framework/opengl/gluVarTypeUtil.hpp - third_party/vulkan-cts - Git at Google

 #ifndef _GLUVARTYPEUTIL_HPP
 #define _GLUVARTYPEUTIL_HPP
 /*-------------------------------------------------------------------------
  * drawElements Quality Program OpenGL ES Utilities
  * ------------------------------------------------
  *
  * Copyright 2014 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  *//*!
  * \file
  * \brief Shader variable type utilities.
  *//*--------------------------------------------------------------------*/

 #include "tcuDefs.hpp"
 #include "gluVarType.hpp"

 #include <vector>
 #include <string>
 #include <iterator>

 namespace glu
 {

 // Variable path tokenizer

 class VarTokenizer
 {
 public:
 	enum Token
 	{
 		TOKEN_IDENTIFIER = 0,
 		TOKEN_LEFT_BRACKET,
 		TOKEN_RIGHT_BRACKET,
 		TOKEN_PERIOD,
 		TOKEN_NUMBER,
 		TOKEN_END,

 		TOKEN_LAST
 	};

 					VarTokenizer					(const char* str);
 					~VarTokenizer					(void) {}

 	Token			getToken						(void) const { return m_token;															}
 	std::string		getIdentifier					(void) const { return std::string(m_str+m_tokenStart, m_str+m_tokenStart+m_tokenLen);	}
 	int				getNumber						(void) const;
 	int				getCurrentTokenStartLocation	(void) const { return m_tokenStart;														}
 	int				getCurrentTokenEndLocation		(void) const { return m_tokenStart + m_tokenLen;										}
 	void			advance							(void);

 private:
 	const char*		m_str;

 	Token			m_token;
 	int				m_tokenStart;
 	int				m_tokenLen;
 };

 // VarType subtype path utilities.

 struct VarTypeComponent
 {
 	enum Type
 	{
 		STRUCT_MEMBER = 0,
 		ARRAY_ELEMENT,
 		MATRIX_COLUMN,
 		VECTOR_COMPONENT,

 		VTCTYPE_LAST
 	};

 				VarTypeComponent	(Type type_, int index_)	: type(type_), index(index_) {}
 				VarTypeComponent	(void)						: type(VTCTYPE_LAST), index(0) {}

 	bool		operator==			(const VarTypeComponent& other) const { return type == other.type && index == other.index; }
 	bool		operator!=			(const VarTypeComponent& other) const { return type != other.type || index != other.index; }

 	Type		type;
 	int			index;
 };

 typedef std::vector<VarTypeComponent> TypeComponentVector;

 // TypeComponentVector utilties.

 template <typename Iterator>
 bool			isValidTypePath		(const VarType& type, Iterator begin, Iterator end);

 template <typename Iterator>
 VarType			getVarType			(const VarType& type, Iterator begin, Iterator end);

 inline bool		isValidTypePath		(const VarType& type, const TypeComponentVector& path) { return isValidTypePath(type, path.begin(), path.end()); }
 inline VarType	getVarType			(const VarType& type, const TypeComponentVector& path) { return getVarType(type, path.begin(), path.end()); }

 std::string		parseVariableName	(const char* nameWithPath);
 void			parseTypePath		(const char* nameWithPath, const VarType& type, TypeComponentVector& path);

 // Type path formatter.

 struct TypeAccessFormat
 {
 	TypeAccessFormat (const VarType& type_, const TypeComponentVector& path_) : type(type_), path(path_) {}

 	const VarType&					type;
 	const TypeComponentVector&		path;
 };

 std::ostream&		operator<<		(std::ostream& str, const TypeAccessFormat& format);

 // Subtype path builder.

 class SubTypeAccess
 {
 public:
 								SubTypeAccess		(const VarType& type);

