+void SigView::setupViewport(int width, int height)
+{
+ glViewport(0, 0, (GLint)width, (GLint)height);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glOrtho(0, width, height, 0, -1, 1);
+ glMatrixMode(GL_MODELVIEW);
+}
+
+void SigView::paintRuler(QPainter &p)
+{
+ const double MinSpacing = 80;
+
+ const double min_period = _scale * MinSpacing;
+
+ const int order = (int)floorf(log10f(min_period));
+ const double order_decimal = pow(10, order);
+
+ int unit = 0;
+ double tick_period = 0.0f;
+
+ do
+ {
+ tick_period = order_decimal * ScaleUnits[unit++];
+ } while(tick_period < min_period && unit < countof(ScaleUnits));
+
+ const int prefix = (order - FirstSIPrefixPower) / 3;
+ assert(prefix >= 0);
+ assert(prefix < countof(SIPrefixes));
+
+ const int text_height = p.boundingRect(0, 0, INT_MAX, INT_MAX,
+ Qt::AlignLeft | Qt::AlignTop, "8").height();
+
+ // Draw the tick marks
+ p.setPen(Qt::black);
+
+ double t = ceil(_offset / tick_period) * tick_period;
+ double x = 0.0;
+ while((x = (t - _offset) / _scale + LabelMarginWidth) < width())
+ {
+ QString s;
+ QTextStream ts(&s);
+ ts << (t / order_decimal) << SIPrefixes[prefix] << "s";
+ p.drawText(x, 0, 0, text_height, Qt::AlignCenter | Qt::AlignTop |
+ Qt::TextDontClip, s);
+ p.drawLine(x, text_height, x, RulerHeight);
+ t += tick_period;
+ }
+}