/*-------------------------------------------------------------------------
 * drawElements Quality Program Reference Renderer
 * -----------------------------------------------
 *
 * 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 Vertex attribute fetch.
 *//*--------------------------------------------------------------------*/

#include "rrVertexAttrib.hpp"
#include "tcuFloat.hpp"
#include "deInt32.h"
#include "deMemory.h"

namespace rr
{

namespace
{

struct NormalOrder
{
	enum
	{
		T0 = 0,
		T1 = 1,
		T2 = 2,
		T3 = 3,
	};
};

struct BGRAOrder
{
	enum
	{
		T0 = 2,
		T1 = 1,
		T2 = 0,
		T3 = 3,
	};
};

// readers

template<typename SrcScalarType, typename DstScalarType, typename Order>
inline void readOrder (typename tcu::Vector<DstScalarType, 4>& dst, const int size, const void* ptr)
{
	SrcScalarType aligned[4];
	deMemcpy(aligned, ptr, size * sizeof(SrcScalarType));

				   dst[Order::T0] = DstScalarType(aligned[0]);
	if (size >= 2) dst[Order::T1] = DstScalarType(aligned[1]);
	if (size >= 3) dst[Order::T2] = DstScalarType(aligned[2]);
	if (size >= 4) dst[Order::T3] = DstScalarType(aligned[3]);
}

template<typename SrcScalarType, typename Order>
inline void readUnormOrder (tcu::Vec4& dst, const int size, const void* ptr)
{
	const deUint32 range = (deUint32)((1ull << (sizeof(SrcScalarType)*8))-1);

	SrcScalarType aligned[4];
	deMemcpy(aligned, ptr, size * sizeof(SrcScalarType));

				   dst[Order::T0] = float(aligned[0]) / float(range);
	if (size >= 2) dst[Order::T1] = float(aligned[1]) / float(range);
	if (size >= 3) dst[Order::T2] = float(aligned[2]) / float(range);
	if (size >= 4) dst[Order::T3] = float(aligned[3]) / float(range);
}

template<typename SrcScalarType>
inline void readSnormClamp (tcu::Vec4& dst, const int size, const void* ptr)
{
	// Clamped formats, GLES3-style conversion: max{c / (2^(b-1) - 1), -1 }
	const deUint32 range = (deUint32)((1ull << (sizeof(SrcScalarType)*8-1))-1);

	SrcScalarType aligned[4];
	deMemcpy(aligned, ptr, size * sizeof(SrcScalarType));

				   dst[0] = de::max(-1.0f, float(aligned[0]) / float(range));
	if (size >= 2) dst[1] = de::max(-1.0f, float(aligned[1]) / float(range));
	if (size >= 3) dst[2] = de::max(-1.0f, float(aligned[2]) / float(range));
	if (size >= 4) dst[3] = de::max(-1.0f, float(aligned[3]) / float(range));
}

template<typename SrcScalarType>
inline void readSnormScale (tcu::Vec4& dst, const int size, const void* ptr)
{
	// Scaled formats, GLES2-style conversion: (2c + 1) / (2^b - 1)
	const deUint32 range = (deUint32)((1ull << (sizeof(SrcScalarType)*8))-1);

	SrcScalarType aligned[4];
	deMemcpy(aligned, ptr, size * sizeof(SrcScalarType));

				   dst[0] = (float(aligned[0]) * 2.0f + 1.0f) / float(range);
	if (size >= 2) dst[1] = (float(aligned[1]) * 2.0f + 1.0f) / float(range);
	if (size >= 3) dst[2] = (float(aligned[2]) * 2.0f + 1.0f) / float(range);
	if (size >= 4) dst[3] = (float(aligned[3]) * 2.0f + 1.0f) / float(range);
}

inline void readHalf (tcu::Vec4& dst, const int size, const void* ptr)
{
	deUint16 aligned[4];
	deMemcpy(aligned, ptr, size * sizeof(deUint16));

				   dst[0] = tcu::Float16(aligned[0]).asFloat();
	if (size >= 2) dst[1] = tcu::Float16(aligned[1]).asFloat();
	if (size >= 3) dst[2] = tcu::Float16(aligned[2]).asFloat();
	if (size >= 4) dst[3] = tcu::Float16(aligned[3]).asFloat();
}

inline void readFixed (tcu::Vec4& dst, const int size, const void* ptr)
{
	deInt32 aligned[4];
	deMemcpy(aligned, ptr, size * sizeof(deInt32));

