = " + value + ";\n";
} else {
out += "refl_value.r = 1.0;\n";
}
// If enabled, lookup ReflectGreen value, otherwise, ReflectRed value is used
if (lighting.lut_rg.enable &&
LightingRegs::IsLightingSamplerSupported(lighting.config,
LightingRegs::LightingSampler::ReflectGreen)) {
std::string index =
GetLutIndex(light_config.num, lighting.lut_rg.type, lighting.lut_rg.abs_input);
std::string value = "(" + std::to_string(lighting.lut_rg.scale) + " * " +
GetLutValue(LightingRegs::LightingSampler::ReflectGreen, index) +
")";
out += "refl_value.g = " + value + ";\n";
} else {
out += "refl_value.g = refl_value.r;\n";
}
// If enabled, lookup ReflectBlue value, otherwise, ReflectRed value is used
if (lighting.lut_rb.enable &&
LightingRegs::IsLightingSamplerSupported(lighting.config,
LightingRegs::LightingSampler::ReflectBlue)) {
std::string index =
GetLutIndex(light_config.num, lighting.lut_rb.type, lighting.lut_rb.abs_input);
std::string value = "(" + std::to_string(lighting.lut_rb.scale) + " * " +
GetLutValue(LightingRegs::LightingSampler::ReflectBlue, index) +
")";
out += "refl_value.b = " + value + ";\n";
} else {
out += "refl_value.b = refl_value.r;\n";
}
// Specular 1 component
std::string d1_lut_value = "1.0";
if (lighting.lut_d1.enable &&
LightingRegs::IsLightingSamplerSupported(
lighting.config, LightingRegs::LightingSampler::Distribution1)) {
// Lookup specular "distribution 1" LUT value
std::string index =
GetLutIndex(light_config.num, lighting.lut_d1.type, lighting.lut_d1.abs_input);
d1_lut_value = "(" + std::to_string(lighting.lut_d1.scale) + " * " +
GetLutValue(LightingRegs::LightingSampler::Distribution1, index) + ")";
}
std::string specular_1 =
"(" + d1_lut_value + " * refl_value * " + light_src + ".specular_1)";
// Fresnel
if (lighting.lut_fr.enable &&
LightingRegs::IsLightingSamplerSupported(lighting.config,
LightingRegs::LightingSampler::Fresnel)) {
// Lookup fresnel LUT value
std::string index =
GetLutIndex(light_config.num, lighting.lut_fr.type, lighting.lut_fr.abs_input);
std::string value = "(" + std::to_string(lighting.lut_fr.scale) + " * " +
GetLutValue(LightingRegs::LightingSampler::Fresnel, index) + ")";
// Enabled for difffuse lighting alpha component
if (lighting.fresnel_selector == LightingRegs::LightingFresnelSelector::PrimaryAlpha ||
lighting.fresnel_selector == LightingRegs::LightingFresnelSelector::Both) {
out += "diffuse_sum.a *= " + value + ";\n";
}
// Enabled for the specular lighting alpha component
if (lighting.fresnel_selector ==
LightingRegs::LightingFresnelSelector::SecondaryAlpha ||
lighting.fresnel_selector == LightingRegs::LightingFresnelSelector::Both) {
out += "specular_sum.a *= " + value + ";\n";
}
}
// Compute primary fragment color (diffuse lighting) function
out += "diffuse_sum.rgb += ((" + light_src + ".diffuse * " + dot_product + ") + " +
light_src + ".ambient) * " + dist_atten + ";\n";
// Compute secondary fragment color (specular lighting) function
out += "specular_sum.rgb += (" + specular_0 + " + " + specular_1 + ") * " +
clamp_highlights + " * " + dist_atten + ";\n";
}
// Sum final lighting result
