//-----------------------------------------------------------------------------
// File:		LPVPacking.usf
//
// Summary:		Common functionality for LPV compute shaders
//
// Created:		2015-04-15
//
// Author:		Ben Woodhouse - mailto:benwood@microsoft.com
//
//				Copyright (C) Microsoft. All rights reserved.
//-----------------------------------------------------------------------------

//------------------------------------------------------------------------------

struct LPVCellPacked
{
	uint packedCoeffs[14];
};

//-------------------------------------------------------------------------------------------------

//-------------------------------------------------------------------------------------------------

LPVCellPacked PackLPVCell( LPVCell cellIn )
{
	LPVCellPacked cellOut;
	uint3 compressedCoeffs[9]; 
	[unroll]
	for ( int i=0; i<9; i++ )
	{
		compressedCoeffs[i] = f32tof16( cellIn.coeffs[i] );
	}
	uint compressedAO = f32tof16( cellIn.AO );
	
	cellOut.packedCoeffs[0] = compressedCoeffs[0].x | ( compressedCoeffs[0].y << 16 );
	cellOut.packedCoeffs[1] = compressedCoeffs[0].z | ( compressedCoeffs[1].x << 16 );
	cellOut.packedCoeffs[2] = compressedCoeffs[1].y | ( compressedCoeffs[1].z << 16 );

	cellOut.packedCoeffs[3] = compressedCoeffs[2].x | ( compressedCoeffs[2].y << 16 );
	cellOut.packedCoeffs[4] = compressedCoeffs[2].z | ( compressedCoeffs[3].x << 16 );
	cellOut.packedCoeffs[5] = compressedCoeffs[3].y | ( compressedCoeffs[3].z << 16 );

	cellOut.packedCoeffs[6] = compressedCoeffs[4].x | ( compressedCoeffs[4].y << 16 );
	cellOut.packedCoeffs[7] = compressedCoeffs[4].z | ( compressedCoeffs[5].x << 16 );
	cellOut.packedCoeffs[8] = compressedCoeffs[5].y | ( compressedCoeffs[5].z << 16 );

	cellOut.packedCoeffs[9] = compressedCoeffs[6].x | ( compressedCoeffs[6].y << 16 );
	cellOut.packedCoeffs[10] = compressedCoeffs[6].z | ( compressedCoeffs[7].x << 16 );
	cellOut.packedCoeffs[11] = compressedCoeffs[7].y | ( compressedCoeffs[7].z << 16 );

	cellOut.packedCoeffs[12] = compressedCoeffs[8].x | ( compressedCoeffs[8].y << 16 );
	cellOut.packedCoeffs[13] = compressedCoeffs[8].z | ( compressedAO << 16 );


	return cellOut;
}

//-------------------------------------------------------------------------------------------------

LPVCell UnpackLPVCell( LPVCellPacked cellPacked )
{
	LPVCell cellOut;
	uint3 compressedCoeffs;
	compressedCoeffs.x = cellPacked.packedCoeffs[0];
	compressedCoeffs.y = cellPacked.packedCoeffs[0] >> 16;
	compressedCoeffs.z = cellPacked.packedCoeffs[1];
	cellOut.coeffs[0] = f16tof32( compressedCoeffs );

	compressedCoeffs.x = cellPacked.packedCoeffs[1] >> 16;
	compressedCoeffs.y = cellPacked.packedCoeffs[2];
	compressedCoeffs.z = cellPacked.packedCoeffs[2] >> 16;
	cellOut.coeffs[1] = f16tof32( compressedCoeffs );

	compressedCoeffs.x = cellPacked.packedCoeffs[3];
	compressedCoeffs.y = cellPacked.packedCoeffs[3] >> 16;
	compressedCoeffs.z = cellPacked.packedCoeffs[4];
	cellOut.coeffs[2] = f16tof32( compressedCoeffs );

	compressedCoeffs.x = cellPacked.packedCoeffs[4] >> 16;
	compressedCoeffs.y = cellPacked.packedCoeffs[5];
	compressedCoeffs.z = cellPacked.packedCoeffs[5] >> 16;
	cellOut.coeffs[3] = f16tof32( compressedCoeffs );

	compressedCoeffs.x = cellPacked.packedCoeffs[6];
	compressedCoeffs.y = cellPacked.packedCoeffs[6] >> 16;
	compressedCoeffs.z = cellPacked.packedCoeffs[7];
	cellOut.coeffs[4] = f16tof32( compressedCoeffs );

	compressedCoeffs.x = cellPacked.packedCoeffs[7] >> 16;
	compressedCoeffs.y = cellPacked.packedCoeffs[8];
	compressedCoeffs.z = cellPacked.packedCoeffs[8] >> 16;
	cellOut.coeffs[5] = f16tof32( compressedCoeffs );

	compressedCoeffs.x = cellPacked.packedCoeffs[9];
	compressedCoeffs.y = cellPacked.packedCoeffs[9] >> 16;
	compressedCoeffs.z = cellPacked.packedCoeffs[10];
	cellOut.coeffs[6] = f16tof32( compressedCoeffs );

	compressedCoeffs.x = cellPacked.packedCoeffs[10] >> 16;
	compressedCoeffs.y = cellPacked.packedCoeffs[11];
	compressedCoeffs.z = cellPacked.packedCoeffs[11] >> 16;
	cellOut.coeffs[7] = f16tof32( compressedCoeffs );

	compressedCoeffs.x = cellPacked.packedCoeffs[12];
	compressedCoeffs.y = cellPacked.packedCoeffs[12] >> 16;
	compressedCoeffs.z = cellPacked.packedCoeffs[13];
	cellOut.coeffs[8] = f16tof32( compressedCoeffs );

	cellOut.AO = f16tof32( cellPacked.packedCoeffs[13] >> 16 );

	return cellOut;
}