EasyGen/libs/openexr-2.0.0/IlmImfTest/compareFloat.cpp

69 lines
2.6 KiB
C++

//////////////////////////////////////////////////////////////////////////////
//
// 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 OPENEXR_IMF_NAMESPACE;
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;
}