				   dst[0] = aligned[0] / float(1 << 16);
	if (size >= 2) dst[1] = aligned[1] / float(1 << 16);
	if (size >= 3) dst[2] = aligned[2] / float(1 << 16);
	if (size >= 4) dst[3] = aligned[3] / float(1 << 16);
}

inline void readDouble (tcu::Vec4& dst, const int size, const void* ptr)
{
	double aligned[4];
	deMemcpy(aligned, ptr, size * sizeof(double));

				   dst[0] = float(aligned[0]);
	if (size >= 2) dst[1] = float(aligned[1]);
	if (size >= 3) dst[2] = float(aligned[2]);
	if (size >= 4) dst[3] = float(aligned[3]);
}

template <int integerLen>
inline deInt32 extendSign (deUint32 integer)
{
	return deUint32(0 - deInt32((integer & (1 << (integerLen - 1))) << 1)) | integer;
}

template<typename DstScalarType>
inline void readUint2101010Rev (typename tcu::Vector<DstScalarType, 4>& dst, const int size, const void* ptr)
{
	deUint32 aligned;
	deMemcpy(&aligned, ptr, sizeof(deUint32));

				   dst[0] = DstScalarType((aligned >>  0) & ((1 << 10) - 1));
	if (size >= 2) dst[1] = DstScalarType((aligned >> 10) & ((1 << 10) - 1));
	if (size >= 3) dst[2] = DstScalarType((aligned >> 20) & ((1 << 10) - 1));
	if (size >= 4) dst[3] = DstScalarType((aligned >> 30) & ((1 <<  2) - 1));
}

template<typename DstScalarType>
inline void readInt2101010Rev (typename tcu::Vector<DstScalarType, 4>& dst, const int size, const void* ptr)
{
	deUint32 aligned;
	deMemcpy(&aligned, ptr, sizeof(deUint32));

				   dst[0] = (DstScalarType)extendSign<10>((aligned >>  0) & ((1 << 10) - 1));
	if (size >= 2) dst[1] = (DstScalarType)extendSign<10>((aligned >> 10) & ((1 << 10) - 1));
	if (size >= 3) dst[2] = (DstScalarType)extendSign<10>((aligned >> 20) & ((1 << 10) - 1));
	if (size >= 4) dst[3] = (DstScalarType)extendSign< 2>((aligned >> 30) & ((1 <<  2) - 1));
}

template<typename Order>
inline void readUnorm2101010RevOrder (tcu::Vec4& dst, const int size, const void* ptr)
{
	const deUint32 range10 = (deUint32)((1ull << 10)-1);
	const deUint32 range2 = (deUint32)((1ull <<  2)-1);

	deUint32 aligned;
	deMemcpy(&aligned, ptr, sizeof(deUint32));

				   dst[Order::T0] = float((aligned >>  0) & ((1 << 10) - 1)) / float(range10);
	if (size >= 2) dst[Order::T1] = float((aligned >> 10) & ((1 << 10) - 1)) / float(range10);
	if (size >= 3) dst[Order::T2] = float((aligned >> 20) & ((1 << 10) - 1)) / float(range10);
	if (size >= 4) dst[Order::T3] = float((aligned >> 30) & ((1 <<  2) - 1)) / float(range2);
}

template<typename Order>
inline void readSnorm2101010RevClampOrder (tcu::Vec4& dst, const int size, const void* ptr)
{
	// Clamped formats, GLES3-style conversion: max{c / (2^(b-1) - 1), -1 }
	const deUint32 range10 = (deUint32)((1ull << (10-1))-1);
	const deUint32 range2  = (deUint32)((1ull << ( 2-1))-1);

	deUint32 aligned;
	deMemcpy(&aligned, ptr, sizeof(deUint32));

				   dst[Order::T0] = de::max(-1.0f, float(extendSign<10>((aligned >>  0) & ((1 << 10) - 1))) / float(range10));
	if (size >= 2) dst[Order::T1] = de::max(-1.0f, float(extendSign<10>((aligned >> 10) & ((1 << 10) - 1))) / float(range10));
	if (size >= 3) dst[Order::T2] = de::max(-1.0f, float(extendSign<10>((aligned >> 20) & ((1 << 10) - 1))) / float(range10));
	if (size >= 4) dst[Order::T3] = de::max(-1.0f, float(extendSign< 2>((aligned >> 30) & ((1 <<  2) - 1))) / float(range2));
}