 	SubTypeAccess&				member				(int ndx)	{ m_path.push_back(VarTypeComponent(VarTypeComponent::STRUCT_MEMBER,	ndx)); DE_ASSERT(isValid()); return *this; } //!< Access struct element.
 	SubTypeAccess&				element				(int ndx)	{ m_path.push_back(VarTypeComponent(VarTypeComponent::ARRAY_ELEMENT,	ndx)); DE_ASSERT(isValid()); return *this; } //!< Access array element.
 	SubTypeAccess&				column				(int ndx)	{ m_path.push_back(VarTypeComponent(VarTypeComponent::MATRIX_COLUMN,	ndx)); DE_ASSERT(isValid()); return *this; } //!< Access column.
 	SubTypeAccess&				component			(int ndx)	{ m_path.push_back(VarTypeComponent(VarTypeComponent::VECTOR_COMPONENT,	ndx)); DE_ASSERT(isValid()); return *this; } //!< Access component.
 	SubTypeAccess&				parent				(void)		{ DE_ASSERT(!m_path.empty()); m_path.pop_back(); return *this; }

 	SubTypeAccess				member				(int ndx) const { return SubTypeAccess(*this).member(ndx);		}
 	SubTypeAccess				element				(int ndx) const { return SubTypeAccess(*this).element(ndx);		}
 	SubTypeAccess				column				(int ndx) const { return SubTypeAccess(*this).column(ndx);		}
 	SubTypeAccess				component			(int ndx) const { return SubTypeAccess(*this).component(ndx);	}
 	SubTypeAccess				parent				(void) const	{ return SubTypeAccess(*this).parent();			}

 	bool						isValid				(void) const	{ return isValidTypePath(m_type, m_path);		}
 	VarType						getType				(void) const	{ return getVarType(m_type, m_path);			}
 	const TypeComponentVector&	getPath				(void) const	{ return m_path;								}

 	bool						empty				(void) const { return m_path.empty(); }

 	bool						operator==			(const SubTypeAccess& other) const { return m_path == other.m_path && m_type == other.m_type; }
 	bool						operator!=			(const SubTypeAccess& other) const { return m_path != other.m_path || m_type != other.m_type; }

 private:
 	VarType						m_type;
 	TypeComponentVector			m_path;
 };

 // Subtype iterator.

 // \note VarType must be live during iterator usage.
 template <class IsExpanded>
 class SubTypeIterator : public std::iterator<std::forward_iterator_tag, VarType>
 {
 public:
 	static SubTypeIterator<IsExpanded>	begin				(const VarType* type) { return SubTypeIterator(type);						}
 	static SubTypeIterator<IsExpanded>	end					(const VarType* type) { DE_UNREF(type); return SubTypeIterator(DE_NULL);	}

 	bool								operator==			(const SubTypeIterator<IsExpanded>& other) const { return m_type == other.m_type && m_path == other.m_path; }
 	bool								operator!=			(const SubTypeIterator<IsExpanded>& other) const { return m_type != other.m_type || m_path != other.m_path; }

 	SubTypeIterator<IsExpanded>&		operator++			(void);
 	SubTypeIterator<IsExpanded>			operator++			(int)	{ SubTypeIterator<IsExpanded> copy(*this); ++(*this); return copy; }

 	void								toStream			(std::ostream& str) const { str << TypeAccessFormat(*m_type, m_path); }
 	VarType								getType				(void) const { return getVarType(*m_type, m_path.begin(), m_path.end()); }
 	const TypeComponentVector&			getPath				(void) const { return m_path; }

 	VarType								operator*			(void) const { return getType(); }

 private:
 										SubTypeIterator		(const VarType* type);

 	void								removeTraversed		(void);
 	void								findNext			(void);

 	const VarType*						m_type;
 	TypeComponentVector					m_path;
 };

 struct IsBasicType			{ bool operator() (const VarType& type) const { return type.isBasicType(); } };
 struct IsScalarType			{ bool operator() (const VarType& type) const { return type.isBasicType() && isDataTypeScalar(type.getBasicType()); } };
 struct IsVectorOrScalarType	{ bool operator() (const VarType& type) const { return type.isBasicType() && isDataTypeScalarOrVector(type.getBasicType()); } };

 typedef SubTypeIterator<IsBasicType>			BasicTypeIterator;
 typedef SubTypeIterator<IsVectorOrScalarType>	VectorTypeIterator;
 typedef SubTypeIterator<IsScalarType>			ScalarTypeIterator;

 template <class IsExpanded>
 std::ostream& operator<< (std::ostream& str, const SubTypeIterator<IsExpanded>& iter)
 {
 	iter.toStream(str);
 	return str;
 }

 template <class IsExpanded>
 SubTypeIterator<IsExpanded>::SubTypeIterator (const VarType* type)
 	: m_type(type)
 {
 	if (m_type)
 		findNext();
 }

