view layer/LogColourScale.cpp @ 1605:ae2d5f8ff005

When asked to render the whole view width, we need to wait for the layers to be ready before we can determine what the width is
author Chris Cannam
date Thu, 30 Apr 2020 14:47:13 +0100
parents f2525e6cbdf1
children
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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 2006-2013 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 "LogColourScale.h"
#include "ColourScaleLayer.h"

#include "base/LogRange.h"

#include <QPainter>

#include <cmath>

#include "LayerGeometryProvider.h"

int
LogColourScale::getWidth(LayerGeometryProvider *,
                            QPainter &paint)
{
    // Qt 5.13 deprecates QFontMetrics::width(), but its suggested
    // replacement (horizontalAdvance) was only added in Qt 5.11
    // which is too new for us
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"

    return paint.fontMetrics().width("-000.00") + 15;
}

void
LogColourScale::paintVertical(LayerGeometryProvider *v,
                              const ColourScaleLayer *layer,
                              QPainter &paint,
                              int /* x0 */,
                              double minlog,
                              double maxlog)
{
    int h = v->getPaintHeight();

    int n = 10;

    double val = minlog;
    double inc = (maxlog - val) / n;

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

    int boxx = 5, boxy = 5;
    if (layer->getScaleUnits() != "") {
        boxy += paint.fontMetrics().height();
    }
    int boxw = 10, boxh = h - boxy - 5;

    int tx = 5 + boxx + boxw;
    paint.drawRect(boxx, boxy, boxw, boxh);

    paint.save();
    for (int y = 0; y < boxh; ++y) {
        double val = ((boxh - y) * (maxlog - minlog)) / boxh + minlog;
        paint.setPen(layer->getColourForValue(v, LogRange::unmap(val)));
        paint.drawLine(boxx + 1, y + boxy + 1, boxx + boxw, y + boxy + 1);
    }
    paint.restore();

    int dp = 0;
    if (inc > 0) {
        int prec = int(trunc(log10(inc)));
        prec -= 1;
        if (prec < 0) dp = -prec;
    }

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

        int y, ty;

        y = boxy + int(boxh - ((val - minlog) * boxh) / (maxlog - minlog));

        ty = y - paint.fontMetrics().height() +
            paint.fontMetrics().ascent() + 2;

        double dv = LogRange::unmap(val);
        int digits = int(trunc(log10(dv)));
        int sf = dp + (digits > 0 ? digits : 0);
        if (sf < 2) sf = 2;
        snprintf(buffer, buflen, "%.*g", sf, dv);

        QString label = QString(buffer);

        paint.drawLine(boxx + boxw - boxw/3, y, boxx + boxw, y);
        paint.drawText(tx, ty, label);

        val += inc;
    }
}