template<typename Order>
inline void readSnorm2101010RevScaleOrder (tcu::Vec4& dst, const int size, const void* ptr)
{
	// Scaled formats, GLES2-style conversion: (2c + 1) / (2^b - 1)
	const deUint32 range10 = (deUint32)((1ull << 10)-1);
	const deUint32 range2  = (deUint32)((1ull <<  2)-1);

	deUint32 aligned;
	deMemcpy(&aligned, ptr, sizeof(deUint32));

				   dst[Order::T0] = (float(extendSign<10>((aligned >>  0) & ((1 << 10) - 1)) * 2.0f + 1.0f) / float(range10));
	if (size >= 2) dst[Order::T1] = (float(extendSign<10>((aligned >> 10) & ((1 << 10) - 1)) * 2.0f + 1.0f) / float(range10));
	if (size >= 3) dst[Order::T2] = (float(extendSign<10>((aligned >> 20) & ((1 << 10) - 1)) * 2.0f + 1.0f) / float(range10));
	if (size >= 4) dst[Order::T3] = (float(extendSign< 2>((aligned >> 30) & ((1 <<  2) - 1)) * 2.0f + 1.0f) / float(range2));
}

// ordered readers

template<typename SrcScalarType, typename DstScalarType>
inline void read (typename tcu::Vector<DstScalarType, 4>& dst, const int size, const void* ptr)
{
	readOrder<SrcScalarType, DstScalarType, NormalOrder>(dst, size, ptr);
}

template<typename SrcScalarType>
inline void readUnorm (tcu::Vec4& dst, const int size, const void* ptr)
{
	readUnormOrder<SrcScalarType, NormalOrder>(dst, size, ptr);
}

template<typename SrcScalarType>
inline void readUnormBGRA (tcu::Vec4& dst, const int size, const void* ptr)
{
	readUnormOrder<SrcScalarType, BGRAOrder>(dst, size, ptr);
}

inline void readUnorm2101010Rev (tcu::Vec4& dst, const int size, const void* ptr)
{
	readUnorm2101010RevOrder<NormalOrder>(dst, size, ptr);
}

inline void readUnorm2101010RevBGRA (tcu::Vec4& dst, const int size, const void* ptr)
{
	readUnorm2101010RevOrder<BGRAOrder>(dst, size, ptr);
}

inline void readSnorm2101010RevClamp (tcu::Vec4& dst, const int size, const void* ptr)
{
	readSnorm2101010RevClampOrder<NormalOrder>(dst, size, ptr);
}

inline void readSnorm2101010RevClampBGRA (tcu::Vec4& dst, const int size, const void* ptr)
{
	readSnorm2101010RevClampOrder<BGRAOrder>(dst, size, ptr);
}

inline void readSnorm2101010RevScale (tcu::Vec4& dst, const int size, const void* ptr)
{
	readSnorm2101010RevScaleOrder<NormalOrder>(dst, size, ptr);
}

inline void readSnorm2101010RevScaleBGRA (tcu::Vec4& dst, const int size, const void* ptr)
{
	readSnorm2101010RevScaleOrder<BGRAOrder>(dst, size, ptr);
}

// utils

void readFloat (tcu::Vec4& dst, const VertexAttribType type, const int size, const void* ptr)
{
	switch (type)
	{
		case VERTEXATTRIBTYPE_FLOAT:									read<float>					(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_HALF:										readHalf					(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_FIXED:									readFixed					(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_DOUBLE:									readDouble					(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UNORM8:							readUnorm<deUint8>			(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UNORM16:							readUnorm<deUint16>			(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UNORM32:							readUnorm<deUint32>			(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV:				readUnorm2101010Rev			(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM8_CLAMP:						readSnormClamp<deInt8>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM16_CLAMP:					readSnormClamp<deInt16>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM32_CLAMP:					readSnormClamp<deInt32>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP:		readSnorm2101010RevClamp	(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM8_SCALE:						readSnormScale<deInt8>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM16_SCALE:					readSnormScale<deInt16>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM32_SCALE:					readSnormScale<deInt32>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE:		readSnorm2101010RevScale	(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UINT8:							read<deUint8>				(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UINT16:							read<deUint16>				(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UINT32:							read<deUint32>				(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_INT8:								read<deInt8>				(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_INT16:							read<deInt16>				(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_INT32:							read<deInt32>				(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UINT_2_10_10_10_REV:				readUint2101010Rev			(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_INT_2_10_10_10_REV:				readInt2101010Rev			(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UNORM8_BGRA:						readUnormBGRA<deUint8>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV_BGRA:		readUnorm2101010RevBGRA		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP_BGRA:	readSnorm2101010RevClampBGRA(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE_BGRA:	readSnorm2101010RevScaleBGRA(dst, size, ptr);	break;

