dolphin/Source/Core/VideoCommon/GeometryShaderGen.cpp

392 lines
14 KiB
C++

// Copyright 2014 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include "VideoCommon/GeometryShaderGen.h"
#include <cmath>
#include "Common/CommonTypes.h"
#include "Common/EnumMap.h"
#include "VideoCommon/DriverDetails.h"
#include "VideoCommon/LightingShaderGen.h"
#include "VideoCommon/VideoCommon.h"
#include "VideoCommon/VideoConfig.h"
#include "VideoCommon/XFMemory.h"
constexpr Common::EnumMap<const char*, PrimitiveType::TriangleStrip> primitives_ogl{
"points",
"lines",
"triangles",
"triangles",
};
constexpr Common::EnumMap<const char*, PrimitiveType::TriangleStrip> primitives_d3d{
"point",
"line",
"triangle",
"triangle",
};
constexpr Common::EnumMap<u32, PrimitiveType::TriangleStrip> vertex_in_map{1u, 2u, 3u, 3u};
constexpr Common::EnumMap<u32, PrimitiveType::TriangleStrip> vertex_out_map{4u, 4u, 4u, 3u};
bool geometry_shader_uid_data::IsPassthrough() const
{
const bool stereo = g_ActiveConfig.stereo_mode != StereoMode::Off;
const bool wireframe = g_ActiveConfig.bWireFrame;
return primitive_type >= static_cast<u32>(PrimitiveType::Triangles) && !stereo && !wireframe;
}
GeometryShaderUid GetGeometryShaderUid(PrimitiveType primitive_type)
{
GeometryShaderUid out;
geometry_shader_uid_data* const uid_data = out.GetUidData();
uid_data->primitive_type = static_cast<u32>(primitive_type);
uid_data->numTexGens = xfmem.numTexGen.numTexGens;
return out;
}
static void EmitVertex(ShaderCode& out, const ShaderHostConfig& host_config,
const geometry_shader_uid_data* uid_data, const char* vertex,
APIType api_type, bool wireframe, bool first_vertex = false);
static void EndPrimitive(ShaderCode& out, const ShaderHostConfig& host_config,
const geometry_shader_uid_data* uid_data, APIType api_type,
bool wireframe);
ShaderCode GenerateGeometryShaderCode(APIType api_type, const ShaderHostConfig& host_config,
const geometry_shader_uid_data* uid_data)
{
ShaderCode out;
// Non-uid template parameters will write to the dummy data (=> gets optimized out)
const bool wireframe = host_config.wireframe;
const bool msaa = host_config.msaa;
const bool ssaa = host_config.ssaa;
const bool stereo = host_config.stereo;
const auto primitive_type = static_cast<PrimitiveType>(uid_data->primitive_type);
const u32 vertex_in = vertex_in_map[primitive_type];
u32 vertex_out = vertex_out_map[primitive_type];
if (wireframe)
vertex_out++;
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
{
// Insert layout parameters
if (host_config.backend_gs_instancing)
{
out.Write("layout({}, invocations = {}) in;\n", primitives_ogl[primitive_type],
stereo ? 2 : 1);
out.Write("layout({}_strip, max_vertices = {}) out;\n", wireframe ? "line" : "triangle",
vertex_out);
}
else
{
out.Write("layout({}) in;\n", primitives_ogl[primitive_type]);
out.Write("layout({}_strip, max_vertices = {}) out;\n", wireframe ? "line" : "triangle",
stereo ? vertex_out * 2 : vertex_out);
}
}
out.Write("{}", s_lighting_struct);