out += "diffuse_sum.rgb += lighting_global_ambient;\n";
out += "primary_fragment_color = clamp(diffuse_sum, vec4(0.0), vec4(1.0));\n";
out += "secondary_fragment_color = clamp(specular_sum, vec4(0.0), vec4(1.0));\n";
}
using ProcTexClamp = TexturingRegs::ProcTexClamp;
using ProcTexShift = TexturingRegs::ProcTexShift;
using ProcTexCombiner = TexturingRegs::ProcTexCombiner;
using ProcTexFilter = TexturingRegs::ProcTexFilter;
void AppendProcTexShiftOffset(std::string& out, const std::string& v, ProcTexShift mode,
ProcTexClamp clamp_mode) {
std::string offset = (clamp_mode == ProcTexClamp::MirroredRepeat) ? "1.0" : "0.5";
switch (mode) {
case ProcTexShift::None:
out += "0";
break;
case ProcTexShift::Odd:
out += offset + " * ((int(" + v + ") / 2) % 2)";
break;
case ProcTexShift::Even:
out += offset + " * (((int(" + v + ") + 1) / 2) % 2)";
break;
default:
LOG_CRITICAL(HW_GPU, "Unknown shift mode %u", static_cast<u32>(mode));
out += "0";
break;
}
}
void AppendProcTexClamp(std::string& out, const std::string& var, ProcTexClamp mode) {
switch (mode) {
case ProcTexClamp::ToZero:
out += var + " = " + var + " > 1.0 ? 0 : " + var + ";\n";
break;
case ProcTexClamp::ToEdge:
out += var + " = " + "min(" + var + ", 1.0);\n";
break;
case ProcTexClamp::SymmetricalRepeat:
out += var + " = " + "fract(" + var + ");\n";
break;
case ProcTexClamp::MirroredRepeat: {
out +=
var + " = int(" + var + ") % 2 == 0 ? fract(" + var + ") : 1.0 - fract(" + var + ");\n";
break;
}
case ProcTexClamp::Pulse:
out += var + " = " + var + " > 0.5 ? 1.0 : 0.0;\n";
break;
default:
LOG_CRITICAL(HW_GPU, "Unknown clamp mode %u", static_cast<u32>(mode));
out += var + " = " + "min(" + var + ", 1.0);\n";
break;
}
}
void AppendProcTexCombineAndMap(std::string& out, ProcTexCombiner combiner,
const std::string& map_lut) {
std::string combined;
switch (combiner) {
case ProcTexCombiner::U:
combined = "u";
break;
case ProcTexCombiner::U2:
combined = "(u * u)";
break;
case TexturingRegs::ProcTexCombiner::V:
combined = "v";
break;
case TexturingRegs::ProcTexCombiner::V2:
combined = "(v * v)";
break;
case TexturingRegs::ProcTexCombiner::Add:
combined = "((u + v) * 0.5)";
break;
case TexturingRegs::ProcTexCombiner::Add2:
combined = "((u * u + v * v) * 0.5)";
break;
case TexturingRegs::ProcTexCombiner::SqrtAdd2:
combined = "min(sqrt(u * u + v * v), 1.0)";
break;
case TexturingRegs::ProcTexCombiner::Min:
combined = "min(u, v)";
break;
case TexturingRegs::ProcTexCombiner::Max:
combined = "max(u, v)";
break;
case TexturingRegs::ProcTexCombiner::RMax:
combined = "min(((u + v) * 0.5 + sqrt(u * u + v * v)) * 0.5, 1.0)";
break;
default:
LOG_CRITICAL(HW_GPU, "Unknown combiner %u", static_cast<u32>(combiner));
combined = "0.0";
break;
}
out += "ProcTexLookupLUT(" + map_lut + ", " + combined + ")";
}
void AppendProcTexSampler(std::string& out, const PicaShaderConfig& config) {
// LUT sampling uitlity
// For NoiseLUT/ColorMap/AlphaMap, coord=0.0 is lut[0], coord=127.0/128.0 is lut[127] and
// coord=1.0 is lut[127]+lut_diff[127]. For other indices, the result is interpolated using
// value entries and difference entries.