		case VERTEXATTRIBTYPE_PURE_UINT8:
		case VERTEXATTRIBTYPE_PURE_UINT16:
		case VERTEXATTRIBTYPE_PURE_UINT32:
		case VERTEXATTRIBTYPE_PURE_INT8:
		case VERTEXATTRIBTYPE_PURE_INT16:
		case VERTEXATTRIBTYPE_PURE_INT32:
			DE_ASSERT(!"Invalid read");

		default:
			DE_ASSERT(false);
	}
}

void readInt (tcu::IVec4& dst, const VertexAttribType type, const int size, const void* ptr)
{
	switch (type)
	{
		case VERTEXATTRIBTYPE_PURE_INT8:				read<deInt8>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_PURE_INT16:				read<deInt16>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_PURE_INT32:				read<deInt32>		(dst, size, ptr);	break;

		case VERTEXATTRIBTYPE_FLOAT:
		case VERTEXATTRIBTYPE_HALF:
		case VERTEXATTRIBTYPE_FIXED:
		case VERTEXATTRIBTYPE_DOUBLE:
		case VERTEXATTRIBTYPE_NONPURE_UNORM8:
		case VERTEXATTRIBTYPE_NONPURE_UNORM16:
		case VERTEXATTRIBTYPE_NONPURE_UNORM32:
		case VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV:
		case VERTEXATTRIBTYPE_NONPURE_SNORM8_CLAMP:
		case VERTEXATTRIBTYPE_NONPURE_SNORM16_CLAMP:
		case VERTEXATTRIBTYPE_NONPURE_SNORM32_CLAMP:
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP:
		case VERTEXATTRIBTYPE_NONPURE_SNORM8_SCALE:
		case VERTEXATTRIBTYPE_NONPURE_SNORM16_SCALE:
		case VERTEXATTRIBTYPE_NONPURE_SNORM32_SCALE:
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE:
		case VERTEXATTRIBTYPE_NONPURE_UINT8:
		case VERTEXATTRIBTYPE_NONPURE_UINT16:
		case VERTEXATTRIBTYPE_NONPURE_UINT32:
		case VERTEXATTRIBTYPE_NONPURE_INT8:
		case VERTEXATTRIBTYPE_NONPURE_INT16:
		case VERTEXATTRIBTYPE_NONPURE_INT32:
		case VERTEXATTRIBTYPE_NONPURE_UINT_2_10_10_10_REV:
		case VERTEXATTRIBTYPE_NONPURE_INT_2_10_10_10_REV:
		case VERTEXATTRIBTYPE_PURE_UINT8:
		case VERTEXATTRIBTYPE_PURE_UINT16:
		case VERTEXATTRIBTYPE_PURE_UINT32:
		case VERTEXATTRIBTYPE_NONPURE_UNORM8_BGRA:
		case VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV_BGRA:
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP_BGRA:
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE_BGRA:
			DE_ASSERT(!"Invalid read");

		default:
			DE_ASSERT(false);
	}
}

void readUint (tcu::UVec4& dst, const VertexAttribType type, const int size, const void* ptr)
{
	switch (type)
	{
		case VERTEXATTRIBTYPE_PURE_UINT8:				read<deUint8>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_PURE_UINT16:				read<deUint16>		(dst, size, ptr);	break;
		case VERTEXATTRIBTYPE_PURE_UINT32:				read<deUint32>		(dst, size, ptr);	break;

