//////////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2004, Industrial Light & Magic, a division of Lucasfilm
// Entertainment Company Ltd.  Portions contributed and copyright held by
// others as indicated.  All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above
//       copyright notice, this list of conditions and the following
//       disclaimer.
//
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided with
//       the distribution.
//
//     * Neither the name of Industrial Light & Magic nor the names of
//       any other contributors to this software may be used to endorse or
//       promote products derived from this software without specific prior
//       written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
//////////////////////////////////////////////////////////////////////////////

#include <compareFloat.h>

using namespace Imf;


bool
equivalent (float f1, float f2, Compression comp)
{
    //
    // Test if a float, f1, is "equivalent" to another float, f2,
    // which results from storing f1 in an image file, and reading
    // it back:
    // If the file was compressed with PXR24_COMPRESSION, then f1
    // and f2 must the same as f1 rounded to 24 bits (see class
    // ImfPxr24Compressor); otherwise f1 and f2 must be the same.
    //

    union
    {
	float		f;
	unsigned int	i;
    } u1, u2;

    u1.f = f1;
    u2.f = f2;

    if (comp == PXR24_COMPRESSION)
	return (u2.i >> 8) - (u1.i >> 8) < 2;
    else
	return u2.i == u1.i;
}
