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#include "verticalplotscale.h"
#include "ticksets/logarithmictickset.h"
#include "ticksets/numerictickset.h"
namespace {
const std::string kFontName = "Sans";
}
VerticalPlotScale::VerticalPlotScale()
: _plotWidth(0.0),
_plotHeight(0.0),
_fromTop(0.0),
_isSecondAxis(false),
_width(0.0),
_captionSize(0.0),
_metricsAreInitialized(false),
_alignTo(nullptr),
_tickSet(),
_axisType(AxisType::kNumeric),
_tickRange({0.0, 1.0}),
_isLogarithmic(false),
_drawWithDescription(true),
_unitsCaption("y"),
_descriptionFontSize(14),
_tickValuesFontSize(14) {}
VerticalPlotScale::~VerticalPlotScale() {}
double VerticalPlotScale::GetTickTextHeight(
const Cairo::RefPtr<Cairo::Context>& cairo) {
Pango::FontDescription fontDescription;
fontDescription.set_size(_tickValuesFontSize * PANGO_SCALE);
const Glib::RefPtr<Pango::Layout> layout = Pango::Layout::create(cairo);
layout->set_font_description(fontDescription);
layout->set_text("M");
return layout->get_pixel_logical_extents().get_height();
}
double VerticalPlotScale::UnitToAxis(double unitValue) const {
return _tickSet ? _tickSet->UnitToAxis(unitValue) : 0.0;
}
double VerticalPlotScale::AxisToUnit(double axisValue) const {
return _tickSet ? _tickSet->AxisToUnit(axisValue) : 0.0;
}
void VerticalPlotScale::Draw(const Cairo::RefPtr<Cairo::Context>& cairo,
double offsetX, double offsetY) {
offsetY += _fromTop;
initializeMetrics(cairo);
cairo->set_source_rgb(0.0, 0.0, 0.0);
const double x = _isSecondAxis ? offsetX : _width + offsetX;
const double tickX = _isSecondAxis ? 3 : -3;
const Glib::RefPtr<Pango::Layout> layout = Pango::Layout::create(cairo);
Pango::FontDescription fontDescription;
fontDescription.set_size(_tickValuesFontSize * PANGO_SCALE);
layout->set_font_description(fontDescription);
for (unsigned i = 0; i != _tickSet->Size(); ++i) {
const Tick tick = _tickSet->GetTick(i);
const double y = getTickYPosition(tick);
cairo->move_to(x + tickX, y + offsetY);
cairo->line_to(x, y + offsetY);
layout->set_text(tick.second);
const Pango::Rectangle extents = layout->get_pixel_logical_extents();
double textX;
if (_isSecondAxis)
textX = 8.0;
else
textX = -extents.get_width() - 8.0;
cairo->move_to(x + textX, y - extents.get_height() / 2 -
extents.get_ascent() + offsetY);
layout->show_in_cairo_context(cairo);
}
cairo->stroke();
if (_drawWithDescription) drawDescription(cairo, offsetX, offsetY);
}
void VerticalPlotScale::drawDescription(
const Cairo::RefPtr<Cairo::Context>& cairo, double offsetX,
double offsetY) {
cairo->save();
const Glib::RefPtr<Pango::Layout> layout = Pango::Layout::create(cairo);
Pango::FontDescription fontDescription;
fontDescription.set_size(_descriptionFontSize * PANGO_SCALE);
layout->set_font_description(fontDescription);
layout->set_text(_unitsCaption);
const Pango::Rectangle extents = layout->get_pixel_logical_extents();
const double x =
_isSecondAxis ? offsetX + 2 + _width - _captionSize : offsetX + 2;
cairo->translate(x - extents.get_ascent(), offsetY + 0.7 * _plotHeight);
cairo->rotate(M_PI * 1.5);
cairo->move_to(0.0, 0.0);
layout->show_in_cairo_context(cairo);
cairo->stroke();
cairo->restore();
// Base of arrow
cairo->move_to(x + extents.get_height() / 2.0, offsetY + _plotHeight * 0.9);
cairo->line_to(x + extents.get_height() / 2.0, offsetY + _plotHeight * 0.725);
cairo->stroke();
// The arrow
cairo->move_to(x + extents.get_height() / 2.0, offsetY + _plotHeight * 0.725);
cairo->line_to(x + 0.1 * extents.get_height(), offsetY + _plotHeight * 0.75);
cairo->line_to(x + 0.5 * extents.get_height(), offsetY + _plotHeight * 0.74);
cairo->line_to(x + 0.9 * extents.get_height(), offsetY + _plotHeight * 0.75);
cairo->close_path();
cairo->fill();
}
void VerticalPlotScale::initializeMetrics(
const Cairo::RefPtr<Cairo::Context>& cairo) {
if (!_metricsAreInitialized) {
if (_alignTo != nullptr) {
_alignTo->initializeMetrics(cairo);
_plotHeight = _alignTo->_plotHeight;
_fromTop = _alignTo->_fromTop;
}
if (_tickSet == nullptr) {
_width = 0.0;
} else {
_tickSet->Reset();
while (!ticksFit(cairo) && _tickSet->Size() > 2) {
_tickSet->DecreaseTicks();
}
const Glib::RefPtr<Pango::Layout> layout = Pango::Layout::create(cairo);
Pango::FontDescription fontDescription;
fontDescription.set_size(_tickValuesFontSize * PANGO_SCALE);
layout->set_font_description(fontDescription);
int maxWidth = 0;
for (unsigned i = 0; i != _tickSet->Size(); ++i) {
const Tick tick = _tickSet->GetTick(i);
layout->set_text(tick.second);
maxWidth =
std::max(maxWidth, layout->get_pixel_logical_extents().get_width());
}
_width = maxWidth + 10;
}
if (_drawWithDescription) {
const Glib::RefPtr<Pango::Layout> layout = Pango::Layout::create(cairo);
Pango::FontDescription fontDescription;
fontDescription.set_size(_descriptionFontSize * PANGO_SCALE);
layout->set_font_description(fontDescription);
layout->set_text(_unitsCaption);
_captionSize = layout->get_pixel_logical_extents().get_height();
_width += _captionSize;
} else {
_captionSize = 0.0;
}
_metricsAreInitialized = true;
}
}
void VerticalPlotScale::InitializeTicks() {
if (_isLogarithmic)
_tickSet.reset(new LogarithmicTickSet(_tickRange[0], _tickRange[1], 25));
else
_tickSet.reset(new NumericTickSet(_tickRange[0], _tickRange[1], 25));
_metricsAreInitialized = false;
}
double VerticalPlotScale::getTickYPosition(const Tick& tick) {
return (1.0 - tick.first) * _plotHeight;
}
bool VerticalPlotScale::ticksFit(const Cairo::RefPtr<Cairo::Context>& cairo) {
cairo->set_font_size(16.0);
double prevTopY = _plotHeight * 2.0;
for (unsigned i = 0; i != _tickSet->Size(); ++i) {
const Tick tick = _tickSet->GetTick(i);
Cairo::TextExtents extents;
cairo->get_text_extents(tick.second, extents);
// we want a distance of at least one x height between the text, hence
// height
const double bottomY = getTickYPosition(tick) + extents.height,
topY = bottomY - extents.height * 2;
if (bottomY > prevTopY) return false;
prevTopY = topY;
}
return true;
}
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