// uniforms
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
out.Write("UBO_BINDING(std140, 3) uniform GSBlock {{\n");
else
out.Write("cbuffer GSBlock {{\n");
out.Write("\tfloat4 " I_STEREOPARAMS ";\n"
"\tfloat4 " I_LINEPTPARAMS ";\n"
"\tint4 " I_TEXOFFSET ";\n"
"}};\n");
out.Write("struct VS_OUTPUT {{\n");
GenerateVSOutputMembers(out, api_type, uid_data->numTexGens, host_config, "");
out.Write("}};\n");
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
{
if (host_config.backend_gs_instancing)
out.Write("#define InstanceID gl_InvocationID\n");
out.Write("VARYING_LOCATION(0) in VertexData {{\n");
GenerateVSOutputMembers(out, api_type, uid_data->numTexGens, host_config,
GetInterpolationQualifier(msaa, ssaa, true, true));
out.Write("}} vs[{}];\n", vertex_in);
out.Write("VARYING_LOCATION(0) out VertexData {{\n");
GenerateVSOutputMembers(out, api_type, uid_data->numTexGens, host_config,
GetInterpolationQualifier(msaa, ssaa, true, false));
if (stereo)
out.Write("\tflat int layer;\n");
out.Write("}} ps;\n");
out.Write("void main()\n{{\n");
}
else // D3D
{
out.Write("struct VertexData {{\n");
out.Write("\tVS_OUTPUT o;\n");
if (stereo)
out.Write("\tuint layer : SV_RenderTargetArrayIndex;\n");
out.Write("}};\n");
if (host_config.backend_gs_instancing)
{
out.Write("[maxvertexcount({})]\n[instance({})]\n", vertex_out, stereo ? 2 : 1);
out.Write("void main({} VS_OUTPUT o[{}], inout {}Stream<VertexData> output, in uint "
"InstanceID : SV_GSInstanceID)\n{{\n",
primitives_d3d[primitive_type], vertex_in, wireframe ? "Line" : "Triangle");
}
else
{
out.Write("[maxvertexcount({})]\n", stereo ? vertex_out * 2 : vertex_out);
out.Write("void main({} VS_OUTPUT o[{}], inout {}Stream<VertexData> output)\n{{\n",
primitives_d3d[primitive_type], vertex_in, wireframe ? "Line" : "Triangle");
}
out.Write("\tVertexData ps;\n");
}
if (primitive_type == PrimitiveType::Lines)
{
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
{
out.Write("\tVS_OUTPUT start, end;\n");
AssignVSOutputMembers(out, "start", "vs[0]", uid_data->numTexGens, host_config);
AssignVSOutputMembers(out, "end", "vs[1]", uid_data->numTexGens, host_config);
}
else
{
out.Write("\tVS_OUTPUT start = o[0];\n"
"\tVS_OUTPUT end = o[1];\n");
}
// GameCube/Wii's line drawing algorithm is a little quirky. It does not
// use the correct line caps. Instead, the line caps are vertical or
// horizontal depending the slope of the line.
out.Write("\tfloat2 offset;\n"
"\tfloat2 to = abs(end.pos.xy / end.pos.w - start.pos.xy / start.pos.w);\n"
// FIXME: What does real hardware do when line is at a 45-degree angle?
// FIXME: Lines aren't drawn at the correct width. See Twilight Princess map.
"\tif (" I_LINEPTPARAMS ".y * to.y > " I_LINEPTPARAMS ".x * to.x) {{\n"
// Line is more tall. Extend geometry left and right.
// Lerp LineWidth/2 from [0..VpWidth] to [-1..1]
"\t\toffset = float2(" I_LINEPTPARAMS ".z / " I_LINEPTPARAMS ".x, 0);\n"
"\t}} else {{\n"
// Line is more wide. Extend geometry up and down.
