comparison layer/LogColourScale.cpp @ 699:1a1448f7beb2

Pull out colour scale drawing as well

+/* -*- 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 "view/View.h"
+
+int
+LogColourScale::getWidth(View *v,
+			    QPainter &paint)
+{
+    return paint.fontMetrics().width("-000.00") + 15;
+}
+
+void
+LogColourScale::paintVertical(View *v,
+			      const ColourScaleLayer *layer,
+			      QPainter &paint,
+			      int x0,
+			      float minlog,
+			      float maxlog)
+{
+    int h = v->height();
+
+    int n = 10;
+
+    float val = minlog;
+    float inc = (maxlog - val) / n;
+
+    char buffer[40];
+
+    int w = getWidth(v, paint) + x0;
+
+    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) {
+	float 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 = trunc(log10f(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 = trunc(log10f(dv));
+	int sf = dp + (digits > 0 ? digits : 0);
+	if (sf < 2) sf = 2;
+	sprintf(buffer, "%.*g", sf, dv);
+
+	QString label = QString(buffer);
+
+	paint.drawLine(boxx + boxw - boxw/3, y, boxx + boxw, y);
+	paint.drawText(tx, ty, label);
+
+	val += inc;
+    }
+}