 template <class IsExpanded>
 SubTypeIterator<IsExpanded>& SubTypeIterator<IsExpanded>::operator++ (void)
 {
 	if (!m_path.empty())
 	{
 		// Remove traversed nodes.
 		removeTraversed();

 		if (!m_path.empty())
 			findNext();
 		else
 			m_type = DE_NULL; // Unset type to signal end.
 	}
 	else
 	{
 		// First type was already expanded.
 		DE_ASSERT(IsExpanded()(getVarType(*m_type, m_path)));
 		m_type = DE_NULL;
 	}

 	return *this;
 }

 template <class IsExpanded>
 void SubTypeIterator<IsExpanded>::removeTraversed (void)
 {
 	DE_ASSERT(m_type && !m_path.empty());

 	// Pop traversed nodes.
 	while (!m_path.empty())
 	{
 		VarTypeComponent&	curComp		= m_path.back();
 		VarType				parentType	= getVarType(*m_type, m_path.begin(), m_path.end()-1);

 		if (curComp.type == VarTypeComponent::MATRIX_COLUMN)
 		{
 			DE_ASSERT(isDataTypeMatrix(parentType.getBasicType()));
 			if (curComp.index+1 < getDataTypeMatrixNumColumns(parentType.getBasicType()))
 				break;
 		}
 		else if (curComp.type == VarTypeComponent::VECTOR_COMPONENT)
 		{
 			DE_ASSERT(isDataTypeVector(parentType.getBasicType()));
 			if (curComp.index+1 < getDataTypeScalarSize(parentType.getBasicType()))
 				break;
 		}
 		else if (curComp.type == VarTypeComponent::ARRAY_ELEMENT)
 		{
 			DE_ASSERT(parentType.isArrayType());
 			if (curComp.index+1 < parentType.getArraySize())
 				break;
 		}
 		else if (curComp.type == VarTypeComponent::STRUCT_MEMBER)
 		{
 			DE_ASSERT(parentType.isStructType());
 			if (curComp.index+1 < parentType.getStructPtr()->getNumMembers())
 				break;
 		}

 		m_path.pop_back();
 	}
 }

 template <class IsExpanded>
 void SubTypeIterator<IsExpanded>::findNext (void)
 {
 	if (!m_path.empty())
 	{
 		// Increment child counter in current level.
 		VarTypeComponent& curComp = m_path.back();
 		curComp.index += 1;
 	}

 	for (;;)
 	{
 		VarType curType = getVarType(*m_type, m_path);

 		if (IsExpanded()(curType))
 			break;

 		// Recurse into child type.
 		if (curType.isBasicType())
 		{
 			DataType basicType = curType.getBasicType();

 			if (isDataTypeMatrix(basicType))
 				m_path.push_back(VarTypeComponent(VarTypeComponent::MATRIX_COLUMN, 0));
 			else if (isDataTypeVector(basicType))
 				m_path.push_back(VarTypeComponent(VarTypeComponent::VECTOR_COMPONENT, 0));
 			else
 				DE_ASSERT(false); // Can't expand scalars - IsExpanded() is buggy.
 		}
 		else if (curType.isArrayType())
 			m_path.push_back(VarTypeComponent(VarTypeComponent::ARRAY_ELEMENT, 0));
 		else if (curType.isStructType())
 			m_path.push_back(VarTypeComponent(VarTypeComponent::STRUCT_MEMBER, 0));
 		else
 			DE_ASSERT(false);
 	}
 }

 template <typename Iterator>
 bool isValidTypePath (const VarType& type, Iterator begin, Iterator end)
 {
 	const VarType*	curType		= &type;
 	Iterator		pathIter	= begin;

 	// Process struct member and array element parts of path.
 	while (pathIter != end)
 	{
 		if (pathIter->type == VarTypeComponent::STRUCT_MEMBER)
 		{
 			if (!curType->isStructType() || !de::inBounds(pathIter->index, 0, curType->getStructPtr()->getNumMembers()))
 				return false;

 			curType = &curType->getStructPtr()->getMember(pathIter->index).getType();
 		}
 		else if (pathIter->type == VarTypeComponent::ARRAY_ELEMENT)
 		{
 			if (!curType->isArrayType() || (curType->getArraySize() != VarType::UNSIZED_ARRAY && !de::inBounds(pathIter->index, 0, curType->getArraySize())))
 				return false;

 			curType = &curType->getElementType();
 		}
 		else
 			break;

