metavis/metavis/CustomLineGraph.cpp

#include "CustomLineGraph.h"

#include <QDebug>
#include <QBrush>
#include <random>
#include <algorithm>

CustomLineGraph::CustomLineGraph(QWidget* parent):QWidget(parent), linePen(Qt::blue), rectPen(Qt::red), axisPen(Qt::black)
{
	linePen.setWidth(3);
	linePen.setJoinStyle(Qt::PenJoinStyle::RoundJoin);
	LineGraphSeries lgs;
	//Populate data with DummyData
	//Draw Points
	std::random_device rd;  //Will be used to obtain a seed for the random number engine
	std::mt19937 gen(rd()); //Standard mersenne_twister_engine seeded with rd()
	std::uniform_int_distribution<> dis(-3, 3);
	for (int randomSeries = 0; randomSeries < 2; randomSeries++) {
		for (int i = 0; i < 21; i++) {
			QPoint point(i * 50 + 500,i * 1 + dis(gen) - 10000);
			lgs.data.push_back(point);
		}

		auto pairX = std::minmax_element(std::begin(lgs.data), std::end(lgs.data), [](const QPoint& a,const QPoint& b) -> bool {return a.x() < b.x(); });
		lgs.minX = pairX.first->x();
		lgs.maxX = pairX.second->x();
		auto pairY = std::minmax_element(std::begin(lgs.data), std::end(lgs.data), [](const QPoint& a, const QPoint& b) -> bool {return a.y() < b.y(); });
		lgs.minY = pairY.first->y();
		lgs.maxY = pairY.second->y();
		lgs.rangeX = std::abs(lgs.maxX - lgs.minX);
		lgs.rangeY = std::abs(lgs.maxY - lgs.minY);
		seriesVec.push_back(lgs);
	}
}

CustomLineGraph::~CustomLineGraph()
{
}
void CustomLineGraph::paintEvent(QPaintEvent* event)
{
	QPainter painter(this);
	painter.setRenderHint(QPainter::RenderHint::HighQualityAntialiasing);
	
	//Calculate LineRect
	QRect lineRect(rect());
	lineRect.setBottom(lineRect.bottom() - 20);
	lineRect.setLeft(lineRect.left() + 40);
	lineRect.setTop(lineRect.top() + 20);
	lineRect.setRight(lineRect.right() - 10);
	lineRect.setWidth(lineRect.width() - (lineRect.width() % 10) + 1);
	lineRect.setHeight(lineRect.height() - (lineRect.height() % 10) + 1);


	//draw Title
	painter.setPen(axisPen);
	painter.setFont(QFont("Arial", 12));
	QRect titleRect(QPoint(lineRect.left(), rect().top()), QPoint(lineRect.right(), lineRect.top()));
	painter.drawText(titleRect, Qt::AlignCenter, "title");


	//draw X-Axis
	QRect xAxisRect(QPoint(lineRect.left(), lineRect.bottom()), QPoint(lineRect.right(), rect().bottom()));
	QPainterPath xAxisPath;
	xAxisPath.moveTo(xAxisRect.left(), xAxisRect.top());
	xAxisPath.lineTo(xAxisRect.right(), xAxisRect.top());
	int xGap = xAxisRect.width() / 10;
	for (int i = 0; i < 11; i++) {
		xAxisPath.moveTo(xAxisRect.left() + i * xGap, xAxisRect.top() + 5);
		xAxisPath.lineTo(xAxisRect.left() + i * xGap, xAxisRect.top());
	}
	painter.drawPath(xAxisPath);

	//draw Y-Axis
	QRect yAxisRect(QPoint(rect().left(), lineRect.top()), QPoint(lineRect.left(), lineRect.bottom()));
	QPainterPath yAxisPath;
	yAxisPath.moveTo(yAxisRect.right(), yAxisRect.bottom() + 5);
	yAxisPath.lineTo(yAxisRect.right(), yAxisRect.top());
	int yGap = yAxisRect.height() / 10;
	for (int i = 0; i < 11; i++) {
		yAxisPath.moveTo(yAxisRect.right() - 5, yAxisRect.top() + i * yGap);
		yAxisPath.lineTo(yAxisRect.right(), yAxisRect.top() + i * yGap);
	}
	painter.drawPath(yAxisPath);



	
	

	painter.setPen(linePen);
	for (LineGraphSeries series : seriesVec) {

		double stregth_factorX = lineRect.width() / series.rangeX;
		double stregth_factorY = lineRect.height() / series.rangeY;
		QPointF translation(lineRect.left(), lineRect.top());
		QPainterPath painterPath;
		painterPath.moveTo(transformPoint(series.data[0], series, stregth_factorX, stregth_factorY));
		for(int i = 1; i < seriesVec[0].data.size(); i++) {
			painterPath.lineTo(transformPoint(series.data[i], series, stregth_factorX, stregth_factorY));
		}
		painterPath.translate(translation);
		painter.drawPath(painterPath);
		int radius;
		for (int i = 0; i < seriesVec[0].data.size(); i++) {
			painter.drawEllipse(transformPoint(series.data[i], series, stregth_factorX, stregth_factorY) + translation, 3, 3);
		}
	}
	
}

QPoint CustomLineGraph::transformPoint(QPoint& point, LineGraphSeries& lgs, double stregth_factorX, double stregth_factorY)
{
	return QPoint((point.x() - lgs.minX)* stregth_factorX , (lgs.maxY - point.y()) * stregth_factorY);
}