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// Copyright (C) 2023 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "datasource.h"
#include <QLabel>
#include <QRandomGenerator>
#include <QtMath>
#include <QXYSeries>
DataSource::DataSource(QObject *parent)
: QObject(parent)
{
generateData(0, 0, 0);
}
void DataSource::update(QAbstractSeries *series, int seriesIndex)
{
if (series) {
auto xySeries = static_cast<QXYSeries *>(series);
const QList<QList<QPointF>> &seriesData = m_data.at(seriesIndex);
if (seriesIndex == 0)
m_index++;
if (m_index > seriesData.count() - 1)
m_index = 0;
const auto points = seriesData.at(m_index);
// Use replace instead of clear + append, it's optimized for performance
xySeries->replace(points);
}
}
void DataSource::handleSceneChanged()
{
m_dataUpdater.start();
}
void DataSource::updateAllSeries()
{
static int frameCount = 0;
static QString labelText = QStringLiteral("FPS: %1");
for (int i = 0; i < m_seriesList.size(); i++)
update(m_seriesList[i], i);
frameCount++;
int elapsed = m_fpsTimer.elapsed();
if (elapsed >= 1000) {
elapsed = m_fpsTimer.restart();
qreal fps = qreal(0.1 * int(10000.0 * (qreal(frameCount) / qreal(elapsed))));
m_fpsLabel->setText(labelText.arg(QString::number(fps, 'f', 1)));
m_fpsLabel->adjustSize();
frameCount = 0;
}
}
void DataSource::startUpdates(const QList<QXYSeries *> &seriesList, QLabel *fpsLabel)
{
m_seriesList = seriesList;
m_fpsLabel = fpsLabel;
m_dataUpdater.setInterval(0);
m_dataUpdater.setSingleShot(true);
QObject::connect(&m_dataUpdater, &QTimer::timeout,
this, &DataSource::updateAllSeries);
m_fpsTimer.start();
updateAllSeries();
}
void DataSource::generateData(int seriesCount, int rowCount, int colCount)
{
m_data.clear();
qreal xAdjustment = 20.0 / (colCount * rowCount);
qreal yMultiplier = 3.0 / qreal(seriesCount);
// Append the new data depending on the type
for (int k(0); k < seriesCount; k++) {
QList<QList<QPointF>> seriesData;
qreal height = qreal(k) * (10.0 / qreal(seriesCount)) + 0.3;
for (int i(0); i < rowCount; i++) {
QList<QPointF> points;
points.reserve(colCount);
for (int j(0); j < colCount; j++) {
qreal x(0);
qreal y(0);
// data with sin + random component
y = height + (yMultiplier * qSin(M_PI / 50 * j)
+ (yMultiplier * QRandomGenerator::global()->generateDouble()));
// 0.000001 added to make values logaxis compatible
x = 0.000001 + 20.0 * (qreal(j) / qreal(colCount)) + (xAdjustment * qreal(i));
points.append(QPointF(x, y));
}
seriesData.append(points);
}
m_data.append(seriesData);
}
}