 		++pathIter;
 	}

 	if (pathIter != end)
 	{
 		DE_ASSERT(pathIter->type == VarTypeComponent::MATRIX_COLUMN || pathIter->type == VarTypeComponent::VECTOR_COMPONENT);

 		// Current type should be basic type.
 		if (!curType->isBasicType())
 			return false;

 		DataType basicType = curType->getBasicType();

 		if (pathIter->type == VarTypeComponent::MATRIX_COLUMN)
 		{
 			if (!isDataTypeMatrix(basicType))
 				return false;

 			basicType = getDataTypeFloatVec(getDataTypeMatrixNumRows(basicType));
 			++pathIter;
 		}

 		if (pathIter != end && pathIter->type == VarTypeComponent::VECTOR_COMPONENT)
 		{
 			if (!isDataTypeVector(basicType))
 				return false;

 			basicType = getDataTypeScalarType(basicType);
 			++pathIter;
 		}
 	}

 	return pathIter == end;
 }

 template <typename Iterator>
 VarType getVarType (const VarType& type, Iterator begin, Iterator end)
 {
 	TCU_CHECK(isValidTypePath(type, begin, end));

 	const VarType*	curType		= &type;
 	Iterator		pathIter	= begin;

 	// Process struct member and array element parts of path.
 	while (pathIter != end)
 	{
 		if (pathIter->type == VarTypeComponent::STRUCT_MEMBER)
 			curType = &curType->getStructPtr()->getMember(pathIter->index).getType();
 		else if (pathIter->type == VarTypeComponent::ARRAY_ELEMENT)
 			curType = &curType->getElementType();
 		else
 			break;

 		++pathIter;
 	}

 	if (pathIter != end)
 	{
 		DataType	basicType	= curType->getBasicType();
 		Precision	precision	= curType->getPrecision();

 		if (pathIter->type == VarTypeComponent::MATRIX_COLUMN)
 		{
 			basicType = getDataTypeFloatVec(getDataTypeMatrixNumRows(basicType));
 			++pathIter;
 		}

 		if (pathIter != end && pathIter->type == VarTypeComponent::VECTOR_COMPONENT)
 		{
 			basicType = getDataTypeScalarType(basicType);
 			++pathIter;
 		}

 		DE_ASSERT(pathIter == end);
 		return VarType(basicType, precision);
 	}
 	else
 		return VarType(*curType);
 }

 } // glu

 #endif // _GLUVARTYPEUTIL_HPP
	#ifndef _GLUVARTYPEUTIL_HPP
	#define _GLUVARTYPEUTIL_HPP
	/*-------------------------------------------------------------------------
	* drawElements Quality Program OpenGL ES Utilities
	* ------------------------------------------------
	*
	* Copyright 2014 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*
	//!
	* \file
	* \brief Shader variable type utilities.
	//--------------------------------------------------------------------*/

	#include "tcuDefs.hpp"
	#include "gluVarType.hpp"

	#include <vector>
	#include <string>
	#include <iterator>

	namespace glu
	{

	// Variable path tokenizer

	class VarTokenizer
	{
	public:
	enum Token
	{
	TOKEN_IDENTIFIER = 0,
	TOKEN_LEFT_BRACKET,
	TOKEN_RIGHT_BRACKET,
	TOKEN_PERIOD,
	TOKEN_NUMBER,
	TOKEN_END,

	TOKEN_LAST
	};

	VarTokenizer (const char* str);
	~VarTokenizer (void) {}

	Token getToken (void) const { return m_token; }
	std::string getIdentifier (void) const { return std::string(m_str+m_tokenStart, m_str+m_tokenStart+m_tokenLen); }
	int getNumber (void) const;
	int getCurrentTokenStartLocation (void) const { return m_tokenStart; }
	int getCurrentTokenEndLocation (void) const { return m_tokenStart + m_tokenLen; }
	void advance (void);

	private:
	const char* m_str;

	Token m_token;
	int m_tokenStart;
	int m_tokenLen;
	};

	// VarType subtype path utilities.

