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1 /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
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2
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3 /*
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4 Sonic Visualiser
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5 An audio file viewer and annotation editor.
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6 Centre for Digital Music, Queen Mary, University of London.
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7 This file copyright 2006 Chris Cannam.
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8
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9 This program is free software; you can redistribute it and/or
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10 modify it under the terms of the GNU General Public License as
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11 published by the Free Software Foundation; either version 2 of the
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12 License, or (at your option) any later version. See the file
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13 COPYING included with this distribution for more information.
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14 */
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15
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16 #include "PowerOfTwoZoomConstraint.h"
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17
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18 int
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19 PowerOfTwoZoomConstraint::getNearestBlockSize(int req,
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20 RoundingDirection dir) const
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21 {
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22 int result = 0;
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23
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24 for (int bs = 1; ; bs *= 2) {
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25 if (bs >= req) {
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26 if (dir == RoundNearest) {
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27 if (bs - req < req - bs/2) {
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28 result = bs;
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29 break;
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30 } else {
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31 result = bs/2;
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32 break;
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33 }
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34 } else if (dir == RoundDown) {
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35 result = bs/2;
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36 break;
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37 } else {
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38 result = bs;
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39 break;
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40 }
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41 }
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42 }
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43
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44 if (result > getMaxZoomLevel()) result = getMaxZoomLevel();
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45 return result;
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46 }
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47
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