Method shaderSetup

src/IECoreGL/CurvesPrimitive.cpp:153–214

}

const Shader::Setup *CurvesPrimitive::shaderSetup( const Shader *shader, State *state ) const
{
	bool linear, ribbons;
	renderMode( state, linear, ribbons );

	if( linear && !ribbons  )
	{
		// we just render in the standard way.
		return Primitive::shaderSetup( shader, state );
	}

	// we're rendering with ribbons and/or cubic interpolation. we need
	// to substitute in a geometry shader to do the work.

	for( MemberData::GeometrySetupVector::const_iterator it = m_memberData->geometrySetups.begin(), eIt = m_memberData->geometrySetups.end(); it != eIt; it++ )
	{
		if( it->originalShader == shader && it->linear == linear && it->ribbons == ribbons )
		{
			return it->shaderSetup.get();
		}
	}

	ConstShaderPtr geometryShader = shader;
	ShaderStateComponent *shaderStateComponent = state->get<ShaderStateComponent>();
	if( geometryShader->geometrySource() == "" )
	{
		// if the current shader has a specific geometry shader component,
		// then we assume the user has provided one capable of doing the tesselation,
		// but if not then we substitute in our own geometry shader.
		ShaderLoader *shaderLoader = shaderStateComponent->shaderLoader();
		if( ribbons )
		{
			if( linear )
			{
				geometryShader = shaderLoader->create( geometryShader->vertexSource(), linearRibbonsGeometrySource(), geometryShader->fragmentSource() );
			}
			else
			{
				geometryShader = shaderLoader->create( geometryShader->vertexSource(), cubicRibbonsGeometrySource(), geometryShader->fragmentSource() );
			}
		}
		else
		{
			// When drawing as lines, default to the constant fragment source, because using a facing ratio
			// shader doesn't work
			geometryShader = shaderLoader->create(
				geometryShader->vertexSource(), cubicLinesGeometrySource(),
				geometryShader->fragmentSource() != "" ? geometryShader->fragmentSource() : Shader::constantFragmentSource()
			);
		}
	}

	Shader::SetupPtr geometryShaderSetup = new Shader::Setup( geometryShader );
	shaderStateComponent->addParametersToShaderSetup( geometryShaderSetup.get() );
	addPrimitiveVariablesToShaderSetup( geometryShaderSetup.get() );
	geometryShaderSetup->addUniformParameter( "basis", new IECore::M44fData( m_memberData->basis.matrix ) );
	geometryShaderSetup->addUniformParameter( "width", new IECore::M44fData( m_memberData->width ) );