	struct VarTypeComponent
	{
	enum Type
	{
	STRUCT_MEMBER = 0,
	ARRAY_ELEMENT,
	MATRIX_COLUMN,
	VECTOR_COMPONENT,

	VTCTYPE_LAST
	};

	VarTypeComponent (Type type_, int index_) : type(type_), index(index_) {}
	VarTypeComponent (void) : type(VTCTYPE_LAST), index(0) {}

	bool operator== (const VarTypeComponent& other) const { return type == other.type && index == other.index; }
	bool operator!= (const VarTypeComponent& other) const { return type != other.type \|\| index != other.index; }

	Type type;
	int index;
	};

	typedef std::vector<VarTypeComponent> TypeComponentVector;

	// TypeComponentVector utilties.

	template <typename Iterator>
	bool isValidTypePath (const VarType& type, Iterator begin, Iterator end);

	template <typename Iterator>
	VarType getVarType (const VarType& type, Iterator begin, Iterator end);

	inline bool isValidTypePath (const VarType& type, const TypeComponentVector& path) { return isValidTypePath(type, path.begin(), path.end()); }
	inline VarType getVarType (const VarType& type, const TypeComponentVector& path) { return getVarType(type, path.begin(), path.end()); }

	std::string parseVariableName (const char* nameWithPath);
	void parseTypePath (const char* nameWithPath, const VarType& type, TypeComponentVector& path);

	// Type path formatter.

	struct TypeAccessFormat
	{
	TypeAccessFormat (const VarType& type_, const TypeComponentVector& path_) : type(type_), path(path_) {}

	const VarType& type;
	const TypeComponentVector& path;
	};

	std::ostream& operator<< (std::ostream& str, const TypeAccessFormat& format);

	// Subtype path builder.

	class SubTypeAccess
	{
	public:
	SubTypeAccess (const VarType& type);

	SubTypeAccess& member (int ndx) { m_path.push_back(VarTypeComponent(VarTypeComponent::STRUCT_MEMBER, ndx)); DE_ASSERT(isValid()); return *this; } //!< Access struct element.
	SubTypeAccess& element (int ndx) { m_path.push_back(VarTypeComponent(VarTypeComponent::ARRAY_ELEMENT, ndx)); DE_ASSERT(isValid()); return *this; } //!< Access array element.
	SubTypeAccess& column (int ndx) { m_path.push_back(VarTypeComponent(VarTypeComponent::MATRIX_COLUMN, ndx)); DE_ASSERT(isValid()); return *this; } //!< Access column.
	SubTypeAccess& component (int ndx) { m_path.push_back(VarTypeComponent(VarTypeComponent::VECTOR_COMPONENT, ndx)); DE_ASSERT(isValid()); return *this; } //!< Access component.
	SubTypeAccess& parent (void) { DE_ASSERT(!m_path.empty()); m_path.pop_back(); return *this; }

	SubTypeAccess member (int ndx) const { return SubTypeAccess(*this).member(ndx); }
	SubTypeAccess element (int ndx) const { return SubTypeAccess(*this).element(ndx); }
	SubTypeAccess column (int ndx) const { return SubTypeAccess(*this).column(ndx); }
	SubTypeAccess component (int ndx) const { return SubTypeAccess(*this).component(ndx); }
	SubTypeAccess parent (void) const { return SubTypeAccess(*this).parent(); }

	bool isValid (void) const { return isValidTypePath(m_type, m_path); }
	VarType getType (void) const { return getVarType(m_type, m_path); }
	const TypeComponentVector& getPath (void) const { return m_path; }

	bool empty (void) const { return m_path.empty(); }

	bool operator== (const SubTypeAccess& other) const { return m_path == other.m_path && m_type == other.m_type; }
	bool operator!= (const SubTypeAccess& other) const { return m_path != other.m_path \|\| m_type != other.m_type; }

	private:
	VarType m_type;
	TypeComponentVector m_path;
	};

	// Subtype iterator.