		case VERTEXATTRIBTYPE_FLOAT:
		case VERTEXATTRIBTYPE_HALF:
		case VERTEXATTRIBTYPE_FIXED:
		case VERTEXATTRIBTYPE_DOUBLE:
		case VERTEXATTRIBTYPE_NONPURE_UNORM8:
		case VERTEXATTRIBTYPE_NONPURE_UNORM16:
		case VERTEXATTRIBTYPE_NONPURE_UNORM32:
		case VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV:
		case VERTEXATTRIBTYPE_NONPURE_SNORM8_CLAMP:
		case VERTEXATTRIBTYPE_NONPURE_SNORM16_CLAMP:
		case VERTEXATTRIBTYPE_NONPURE_SNORM32_CLAMP:
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP:
		case VERTEXATTRIBTYPE_NONPURE_SNORM8_SCALE:
		case VERTEXATTRIBTYPE_NONPURE_SNORM16_SCALE:
		case VERTEXATTRIBTYPE_NONPURE_SNORM32_SCALE:
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE:
		case VERTEXATTRIBTYPE_NONPURE_UINT8:
		case VERTEXATTRIBTYPE_NONPURE_UINT16:
		case VERTEXATTRIBTYPE_NONPURE_UINT32:
		case VERTEXATTRIBTYPE_NONPURE_INT8:
		case VERTEXATTRIBTYPE_NONPURE_INT16:
		case VERTEXATTRIBTYPE_NONPURE_INT32:
		case VERTEXATTRIBTYPE_NONPURE_UINT_2_10_10_10_REV:
		case VERTEXATTRIBTYPE_NONPURE_INT_2_10_10_10_REV:
		case VERTEXATTRIBTYPE_PURE_INT8:
		case VERTEXATTRIBTYPE_PURE_INT16:
		case VERTEXATTRIBTYPE_PURE_INT32:
		case VERTEXATTRIBTYPE_NONPURE_UNORM8_BGRA:
		case VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV_BGRA:
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP_BGRA:
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE_BGRA:
			DE_ASSERT(!"Invalid read");

		default:
			DE_ASSERT(false);
	}
}

int getComponentSize (const VertexAttribType type)
{
	switch (type)
	{
		case VERTEXATTRIBTYPE_FLOAT:									return 4;
		case VERTEXATTRIBTYPE_HALF:										return 2;
		case VERTEXATTRIBTYPE_FIXED:									return 4;
		case VERTEXATTRIBTYPE_DOUBLE:									return sizeof(double);
		case VERTEXATTRIBTYPE_NONPURE_UNORM8:							return 1;
		case VERTEXATTRIBTYPE_NONPURE_UNORM16:							return 2;
		case VERTEXATTRIBTYPE_NONPURE_UNORM32:							return 4;
		case VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV:				return sizeof(deUint32)/4;
		case VERTEXATTRIBTYPE_NONPURE_SNORM8_CLAMP:						return 1;
		case VERTEXATTRIBTYPE_NONPURE_SNORM16_CLAMP:					return 2;
		case VERTEXATTRIBTYPE_NONPURE_SNORM32_CLAMP:					return 4;
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP:		return sizeof(deUint32)/4;
		case VERTEXATTRIBTYPE_NONPURE_SNORM8_SCALE:						return 1;
		case VERTEXATTRIBTYPE_NONPURE_SNORM16_SCALE:					return 2;
		case VERTEXATTRIBTYPE_NONPURE_SNORM32_SCALE:					return 4;
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE:		return sizeof(deUint32)/4;
		case VERTEXATTRIBTYPE_NONPURE_UINT8:							return 1;
		case VERTEXATTRIBTYPE_NONPURE_UINT16:							return 2;
		case VERTEXATTRIBTYPE_NONPURE_UINT32:							return 4;
		case VERTEXATTRIBTYPE_NONPURE_INT8:								return 1;
		case VERTEXATTRIBTYPE_NONPURE_INT16:							return 2;
		case VERTEXATTRIBTYPE_NONPURE_INT32:							return 4;
		case VERTEXATTRIBTYPE_NONPURE_UINT_2_10_10_10_REV:				return sizeof(deUint32)/4;
		case VERTEXATTRIBTYPE_NONPURE_INT_2_10_10_10_REV:				return sizeof(deUint32)/4;
		case VERTEXATTRIBTYPE_PURE_UINT8:								return 1;
		case VERTEXATTRIBTYPE_PURE_UINT16:								return 2;
		case VERTEXATTRIBTYPE_PURE_UINT32:								return 4;
		case VERTEXATTRIBTYPE_PURE_INT8:								return 1;
		case VERTEXATTRIBTYPE_PURE_INT16:								return 2;
		case VERTEXATTRIBTYPE_PURE_INT32:								return 4;
		case VERTEXATTRIBTYPE_NONPURE_UNORM8_BGRA:						return 1;
		case VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV_BGRA:		return sizeof(deUint32)/4;
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP_BGRA:	return sizeof(deUint32)/4;
		case VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE_BGRA:	return sizeof(deUint32)/4;
		default:
			DE_ASSERT(false);
			return 0;
	}
}

