view layer/ScrollableMagRangeCache.cpp @ 1135:628cd329c241 spectrogram-minor-refactor

Use a count of bins rather than min and max bins (because the name maxbin tells us nothing about whether the range is inclusive or not)
author Chris Cannam
date Wed, 03 Aug 2016 14:20:27 +0100
parents 745a868f0abf
children 9ff838a64461
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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 "ScrollableMagRangeCache.h"

#include <iostream>
using namespace std;

#define DEBUG_SCROLLABLE_MAG_RANGE_CACHE 1

void
ScrollableMagRangeCache::scrollTo(const LayerGeometryProvider *v,
				  sv_frame_t newStartFrame)
{	
    int dx = (v->getXForFrame(m_startFrame) -
	      v->getXForFrame(newStartFrame));

#ifdef DEBUG_SCROLLABLE_MAG_RANGE_CACHE
    cerr << "ScrollableMagRangeCache::scrollTo: start frame " << m_startFrame
	 << " -> " << newStartFrame << ", dx = " << dx << endl;
#endif

    if (m_startFrame == newStartFrame) {
	// haven't moved
        return;
    }
    
    m_startFrame = newStartFrame;

    if (dx == 0) {
	// haven't moved visibly (even though start frame may have changed)
	return;
    }
	
    int w = int(m_ranges.size());

    if (dx <= -w || dx >= w) {
	// scrolled entirely off
	invalidate();
	return;
    }
	
    // dx is in range, cache is scrollable

    if (dx < 0) {
	// The new start frame is to the left of the old start
	// frame. We need to add some empty ranges at the left (start)
	// end and clip the right end. Assemble -dx new values, then
	// w+dx old values starting at index 0.

	auto newRanges = vector<MagnitudeRange>(-dx);
	newRanges.insert(newRanges.end(),
			 m_ranges.begin(), m_ranges.begin() + (w + dx));
	m_ranges = newRanges;
	
    } else {
	// The new start frame is to the right of the old start
	// frame. We want to clip the left (start) end and add some
	// empty ranges at the right end. Assemble w-dx old values
	// starting at index dx, then dx new values.

	auto newRanges = vector<MagnitudeRange>(dx);
	newRanges.insert(newRanges.begin(),
			 m_ranges.begin() + dx, m_ranges.end());
	m_ranges = newRanges;
    }

//!!!    cerr << "maxes now: ";
//    for (int i = 0; in_range_for(m_ranges, i); ++i) {
//	cerr << m_ranges[i].getMax() << " ";
//    }
//    cerr << endl;
}

MagnitudeRange
ScrollableMagRangeCache::getRange(int x, int count) const
{
    MagnitudeRange r;
#ifdef DEBUG_SCROLLABLE_MAG_RANGE_CACHE
    cerr << "ScrollableMagRangeCache::getRange(" << x << ", " << count << ")" << endl;
#endif
    for (int i = 0; i < count; ++i) {
	r.sample(m_ranges.at(x + i));
    }
    return r;
}

void
ScrollableMagRangeCache::sampleColumn(int column, const MagnitudeRange &r)
{
    if (!in_range_for(m_ranges, column)) {
	cerr << "ERROR: ScrollableMagRangeCache::sampleColumn: column " << column
	     << " is out of range for cache of width " << m_ranges.size()
	     << " (with start frame " << m_startFrame << ")" << endl;
	throw logic_error("column out of range");
    } else {
	m_ranges[column].sample(r);
    }
}

//!!! unneeded?
void
ScrollableMagRangeCache::sampleColumn(const LayerGeometryProvider *v,
				      sv_frame_t frame,
				      const MagnitudeRange &r)
{
    int x = (v->getXForFrame(frame) -
	     v->getXForFrame(m_startFrame));

    if (!in_range_for(m_ranges, x)) {
	cerr << "WARNING: ScrollableMagRangeCache::sampleColumn: column " << x
	     << " arising from frame " << frame << " is out of range for cache "
	     << "of width " << m_ranges.size()
	     << " (with start frame " << m_startFrame << ")" << endl;
	throw logic_error("column out of range");
    } else {
	sampleColumn(x, r);
    }
}