// Lerp LineWidth/2 from [0..VpHeight] to [1..-1]
"\t\toffset = float2(0, -" I_LINEPTPARAMS ".z / " I_LINEPTPARAMS ".y);\n"
"\t}}\n");
}
else if (primitive_type == PrimitiveType::Points)
{
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
{
out.Write("\tVS_OUTPUT center;\n");
AssignVSOutputMembers(out, "center", "vs[0]", uid_data->numTexGens, host_config);
}
else
{
out.Write("\tVS_OUTPUT center = o[0];\n");
}
// Offset from center to upper right vertex
// Lerp PointSize/2 from [0,0..VpWidth,VpHeight] to [-1,1..1,-1]
out.Write("\tfloat2 offset = float2(" I_LINEPTPARAMS ".w / " I_LINEPTPARAMS
".x, -" I_LINEPTPARAMS ".w / " I_LINEPTPARAMS ".y) * center.pos.w;\n");
}
if (stereo)
{
// If the GPU supports invocation we don't need a for loop and can simply use the
// invocation identifier to determine which layer we're rendering.
if (host_config.backend_gs_instancing)
out.Write("\tint eye = InstanceID;\n");
else
out.Write("\tfor (int eye = 0; eye < 2; ++eye) {{\n");
}
if (wireframe)
out.Write("\tVS_OUTPUT first;\n");
out.Write("\tfor (int i = 0; i < {}; ++i) {{\n", vertex_in);
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
{
out.Write("\tVS_OUTPUT f;\n");
AssignVSOutputMembers(out, "f", "vs[i]", uid_data->numTexGens, host_config);
if (host_config.backend_depth_clamp &&
DriverDetails::HasBug(DriverDetails::BUG_BROKEN_CLIP_DISTANCE))
{
// On certain GPUs we have to consume the clip distance from the vertex shader
// or else the other vertex shader outputs will get corrupted.
out.Write("\tf.clipDist0 = gl_in[i].gl_ClipDistance[0];\n"
"\tf.clipDist1 = gl_in[i].gl_ClipDistance[1];\n");
}
}
else
{
out.Write("\tVS_OUTPUT f = o[i];\n");
}
if (stereo)
{
// Select the output layer
out.Write("\tps.layer = eye;\n");
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
out.Write("\tgl_Layer = eye;\n");
// For stereoscopy add a small horizontal offset in Normalized Device Coordinates proportional
// to the depth of the vertex. We retrieve the depth value from the w-component of the projected
// vertex which contains the negated z-component of the original vertex.
// For negative parallax (out-of-screen effects) we subtract a convergence value from
// the depth value. This results in objects at a distance smaller than the convergence
// distance to seemingly appear in front of the screen.
// This formula is based on page 13 of the "Nvidia 3D Vision Automatic, Best Practices Guide"
out.Write("\tfloat hoffset = (eye == 0) ? " I_STEREOPARAMS ".x : " I_STEREOPARAMS ".y;\n");
out.Write("\tf.pos.x += hoffset * (f.pos.w - " I_STEREOPARAMS ".z);\n");
}
if (primitive_type == PrimitiveType::Lines)
{
out.Write("\tVS_OUTPUT l = f;\n"
"\tVS_OUTPUT r = f;\n");
out.Write("\tl.pos.xy -= offset * l.pos.w;\n"
"\tr.pos.xy += offset * r.pos.w;\n");
out.Write("\tif (" I_TEXOFFSET "[2] != 0) {{\n");
out.Write("\tfloat texOffset = 1.0 / float(" I_TEXOFFSET "[2]);\n");
for (u32 i = 0; i < uid_data->numTexGens; ++i)
{
out.Write("\tif (((" I_TEXOFFSET "[0] >> {}) & 0x1) != 0)\n", i);
out.Write("\t\tr.tex{}.x += texOffset;\n", i);
}
out.Write("\t}}\n");
EmitVertex(out, host_config, uid_data, "l", api_type, wireframe, true);
EmitVertex(out, host_config, uid_data, "r", api_type, wireframe);
}
else if (primitive_type == PrimitiveType::Points)
{
