dolphin/Source/Core/VideoCommon/GeometryShaderGen.cpp

135 lines
4.4 KiB
C++

// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.
#include <cmath>
#include <locale.h>
#ifdef __APPLE__
#include <xlocale.h>
#endif
#include "VideoCommon/GeometryShaderGen.h"
#include "VideoCommon/LightingShaderGen.h"
#include "VideoCommon/VertexShaderGen.h"
#include "VideoCommon/VideoConfig.h"
static char text[16384];
template<class T>
static inline void GenerateGeometryShader(T& out, u32 components, API_TYPE ApiType)
{
// Non-uid template parameters will write to the dummy data (=> gets optimized out)
geometry_shader_uid_data dummy_data;
geometry_shader_uid_data* uid_data = out.template GetUidData<geometry_shader_uid_data>();
if (uid_data == nullptr)
uid_data = &dummy_data;
out.SetBuffer(text);
const bool is_writing_shadercode = (out.GetBuffer() != nullptr);
#ifndef ANDROID
locale_t locale;
locale_t old_locale;
if (is_writing_shadercode)
{
locale = newlocale(LC_NUMERIC_MASK, "C", nullptr); // New locale for compilation
old_locale = uselocale(locale); // Apply the locale for this thread
}
#endif
if (is_writing_shadercode)
text[sizeof(text) - 1] = 0x7C; // canary
out.Write("//Geometry Shader for 3D stereoscopy\n");
uid_data->stereo = g_ActiveConfig.iStereoMode > 0;
if (ApiType == API_OPENGL)
{
// Insert layout parameters
if (g_ActiveConfig.backend_info.bSupportsGSInstancing)
out.Write("layout(triangles, invocations = %d) in;\n", g_ActiveConfig.iStereoMode > 0 ? 2 : 1);
else
out.Write("layout(triangles) in;\n");
out.Write("layout(triangle_strip, max_vertices = %d) out;\n", g_ActiveConfig.backend_info.bSupportsGSInstancing ? 3 : 6);
}
out.Write("%s", s_lighting_struct);
// uniforms
if (ApiType == API_OPENGL)
out.Write("layout(std140%s) uniform VSBlock {\n", g_ActiveConfig.backend_info.bSupportsBindingLayout ? ", binding = 2" : "");
else
out.Write("cbuffer VSBlock {\n");
out.Write(s_shader_uniforms);
out.Write("};\n");
uid_data->numTexGens = xfmem.numTexGen.numTexGens;
uid_data->pixel_lighting = g_ActiveConfig.bEnablePixelLighting;
GenerateVSOutputStruct(out, ApiType);
out.Write("centroid in VS_OUTPUT o[3];\n");
out.Write("centroid out VS_OUTPUT f;\n");
out.Write("flat out int layer;\n");
out.Write("void main()\n{\n");
// 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 (g_ActiveConfig.backend_info.bSupportsGSInstancing)
out.Write("\tint l = gl_InvocationID;\n");
else
out.Write("\tfor (int l = 0; l < %d; ++l) {\n", g_ActiveConfig.iStereoMode > 0 ? 2 : 1);
out.Write("\tfor (int i = 0; i < 3; ++i) {\n");
out.Write("\t\tlayer = l;\n");
out.Write("\t\tgl_Layer = l;\n");
out.Write("\t\tf = o[i];\n");
out.Write("\t\tfloat4 pos = o[i].pos;\n");
if (g_ActiveConfig.iStereoMode > 0)
{
// 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("\t\tf.clipPos.x = o[i].clipPos.x + " I_STEREOPARAMS"[l] * (o[i].clipPos.w - " I_STEREOPARAMS"[2]);\n");
out.Write("\t\tpos.x = o[i].pos.x + " I_STEREOPARAMS"[l] * (o[i].pos.w - " I_STEREOPARAMS"[2]);\n");
}
out.Write("\t\tf.pos.x = pos.x;\n");
out.Write("\t\tgl_Position = pos;\n");
out.Write("\t\tEmitVertex();\n");
out.Write("\t}\n");
out.Write("\tEndPrimitive();\n");
if (!g_ActiveConfig.backend_info.bSupportsGSInstancing)
out.Write("\t}\n");
out.Write("}\n");
if (is_writing_shadercode)
{
if (text[sizeof(text) - 1] != 0x7C)
PanicAlert("GeometryShader generator - buffer too small, canary has been eaten!");
#ifndef ANDROID
uselocale(old_locale); // restore locale
freelocale(locale);
#endif
}
}
void GetGeometryShaderUid(GeometryShaderUid& object, u32 components, API_TYPE ApiType)
{
GenerateGeometryShader<GeometryShaderUid>(object, components, ApiType);
}
void GenerateGeometryShaderCode(ShaderCode& object, u32 components, API_TYPE ApiType)
{
GenerateGeometryShader<ShaderCode>(object, components, ApiType);
}