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d5f74e42d6
License statement text corrected; compiler warnings caused by Bison 2.41 disabled for MSVC; a few other compiler warnings on 54-bit Windows eliminated by appropriate type cast Wrong license statements corrected in several files. Copyright and license statements added in XSD and GLSL files. Copyright year updated in some files. Obsolete documentation files removed from DrawResources.
54 lines
1.9 KiB
C++
54 lines
1.9 KiB
C++
// Created on: 1993-01-14
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// Created by: Remi LEQUETTE
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// Copyright (c) 1993-1999 Matra Datavision
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// Copyright (c) 1999-2014 OPEN CASCADE SAS
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//
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// This file is part of Open CASCADE Technology software library.
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//
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// This library is free software; you can redistribute it and/or modify it under
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// the terms of the GNU Lesser General Public License version 2.1 as published
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// by the Free Software Foundation, with special exception defined in the file
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// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
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// distribution for complete text of the license and disclaimer of any warranty.
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//
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// Alternatively, this file may be used under the terms of Open CASCADE
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// commercial license or contractual agreement.
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#include <TCollection.ixx>
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// The array of prime numbers used as consequtive steps for
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// size of array of buckets in the map.
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// The prime numbers are used for array size with the hope that this will
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// lead to less probablility of having the same hash codes for
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// different map items (note that all hash codes are modulo that size).
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// The value of each next step is chosen to be ~2 times greater than previous.
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// Though this could be thought as too much, actually the amount of
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// memory overhead in that case is only ~15% as compared with total size of
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// all auxiliary data structures (each map node takes ~24 bytes),
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// and this proves to pay off in performance (see OCC13189).
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#define NB_PRIMES 12
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static const Standard_Integer Primes[NB_PRIMES+1] = {
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101,
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1009,
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2003,
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5003,
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10007,
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20011,
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37003,
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57037,
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65003,
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100019,
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209953, // The following are Pierpont primes taken from Wikipedia [List of prime numbers]
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472393,
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995329
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};
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Standard_Integer TCollection::NextPrimeForMap(const Standard_Integer N)
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{
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Standard_Integer i;
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for (i = 0; i < NB_PRIMES; i++)
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if (Primes[i] > N) break;
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return Primes[i];
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}
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