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UnrealEngine/Engine/Source/ThirdParty/MaterialX/MaterialX-1.38.10/source/MaterialXGenShader/Nodes/HwBitangentNode.cpp
2025-05-18 13:04:45 +08:00

136 lines
5.2 KiB
C++

//
// Copyright Contributors to the MaterialX Project
// SPDX-License-Identifier: Apache-2.0
//
#include <MaterialXGenShader/Nodes/HwBitangentNode.h>
#include <MaterialXGenShader/Shader.h>
MATERIALX_NAMESPACE_BEGIN
ShaderNodeImplPtr HwBitangentNode::create()
{
return std::make_shared<HwBitangentNode>();
}
void HwBitangentNode::createVariables(const ShaderNode& node, GenContext& context, Shader& shader) const
{
const GenOptions& options = context.getOptions();
ShaderStage& vs = shader.getStage(Stage::VERTEX);
ShaderStage& ps = shader.getStage(Stage::PIXEL);
if (options.hwImplicitBitangents)
{
addStageInput(HW::VERTEX_INPUTS, Type::VECTOR3, HW::T_IN_NORMAL, vs);
addStageInput(HW::VERTEX_INPUTS, Type::VECTOR3, HW::T_IN_TANGENT, vs);
}
else
{
addStageInput(HW::VERTEX_INPUTS, Type::VECTOR3, HW::T_IN_BITANGENT, vs);
}
const ShaderInput* spaceInput = node.getInput(SPACE);
const int space = spaceInput ? spaceInput->getValue()->asA<int>() : OBJECT_SPACE;
if (space == WORLD_SPACE)
{
addStageConnector(HW::VERTEX_DATA, Type::VECTOR3, HW::T_BITANGENT_WORLD, vs, ps);
addStageUniform(HW::PRIVATE_UNIFORMS, Type::MATRIX44, HW::T_WORLD_MATRIX, vs);
if (options.hwImplicitBitangents)
{
addStageConnector(HW::VERTEX_DATA, Type::VECTOR3, HW::T_NORMAL_WORLD, vs, ps);
addStageConnector(HW::VERTEX_DATA, Type::VECTOR3, HW::T_TANGENT_WORLD, vs, ps);
addStageUniform(HW::PRIVATE_UNIFORMS, Type::MATRIX44, HW::T_WORLD_INVERSE_TRANSPOSE_MATRIX, vs);
}
}
else
{
addStageConnector(HW::VERTEX_DATA, Type::VECTOR3, HW::T_BITANGENT_OBJECT, vs, ps);
}
}
void HwBitangentNode::emitFunctionCall(const ShaderNode& node, GenContext& context, ShaderStage& stage) const
{
const HwShaderGenerator& shadergen = static_cast<const HwShaderGenerator&>(context.getShaderGenerator());
const GenOptions& options = context.getOptions();
const ShaderInput* spaceInput = node.getInput(SPACE);
const int space = spaceInput ? spaceInput->getValue()->asA<int>() : OBJECT_SPACE;
DEFINE_SHADER_STAGE(stage, Stage::VERTEX)
{
VariableBlock& vertexData = stage.getOutputBlock(HW::VERTEX_DATA);
const string prefix = shadergen.getVertexDataPrefix(vertexData);
if (space == WORLD_SPACE)
{
ShaderPort* bitangent = vertexData[HW::T_BITANGENT_WORLD];
if (!bitangent->isEmitted())
{
bitangent->setEmitted();
if (options.hwImplicitBitangents)
{
ShaderPort* normal = vertexData[HW::T_NORMAL_WORLD];
if (!normal->isEmitted())
{
normal->setEmitted();
shadergen.emitLine(prefix + normal->getVariable() + " = normalize((" + HW::T_WORLD_INVERSE_TRANSPOSE_MATRIX + " * vec4(" + HW::T_IN_NORMAL + ", 0.0)).xyz)", stage);
}
ShaderPort* tangent = vertexData[HW::T_TANGENT_WORLD];
if (!tangent->isEmitted())
{
tangent->setEmitted();
shadergen.emitLine(prefix + tangent->getVariable() + " = normalize((" + HW::T_WORLD_MATRIX + " * vec4(" + HW::T_IN_TANGENT + ", 0.0)).xyz)", stage);
}
shadergen.emitLine(prefix + bitangent->getVariable() + " = cross(" + prefix + normal->getVariable() + ", " + prefix + tangent->getVariable() + ")", stage);
}
else
{
shadergen.emitLine(prefix + bitangent->getVariable() + " = normalize((" + HW::T_WORLD_MATRIX + " * vec4(" + HW::T_IN_BITANGENT + ", 0.0)).xyz)", stage);
}
}
}
else
{
ShaderPort* bitangent = vertexData[HW::T_BITANGENT_OBJECT];
if (!bitangent->isEmitted())
{
bitangent->setEmitted();
if (options.hwImplicitBitangents)
{
shadergen.emitLine(prefix + bitangent->getVariable() + " = cross(" + HW::T_IN_NORMAL + ", " + HW::T_IN_TANGENT + ")", stage);
}
else
{
shadergen.emitLine(prefix + bitangent->getVariable() + " = " + HW::T_IN_BITANGENT, stage);
}
}
}
}
DEFINE_SHADER_STAGE(stage, Stage::PIXEL)
{
VariableBlock& vertexData = stage.getInputBlock(HW::VERTEX_DATA);
const string prefix = shadergen.getVertexDataPrefix(vertexData);
shadergen.emitLineBegin(stage);
shadergen.emitOutput(node.getOutput(), true, false, context, stage);
if (space == WORLD_SPACE)
{
const ShaderPort* bitangent = vertexData[HW::T_BITANGENT_WORLD];
shadergen.emitString(" = normalize(" + prefix + bitangent->getVariable() + ")", stage);
}
else
{
const ShaderPort* bitangent = vertexData[HW::T_BITANGENT_OBJECT];
shadergen.emitString(" = normalize(" + prefix + bitangent->getVariable() + ")", stage);
}
shadergen.emitLineEnd(stage);
}
}
MATERIALX_NAMESPACE_END