	// \note VarType must be live during iterator usage.
	template <class IsExpanded>
	class SubTypeIterator : public std::iterator<std::forward_iterator_tag, VarType>
	{
	public:
	static SubTypeIterator<IsExpanded> begin (const VarType* type) { return SubTypeIterator(type); }
	static SubTypeIterator<IsExpanded> end (const VarType* type) { DE_UNREF(type); return SubTypeIterator(DE_NULL); }

	bool operator== (const SubTypeIterator<IsExpanded>& other) const { return m_type == other.m_type && m_path == other.m_path; }
	bool operator!= (const SubTypeIterator<IsExpanded>& other) const { return m_type != other.m_type \|\| m_path != other.m_path; }

	SubTypeIterator<IsExpanded>& operator++ (void);
	SubTypeIterator<IsExpanded> operator++ (int) { SubTypeIterator<IsExpanded> copy(this); ++(this); return copy; }

	void toStream (std::ostream& str) const { str << TypeAccessFormat(*m_type, m_path); }
	VarType getType (void) const { return getVarType(*m_type, m_path.begin(), m_path.end()); }
	const TypeComponentVector& getPath (void) const { return m_path; }

	VarType operator* (void) const { return getType(); }

	private:
	SubTypeIterator (const VarType* type);

	void removeTraversed (void);
	void findNext (void);

	const VarType* m_type;
	TypeComponentVector m_path;
	};

	struct IsBasicType { bool operator() (const VarType& type) const { return type.isBasicType(); } };
	struct IsScalarType { bool operator() (const VarType& type) const { return type.isBasicType() && isDataTypeScalar(type.getBasicType()); } };
	struct IsVectorOrScalarType { bool operator() (const VarType& type) const { return type.isBasicType() && isDataTypeScalarOrVector(type.getBasicType()); } };

	typedef SubTypeIterator<IsBasicType> BasicTypeIterator;
	typedef SubTypeIterator<IsVectorOrScalarType> VectorTypeIterator;
	typedef SubTypeIterator<IsScalarType> ScalarTypeIterator;

	template <class IsExpanded>
	std::ostream& operator<< (std::ostream& str, const SubTypeIterator<IsExpanded>& iter)
	{
	iter.toStream(str);
	return str;
	}

	template <class IsExpanded>
	SubTypeIterator<IsExpanded>::SubTypeIterator (const VarType* type)
	: m_type(type)
	{
	if (m_type)
	findNext();
	}

	template <class IsExpanded>
	SubTypeIterator<IsExpanded>& SubTypeIterator<IsExpanded>::operator++ (void)
	{
	if (!m_path.empty())
	{
	// Remove traversed nodes.
	removeTraversed();

	if (!m_path.empty())
	findNext();
	else
	m_type = DE_NULL; // Unset type to signal end.
	}
	else
	{
	// First type was already expanded.
	DE_ASSERT(IsExpanded()(getVarType(*m_type, m_path)));
	m_type = DE_NULL;
	}

	return *this;
	}

	template <class IsExpanded>
	void SubTypeIterator<IsExpanded>::removeTraversed (void)
	{
	DE_ASSERT(m_type && !m_path.empty());

	// Pop traversed nodes.
	while (!m_path.empty())
	{
	VarTypeComponent& curComp = m_path.back();
	VarType parentType = getVarType(*m_type, m_path.begin(), m_path.end()-1);

	if (curComp.type == VarTypeComponent::MATRIX_COLUMN)
	{
	DE_ASSERT(isDataTypeMatrix(parentType.getBasicType()));
	if (curComp.index+1 < getDataTypeMatrixNumColumns(parentType.getBasicType()))
	break;
	}
	else if (curComp.type == VarTypeComponent::VECTOR_COMPONENT)
	{
	DE_ASSERT(isDataTypeVector(parentType.getBasicType()));
	if (curComp.index+1 < getDataTypeScalarSize(parentType.getBasicType()))
	break;
	}
	else if (curComp.type == VarTypeComponent::ARRAY_ELEMENT)
	{
	DE_ASSERT(parentType.isArrayType());
	if (curComp.index+1 < parentType.getArraySize())
	break;
	}
	else if (curComp.type == VarTypeComponent::STRUCT_MEMBER)
	{
	DE_ASSERT(parentType.isStructType());
	if (curComp.index+1 < parentType.getStructPtr()->getNumMembers())
	break;
	}

	m_path.pop_back();
	}
	}

	template <class IsExpanded>
	void SubTypeIterator<IsExpanded>::findNext (void)
	{
	if (!m_path.empty())
	{
	// Increment child counter in current level.
	VarTypeComponent& curComp = m_path.back();
	curComp.index += 1;
	}

	for (;;)
	{
	VarType curType = getVarType(*m_type, m_path);

	if (IsExpanded()(curType))
	break;

