Mercurial > hg > svcore
view base/ZoomConstraint.h @ 299:576be0d0d218
* Merge transform directory from sv-match-alignment branch
(the previous comment included notes for this stuff, but I missed it
in the actual merge)
* Fix crash when a transform fails to create an output model and the
thread that created the transform then deletes its input model thinking
it's no longer needed, even though the transform run thread is still
using it -- fix is to wait() on the transform before returning the
null output model
author | Chris Cannam |
---|---|
date | Fri, 28 Sep 2007 16:15:06 +0000 |
parents | abaf3d7195ce |
children | 6a94bb528e9d |
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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 file copyright 2006 Chris Cannam. 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 _ZOOM_CONSTRAINT_H_ #define _ZOOM_CONSTRAINT_H_ #include <stdlib.h> /** * ZoomConstraint is a simple interface that describes a limitation on * the available zoom sizes for a view, for example based on cache * strategy or a (processing) window-size limitation. * * The default ZoomConstraint imposes no actual constraint except for * a nominal maximum. */ class ZoomConstraint { public: virtual ~ZoomConstraint() { } enum RoundingDirection { RoundDown, RoundUp, RoundNearest }; /** * Given the "ideal" block size (frames per pixel) for a given * zoom level, return the nearest viable block size for this * constraint. * * For example, if a block size of 1523 frames per pixel is * requested but the underlying model only supports value * summaries at powers-of-two block sizes, return 1024 or 2048 * depending on the rounding direction supplied. */ virtual size_t getNearestBlockSize(size_t requestedBlockSize, RoundingDirection = RoundNearest) const { if (requestedBlockSize > getMaxZoomLevel()) return getMaxZoomLevel(); else return requestedBlockSize; } /** * Return the maximum zoom level within range for this constraint. */ virtual size_t getMaxZoomLevel() const { return 262144; } }; #endif