out += R"(
float ProcTexLookupLUT(sampler1D lut, float coord) {
coord *= 128;
float index_i = clamp(floor(coord), 0.0, 127.0);
float index_f = coord - index_i; // fract() cannot be used here because 128.0 needs to be
// extracted as index_i = 127.0 and index_f = 1.0
vec2 entry = texelFetch(lut, int(index_i), 0).rg;
return clamp(entry.r + entry.g * index_f, 0.0, 1.0);
}
)";
// Noise utility
if (config.state.proctex.noise_enable) {
// See swrasterizer/proctex.cpp for more information about these functions
out += R"(
int ProcTexNoiseRand1D(int v) {
const int table[] = int[](0,4,10,8,4,9,7,12,5,15,13,14,11,15,2,11);
return ((v % 9 + 2) * 3 & 0xF) ^ table[(v / 9) & 0xF];
}
float ProcTexNoiseRand2D(vec2 point) {
const int table[] = int[](10,2,15,8,0,7,4,5,5,13,2,6,13,9,3,14);
int u2 = ProcTexNoiseRand1D(int(point.x));
int v2 = ProcTexNoiseRand1D(int(point.y));
v2 += ((u2 & 3) == 1) ? 4 : 0;
v2 ^= (u2 & 1) * 6;
v2 += 10 + u2;
v2 &= 0xF;
v2 ^= table[u2];
return -1.0 + float(v2) * 2.0/ 15.0;
}
float ProcTexNoiseCoef(vec2 x) {
vec2 grid = 9.0 * proctex_noise_f * abs(x + proctex_noise_p);
vec2 point = floor(grid);
vec2 frac = grid - point;
float g0 = ProcTexNoiseRand2D(point) * (frac.x + frac.y);
float g1 = ProcTexNoiseRand2D(point + vec2(1.0, 0.0)) * (frac.x + frac.y - 1.0);
float g2 = ProcTexNoiseRand2D(point + vec2(0.0, 1.0)) * (frac.x + frac.y - 1.0);
float g3 = ProcTexNoiseRand2D(point + vec2(1.0, 1.0)) * (frac.x + frac.y - 2.0);
float x_noise = ProcTexLookupLUT(proctex_noise_lut, frac.x);
float y_noise = ProcTexLookupLUT(proctex_noise_lut, frac.y);
float x0 = mix(g0, g1, x_noise);
float x1 = mix(g2, g3, x_noise);
return mix(x0, x1, y_noise);
}
)";
}
out += "vec4 ProcTex() {\n";
out += "vec2 uv = abs(texcoord[" + std::to_string(config.state.proctex.coord) + "]);\n";
// Get shift offset before noise generation
out += "float u_shift = ";
AppendProcTexShiftOffset(out, "uv.y", config.state.proctex.u_shift,
config.state.proctex.u_clamp);
out += ";\n";
out += "float v_shift = ";
AppendProcTexShiftOffset(out, "uv.x", config.state.proctex.v_shift,
config.state.proctex.v_clamp);
out += ";\n";
// Generate noise
if (config.state.proctex.noise_enable) {
out += "uv += proctex_noise_a * ProcTexNoiseCoef(uv);\n";
out += "uv = abs(uv);\n";
}
// Shift
out += "float u = uv.x + u_shift;\n";
out += "float v = uv.y + v_shift;\n";
// Clamp
AppendProcTexClamp(out, "u", config.state.proctex.u_clamp);
AppendProcTexClamp(out, "v", config.state.proctex.v_clamp);
// Combine and map
out += "float lut_coord = ";
AppendProcTexCombineAndMap(out, config.state.proctex.color_combiner, "proctex_color_map");
out += ";\n";
// Look up color
// For the color lut, coord=0.0 is lut[offset] and coord=1.0 is lut[offset+width-1]
out += "lut_coord *= " + std::to_string(config.state.proctex.lut_width - 1) + ";\n";
// TODO(wwylele): implement mipmap
switch (config.state.proctex.lut_filter) {
case ProcTexFilter::Linear:
case ProcTexFilter::LinearMipmapLinear:
case ProcTexFilter::LinearMipmapNearest:
out += "int lut_index_i = int(lut_coord) + " +
std::to_string(config.state.proctex.lut_offset) + ";\n";
out += "float lut_index_f = fract(lut_coord);\n";
out += "vec4 final_color = texelFetch(proctex_lut, lut_index_i, 0) + lut_index_f * "
"texelFetch(proctex_diff_lut, lut_index_i, 0);\n";
break;
case ProcTexFilter::Nearest:
case ProcTexFilter::NearestMipmapLinear:
case ProcTexFilter::NearestMipmapNearest:
out += "lut_coord += " + std::to_string(config.state.proctex.lut_offset) + ";\n";
out += "vec4 final_color = texelFetch(proctex_lut, int(round(lut_coord)), 0);\n";
break;
}
if (config.state.proctex.separate_alpha) {
// Note: in separate alpha mode, the alpha channel skips the color LUT look up stage. It
// uses the output of CombineAndMap directly instead.