	// Recurse into child type.
	if (curType.isBasicType())
	{
	DataType basicType = curType.getBasicType();

	if (isDataTypeMatrix(basicType))
	m_path.push_back(VarTypeComponent(VarTypeComponent::MATRIX_COLUMN, 0));
	else if (isDataTypeVector(basicType))
	m_path.push_back(VarTypeComponent(VarTypeComponent::VECTOR_COMPONENT, 0));
	else
	DE_ASSERT(false); // Can't expand scalars - IsExpanded() is buggy.
	}
	else if (curType.isArrayType())
	m_path.push_back(VarTypeComponent(VarTypeComponent::ARRAY_ELEMENT, 0));
	else if (curType.isStructType())
	m_path.push_back(VarTypeComponent(VarTypeComponent::STRUCT_MEMBER, 0));
	else
	DE_ASSERT(false);
	}
	}

	template <typename Iterator>
	bool isValidTypePath (const VarType& type, Iterator begin, Iterator end)
	{
	const VarType* curType = &type;
	Iterator pathIter = begin;

	// Process struct member and array element parts of path.
	while (pathIter != end)
	{
	if (pathIter->type == VarTypeComponent::STRUCT_MEMBER)
	{
	if (!curType->isStructType() \|\| !de::inBounds(pathIter->index, 0, curType->getStructPtr()->getNumMembers()))
	return false;

	curType = &curType->getStructPtr()->getMember(pathIter->index).getType();
	}
	else if (pathIter->type == VarTypeComponent::ARRAY_ELEMENT)
	{
	if (!curType->isArrayType() \|\| (curType->getArraySize() != VarType::UNSIZED_ARRAY && !de::inBounds(pathIter->index, 0, curType->getArraySize())))
	return false;

	curType = &curType->getElementType();
	}
	else
	break;

	++pathIter;
	}

	if (pathIter != end)
	{
	DE_ASSERT(pathIter->type == VarTypeComponent::MATRIX_COLUMN \|\| pathIter->type == VarTypeComponent::VECTOR_COMPONENT);

	// Current type should be basic type.
	if (!curType->isBasicType())
	return false;

	DataType basicType = curType->getBasicType();

	if (pathIter->type == VarTypeComponent::MATRIX_COLUMN)
	{
	if (!isDataTypeMatrix(basicType))
	return false;

	basicType = getDataTypeFloatVec(getDataTypeMatrixNumRows(basicType));
	++pathIter;
	}

	if (pathIter != end && pathIter->type == VarTypeComponent::VECTOR_COMPONENT)
	{
	if (!isDataTypeVector(basicType))
	return false;

	basicType = getDataTypeScalarType(basicType);
	++pathIter;
	}
	}

	return pathIter == end;
	}

	template <typename Iterator>
	VarType getVarType (const VarType& type, Iterator begin, Iterator end)
	{
	TCU_CHECK(isValidTypePath(type, begin, end));

	const VarType* curType = &type;
	Iterator pathIter = begin;

	// Process struct member and array element parts of path.
	while (pathIter != end)
	{
	if (pathIter->type == VarTypeComponent::STRUCT_MEMBER)
	curType = &curType->getStructPtr()->getMember(pathIter->index).getType();
	else if (pathIter->type == VarTypeComponent::ARRAY_ELEMENT)
	curType = &curType->getElementType();
	else
	break;

	++pathIter;
	}

	if (pathIter != end)
	{
	DataType basicType = curType->getBasicType();
	Precision precision = curType->getPrecision();

	if (pathIter->type == VarTypeComponent::MATRIX_COLUMN)
	{
	basicType = getDataTypeFloatVec(getDataTypeMatrixNumRows(basicType));
	++pathIter;
	}

	if (pathIter != end && pathIter->type == VarTypeComponent::VECTOR_COMPONENT)
	{
	basicType = getDataTypeScalarType(basicType);
	++pathIter;
	}

	DE_ASSERT(pathIter == end);
	return VarType(basicType, precision);
	}
	else
	return VarType(*curType);
	}

	} // glu

	#endif // _GLUVARTYPEUTIL_HPP