view layer/LogNumericalScale.cpp @ 959:2633a1d73e39

Address #1214, layer import produces wrong layer type. We needed a more principled approach to making sure the format gets updated properly and the dialog elements are consistent (basically separating making the dialog elements consistent from subsequently updating the format). This change should provide that, though there may be gotchas still.

/* -*- 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 2006-2013 Chris Cannam and QMUL.
    
    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 "LogNumericalScale.h"
#include "VerticalScaleLayer.h"

#include "base/LogRange.h"

#include <QPainter>

#include <cmath>

#include "view/View.h"

//#define DEBUG_TIME_VALUE_LAYER 1

int
LogNumericalScale::getWidth(View *,
			    QPainter &paint)
{
    return paint.fontMetrics().width("-000.00") + 10;
}

void
LogNumericalScale::paintVertical(View *v,
				 const VerticalScaleLayer *layer,
				 QPainter &paint,
				 int x0,
				 double minlog,
				 double maxlog)
{
    int w = getWidth(v, paint) + x0;

    int n = 10;

    double val = minlog;
    double inc = (maxlog - val) / n; // even increments of log scale

    // smallest increment as displayed
    double minDispInc = LogRange::unmap(minlog + inc) - LogRange::unmap(minlog);

#ifdef DEBUG_TIME_VALUE_LAYER
    cerr << "min = " << minlog << ", max = " << maxlog << ", inc = " << inc << ", minDispInc = " << minDispInc << endl;
#endif

    const int buflen = 40;
    char buffer[buflen];

    double round = 1.f;
    int dp = 0;

    if (minDispInc > 0) {
        int prec = int(trunc(log10(minDispInc)));
        if (prec < 0) dp = -prec;
        round = pow(10.0, prec);
        if (dp > 4) dp = 4;
#ifdef DEBUG_TIME_VALUE_LAYER
        cerr << "round = " << round << ", prec = " << prec << ", dp = " << dp << endl;
#endif
    }

    int prevy = -1;
                
    for (int i = 0; i < n; ++i) {

	int y, ty;
        bool drawText = true;

	if (i == n-1 &&
	    v->height() < paint.fontMetrics().height() * (n*2)) {
	    if (layer->getScaleUnits() != "") drawText = false;
	}

        double dispval = LogRange::unmap(val);
	dispval = floor(dispval / round) * round;

#ifdef DEBUG_TIME_VALUE_LAYER
	cerr << "val = " << val << ", dispval = " << dispval << endl;
#endif

	y = layer->getYForValue(v, dispval);

	ty = y - paint.fontMetrics().height() + paint.fontMetrics().ascent() + 2;
	
	if (prevy >= 0 && (prevy - y) < paint.fontMetrics().height()) {
	    val += inc;
	    continue;
        }

	int digits = int(trunc(log10(dispval)));
	int sf = dp + (digits > 0 ? digits : 0);
	if (sf < 4) sf = 4;
#ifdef DEBUG_TIME_VALUE_LAYER
        cerr << "sf = " << sf << endl;
#endif
	snprintf(buffer, buflen, "%.*g", sf, dispval);

	QString label = QString(buffer);

	paint.drawLine(w - 5, y, w, y);

        if (drawText) {
	    paint.drawText(w - paint.fontMetrics().width(label) - 6,
			   ty, label);
        }

        prevy = y;
	val += inc;
    }
}