out += "float final_alpha = ";
AppendProcTexCombineAndMap(out, config.state.proctex.alpha_combiner, "proctex_alpha_map");
out += ";\n";
out += "return vec4(final_color.xyz, final_alpha);\n}\n";
} else {
out += "return final_color;\n}\n";
}
}
std::string GenerateFragmentShader(const PicaShaderConfig& config) {
const auto& state = config.state;
std::string out = R"(
#version 330 core
#define NUM_TEV_STAGES 6
#define NUM_LIGHTS 8
// Texture coordinate offsets and scales
#define OFFSET_256 (0.5 / 256.0)
#define SCALE_256 (255.0 / 256.0)
in vec4 primary_color;
in vec2 texcoord[3];
in float texcoord0_w;
in vec4 normquat;
in vec3 view;
in vec4 gl_FragCoord;
out vec4 color;
struct LightSrc {
vec3 specular_0;
vec3 specular_1;
vec3 diffuse;
vec3 ambient;
vec3 position;
float dist_atten_bias;
float dist_atten_scale;
};
layout (std140) uniform shader_data {
vec2 framebuffer_scale;
int alphatest_ref;
float depth_scale;
float depth_offset;
int scissor_x1;
int scissor_y1;
int scissor_x2;
int scissor_y2;
vec3 fog_color;
vec2 proctex_noise_f;
vec2 proctex_noise_a;
vec2 proctex_noise_p;
vec3 lighting_global_ambient;
LightSrc light_src[NUM_LIGHTS];
vec4 const_color[NUM_TEV_STAGES];
vec4 tev_combiner_buffer_color;
};
uniform sampler2D tex[3];
uniform sampler1D lut[6];
uniform usampler1D fog_lut;
uniform sampler1D proctex_noise_lut;
uniform sampler1D proctex_color_map;
uniform sampler1D proctex_alpha_map;
uniform sampler1D proctex_lut;
uniform sampler1D proctex_diff_lut;
// Rotate the vector v by the quaternion q
vec3 quaternion_rotate(vec4 q, vec3 v) {
return v + 2.0 * cross(q.xyz, cross(q.xyz, v) + q.w * v);
})";
if (config.state.proctex.enable)
AppendProcTexSampler(out, config);
out += R"(
void main() {
vec4 primary_fragment_color = vec4(0.0);
vec4 secondary_fragment_color = vec4(0.0);
)";
// Do not do any sort of processing if it's obvious we're not going to pass the alpha test
if (state.alpha_test_func == FramebufferRegs::CompareFunc::Never) {
out += "discard; }";
return out;
}
// Append the scissor test
if (state.scissor_test_mode != RasterizerRegs::ScissorMode::Disabled) {
out += "if (";
// Negate the condition if we have to keep only the pixels outside the scissor box
if (state.scissor_test_mode == RasterizerRegs::ScissorMode::Include)
out += "!";
out += "(gl_FragCoord.x >= scissor_x1 && "
"gl_FragCoord.y >= scissor_y1 && "
"gl_FragCoord.x < scissor_x2 && "
"gl_FragCoord.y < scissor_y2)) discard;\n";
}
out += "float z_over_w = 1.0 - gl_FragCoord.z * 2.0;\n";
out += "float depth = z_over_w * depth_scale + depth_offset;\n";
if (state.depthmap_enable == RasterizerRegs::DepthBuffering::WBuffering) {
out += "depth /= gl_FragCoord.w;\n";
}
if (state.lighting.enable)
WriteLighting(out, config);
out += "vec4 combiner_buffer = vec4(0.0);\n";
