Mercurial > hg > svcore
view data/model/RelativelyFineZoomConstraint.cpp @ 1621:cf5196881e3e single-point
Merge
author | Chris Cannam |
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date | Fri, 08 Mar 2019 13:37:08 +0000 |
parents | 05c3fbaec8ea |
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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ /* Sonic Visualiser An audio file viewer and annotation editor. Centre for Digital Music, Queen Mary, University of London. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. See the file COPYING included with this distribution for more information. */ #include "RelativelyFineZoomConstraint.h" #include <vector> #include <algorithm> #include <iostream> using namespace std; ZoomLevel RelativelyFineZoomConstraint::getNearestZoomLevel(ZoomLevel requested, RoundingDirection dir) const { static vector<int> levels; int maxLevel = getMaxZoomLevel().level; if (levels.empty()) { int level = 1; while (level <= maxLevel) { // cerr << level << " "; levels.push_back(level); int step = level / 10; int pwr = 0; while (step > 0) { ++pwr; step /= 2; } step = (1 << pwr); level += step; } // cerr << endl; } RoundingDirection effective = dir; if (requested.zone == ZoomLevel::PixelsPerFrame) { if (dir == RoundUp) effective = RoundDown; else if (dir == RoundDown) effective = RoundUp; } // iterator pointing to first level that is >= requested auto i = lower_bound(levels.begin(), levels.end(), requested.level); ZoomLevel newLevel(requested); if (i == levels.end()) { newLevel.level = maxLevel; } else if (*i == requested.level) { newLevel.level = requested.level; } else if (effective == RoundUp) { newLevel.level = *i; } else if (effective == RoundDown) { if (i != levels.begin()) { --i; } newLevel.level = *i; } else { // RoundNearest if (i != levels.begin()) { auto j = i; --j; if (requested.level - *j < *i - requested.level) { newLevel.level = *j; } else { newLevel.level = *i; } } } // canonicalise if (newLevel.level == 1) { newLevel.zone = ZoomLevel::FramesPerPixel; } using namespace std::rel_ops; if (newLevel > getMaxZoomLevel()) { newLevel = getMaxZoomLevel(); } else if (newLevel < getMinZoomLevel()) { newLevel = getMinZoomLevel(); } return newLevel; }