} // anonymous

bool isValidVertexAttrib (const VertexAttrib& vertexAttrib)
{
	// Trivial range checks.
	if (!de::inBounds<int>(vertexAttrib.type, 0, VERTEXATTRIBTYPE_LAST) ||
		!de::inRange(vertexAttrib.size, 0, 4) ||
		vertexAttrib.instanceDivisor < 0)
		return false;

	// Generic attributes
	if (!vertexAttrib.pointer && vertexAttrib.type != VERTEXATTRIBTYPE_DONT_CARE)
		return false;

	// Packed formats
	if ((vertexAttrib.type == VERTEXATTRIBTYPE_NONPURE_INT_2_10_10_10_REV				||
		 vertexAttrib.type == VERTEXATTRIBTYPE_NONPURE_UINT_2_10_10_10_REV				||
		 vertexAttrib.type == VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV				||
		 vertexAttrib.type == VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP		||
		 vertexAttrib.type == VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE		||
		 vertexAttrib.type == VERTEXATTRIBTYPE_NONPURE_UNORM_2_10_10_10_REV_BGRA		||
		 vertexAttrib.type == VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_CLAMP_BGRA	||
		 vertexAttrib.type == VERTEXATTRIBTYPE_NONPURE_SNORM_2_10_10_10_REV_SCALE_BGRA)	&&
		vertexAttrib.size != 4)
		return false;

	return true;
}

void readVertexAttrib (tcu::Vec4& dst, const VertexAttrib& vertexAttrib, const int instanceNdx, const int vertexNdx)
{
	DE_ASSERT(isValidVertexAttrib(vertexAttrib));

	if (vertexAttrib.pointer)
	{
		const int	elementNdx		= (vertexAttrib.instanceDivisor != 0) ? (instanceNdx / vertexAttrib.instanceDivisor) : vertexNdx;
		const int	compSize		= getComponentSize(vertexAttrib.type);
		const int	stride			= (vertexAttrib.stride != 0) ? (vertexAttrib.stride) : (vertexAttrib.size*compSize);
		const int	byteOffset		= elementNdx*stride;

		dst = tcu::Vec4(0, 0, 0, 1); // defaults
		readFloat(dst, vertexAttrib.type, vertexAttrib.size, (const deUint8*)vertexAttrib.pointer + byteOffset);
	}
	else
	{
		dst = vertexAttrib.generic.get<float>();
	}
}

void readVertexAttrib (tcu::IVec4& dst, const VertexAttrib& vertexAttrib, const int instanceNdx, const int vertexNdx)
{
	DE_ASSERT(isValidVertexAttrib(vertexAttrib));

	if (vertexAttrib.pointer)
	{
		const int	elementNdx		= (vertexAttrib.instanceDivisor != 0) ? (instanceNdx / vertexAttrib.instanceDivisor) : vertexNdx;
		const int	compSize		= getComponentSize(vertexAttrib.type);
		const int	stride			= (vertexAttrib.stride != 0) ? (vertexAttrib.stride) : (vertexAttrib.size*compSize);
		const int	byteOffset		= elementNdx*stride;

		dst = tcu::IVec4(0, 0, 0, 1); // defaults
		readInt(dst, vertexAttrib.type, vertexAttrib.size, (const deUint8*)vertexAttrib.pointer + byteOffset);
	}
	else
	{
		dst = vertexAttrib.generic.get<deInt32>();
	}
}

void readVertexAttrib (tcu::UVec4& dst, const VertexAttrib& vertexAttrib, const int instanceNdx, const int vertexNdx)
{
	DE_ASSERT(isValidVertexAttrib(vertexAttrib));

	if (vertexAttrib.pointer)
	{
		const int	elementNdx		= (vertexAttrib.instanceDivisor != 0) ? (instanceNdx / vertexAttrib.instanceDivisor) : vertexNdx;
		const int	compSize		= getComponentSize(vertexAttrib.type);
		const int	stride			= (vertexAttrib.stride != 0) ? (vertexAttrib.stride) : (vertexAttrib.size*compSize);
		const int	byteOffset		= elementNdx*stride;

		dst = tcu::UVec4(0, 0, 0, 1); // defaults
		readUint(dst, vertexAttrib.type, vertexAttrib.size, (const deUint8*)vertexAttrib.pointer + byteOffset);
	}
	else
	{
		dst = vertexAttrib.generic.get<deUint32>();
	}
}

} // rr