out += "vec4 next_combiner_buffer = tev_combiner_buffer_color;\n";
out += "vec4 last_tex_env_out = vec4(0.0);\n";
for (size_t index = 0; index < state.tev_stages.size(); ++index)
WriteTevStage(out, config, (unsigned)index);
if (state.alpha_test_func != FramebufferRegs::CompareFunc::Always) {
out += "if (";
AppendAlphaTestCondition(out, state.alpha_test_func);
out += ") discard;\n";
}
// Append fog combiner
if (state.fog_mode == TexturingRegs::FogMode::Fog) {
// Get index into fog LUT
if (state.fog_flip) {
out += "float fog_index = (1.0 - depth) * 128.0;\n";
} else {
out += "float fog_index = depth * 128.0;\n";
}
// Generate clamped fog factor from LUT for given fog index
out += "float fog_i = clamp(floor(fog_index), 0.0, 127.0);\n";
out += "float fog_f = fog_index - fog_i;\n";
out += "uint fog_lut_entry = texelFetch(fog_lut, int(fog_i), 0).r;\n";
out += "float fog_lut_entry_difference = float(int((fog_lut_entry & 0x1FFFU) << 19U) >> "
"19);\n"; // Extract signed difference
out += "float fog_lut_entry_value = float((fog_lut_entry >> 13U) & 0x7FFU);\n";
out += "float fog_factor = (fog_lut_entry_value + fog_lut_entry_difference * fog_f) / "
"2047.0;\n";
out += "fog_factor = clamp(fog_factor, 0.0, 1.0);\n";
// Blend the fog
out += "last_tex_env_out.rgb = mix(fog_color.rgb, last_tex_env_out.rgb, fog_factor);\n";
}
out += "gl_FragDepth = depth;\n";
out += "color = last_tex_env_out;\n";
out += "}";
return out;
}
std::string GenerateVertexShader() {
std::string out = "#version 330 core\n";
out += "layout(location = " + std::to_string((int)ATTRIBUTE_POSITION) +
") in vec4 vert_position;\n";
out += "layout(location = " + std::to_string((int)ATTRIBUTE_COLOR) + ") in vec4 vert_color;\n";
out += "layout(location = " + std::to_string((int)ATTRIBUTE_TEXCOORD0) +
") in vec2 vert_texcoord0;\n";
out += "layout(location = " + std::to_string((int)ATTRIBUTE_TEXCOORD1) +
") in vec2 vert_texcoord1;\n";
out += "layout(location = " + std::to_string((int)ATTRIBUTE_TEXCOORD2) +
") in vec2 vert_texcoord2;\n";
out += "layout(location = " + std::to_string((int)ATTRIBUTE_TEXCOORD0_W) +
") in float vert_texcoord0_w;\n";
out += "layout(location = " + std::to_string((int)ATTRIBUTE_NORMQUAT) +
") in vec4 vert_normquat;\n";
out += "layout(location = " + std::to_string((int)ATTRIBUTE_VIEW) + ") in vec3 vert_view;\n";
out += R"(
out vec4 primary_color;
out vec2 texcoord[3];
out float texcoord0_w;
out vec4 normquat;
out vec3 view;
void main() {
primary_color = vert_color;
texcoord[0] = vert_texcoord0;
texcoord[1] = vert_texcoord1;
texcoord[2] = vert_texcoord2;
texcoord0_w = vert_texcoord0_w;
normquat = vert_normquat;
view = vert_view;
gl_Position = vec4(vert_position.x, vert_position.y, -vert_position.z, vert_position.w);
}
)";
return out;
}
} // namespace GLShader