Mercurial > hg > svgui
view layer/ScrollableMagRangeCache.h @ 1194:be5e43e2180c levelpanwidget
Record scale factor in log
author | Chris Cannam |
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date | Thu, 15 Dec 2016 16:29:18 +0000 |
parents | c53ed1a6fcbd |
children | a34a2a25907c |
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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. */ #ifndef SCROLLABLE_MAG_RANGE_CACHE_H #define SCROLLABLE_MAG_RANGE_CACHE_H #include "base/BaseTypes.h" #include "base/MagnitudeRange.h" #include "LayerGeometryProvider.h" /** * A cached set of magnitude range records for a view that scrolls * horizontally, such as a spectrogram. The cache object holds a * magnitude range per column of the view, can report width (likely * the same as the underlying view, but it's the caller's * responsibility to set the size appropriately), can scroll the set * of ranges, and can report and update which columns have had a range * specified. * * The only way to *update* the valid area in a cache is to update the * magnitude range for a column using the sampleColumn call. */ class ScrollableMagRangeCache { public: ScrollableMagRangeCache() : m_startFrame(0), m_zoomLevel(0) {} void invalidate() { m_ranges = std::vector<MagnitudeRange>(m_ranges.size()); } int getWidth() const { return int(m_ranges.size()); } /** * Set the width of the cache in columns. If the new size differs * from the current size, the cache is invalidated. */ void resize(int newWidth) { if (getWidth() != newWidth) { m_ranges = std::vector<MagnitudeRange>(newWidth); } } int getZoomLevel() const { return m_zoomLevel; } /** * Set the zoom level. If the new zoom level differs from the * current one, the cache is invalidated. (Determining whether to * invalidate the cache here is the only thing the zoom level is * used for.) */ void setZoomLevel(int zoom) { if (m_zoomLevel != zoom) { m_zoomLevel = zoom; invalidate(); } } sv_frame_t getStartFrame() const { return m_startFrame; } /** * Set the start frame. If the new start frame differs from the * current one, the cache is invalidated. To scroll, i.e. to set * the start frame while retaining cache validity where possible, * use scrollTo() instead. */ void setStartFrame(sv_frame_t frame) { if (m_startFrame != frame) { m_startFrame = frame; invalidate(); } } bool isColumnSet(int column) const { return in_range_for(m_ranges, column) && m_ranges.at(column).isSet(); } bool areColumnsSet(int x, int count) const { for (int i = 0; i < count; ++i) { if (!isColumnSet(x + i)) return false; } return true; } /** * Get the magnitude range for a single column. */ MagnitudeRange getRange(int column) const { return m_ranges.at(column); } /** * Get the magnitude range for a range of columns. */ MagnitudeRange getRange(int x, int count) const; /** * Set the new start frame for the cache, according to the * geometry of the supplied LayerGeometryProvider, if possible * also moving along any existing valid data within the cache so * that it continues to be valid for the new start frame. */ void scrollTo(const LayerGeometryProvider *v, sv_frame_t newStartFrame); /** * Update a column in the cache, by column index. (Column zero is * the first column in the cache, it has nothing to do with any * underlying model that the cache may be used with.) */ void sampleColumn(int column, const MagnitudeRange &r); private: std::vector<MagnitudeRange> m_ranges; sv_frame_t m_startFrame; int m_zoomLevel; }; #endif