out.Write("\tVS_OUTPUT ll = f;\n"
"\tVS_OUTPUT lr = f;\n"
"\tVS_OUTPUT ul = f;\n"
"\tVS_OUTPUT ur = f;\n");
out.Write("\tll.pos.xy += float2(-1,-1) * offset;\n"
"\tlr.pos.xy += float2(1,-1) * offset;\n"
"\tul.pos.xy += float2(-1,1) * offset;\n"
"\tur.pos.xy += offset;\n");
out.Write("\tif (" I_TEXOFFSET "[3] != 0) {{\n");
out.Write("\tfloat2 texOffset = float2(1.0 / float(" I_TEXOFFSET
"[3]), 1.0 / float(" I_TEXOFFSET "[3]));\n");
for (u32 i = 0; i < uid_data->numTexGens; ++i)
{
out.Write("\tif (((" I_TEXOFFSET "[1] >> {}) & 0x1) != 0) {{\n", i);
out.Write("\t\tul.tex{}.xy += float2(0,1) * texOffset;\n", i);
out.Write("\t\tur.tex{}.xy += texOffset;\n", i);
out.Write("\t\tlr.tex{}.xy += float2(1,0) * texOffset;\n", i);
out.Write("\t}}\n");
}
out.Write("\t}}\n");
EmitVertex(out, host_config, uid_data, "ll", api_type, wireframe, true);
EmitVertex(out, host_config, uid_data, "lr", api_type, wireframe);
EmitVertex(out, host_config, uid_data, "ul", api_type, wireframe);
EmitVertex(out, host_config, uid_data, "ur", api_type, wireframe);
}
else
{
EmitVertex(out, host_config, uid_data, "f", api_type, wireframe, true);
}
out.Write("\t}}\n");
EndPrimitive(out, host_config, uid_data, api_type, wireframe);
if (stereo && !host_config.backend_gs_instancing)
out.Write("\t}}\n");
out.Write("}}\n");
return out;
}
static void EmitVertex(ShaderCode& out, const ShaderHostConfig& host_config,
const geometry_shader_uid_data* uid_data, const char* vertex,
APIType api_type, bool wireframe, bool first_vertex)
{
if (wireframe && first_vertex)
out.Write("\tif (i == 0) first = {};\n", vertex);
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
{
// Vulkan NDC space has Y pointing down (right-handed NDC space).
if (api_type == APIType::Vulkan)
out.Write("\tgl_Position = float4({0}.pos.x, -{0}.pos.y, {0}.pos.z, {0}.pos.w);\n", vertex);
else
out.Write("\tgl_Position = {}.pos;\n", vertex);
if (host_config.backend_depth_clamp)
{
out.Write("\tgl_ClipDistance[0] = {}.clipDist0;\n", vertex);
out.Write("\tgl_ClipDistance[1] = {}.clipDist1;\n", vertex);
}
AssignVSOutputMembers(out, "ps", vertex, uid_data->numTexGens, host_config);
}
else
{
out.Write("\tps.o = {};\n", vertex);
}
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
out.Write("\tEmitVertex();\n");
else
out.Write("\toutput.Append(ps);\n");
}
static void EndPrimitive(ShaderCode& out, const ShaderHostConfig& host_config,
const geometry_shader_uid_data* uid_data, APIType api_type, bool wireframe)
{
if (wireframe)
EmitVertex(out, host_config, uid_data, "first", api_type, wireframe);
if (api_type == APIType::OpenGL || api_type == APIType::Vulkan)
out.Write("\tEndPrimitive();\n");
else
out.Write("\toutput.RestartStrip();\n");
}
void EnumerateGeometryShaderUids(const std::function<void(const GeometryShaderUid&)>& callback)
{
GeometryShaderUid uid;
const std::array<PrimitiveType, 3> primitive_lut = {
{g_ActiveConfig.backend_info.bSupportsPrimitiveRestart ? PrimitiveType::TriangleStrip :
PrimitiveType::Triangles,
PrimitiveType::Lines, PrimitiveType::Points}};
for (PrimitiveType primitive : primitive_lut)
{
geometry_shader_uid_data* const guid = uid.GetUidData();
guid->primitive_type = static_cast<u32>(primitive);
for (u32 texgens = 0; texgens <= 8; texgens++)
{
guid->numTexGens = texgens;
callback(uid);
}
}
}