I would like to do a project that output value from Arduino and paint shapes in Qt. I am not sure if QCustomPlot can do this. Would you please give me some suggestion?
For example, I create a Qt GUI for entering the position(x,y) to Arduino and do calculation, then Arduino send the value signal to Qt and paint the shape on the position I want. Is it possible?
A few years ago, i do something like that using QWT and QextSerialPort. You have to connect your Arduino using a serial por (in Windows COM1, COM2...), and you will be able to read/write data from the buffer.
Now, Qt, integrates a native support for this task, check QtSerialPort Support, to configure your port check this class QSerialPort. How to read the data? Use QByteArray, an example:
QByteArray responseData = serial->readAll();
while(serial->waitForReadyRead(100))
responseData += serial->readAll();
Now store all the bytes in a QVector of type double.
QVector<double> data;
QDataStream stream(line);
stream >> data;
This data will be ploted by QCustomPlot. Example:
int numSamples = data.size();
QVector<double> x(numSamples), y(numSamples); // initialize with entries 0..100
for (int i=0; i<numSamples; ++i)
{
x[i] = i/50.0 - 1; // x goes from -1 to 1
y[i] = data[i]; // In this line copy the data from your Arduino Buffer and apply what you want, maybe some signal processing
}
// create graph and assign data to it:
customPlot->addGraph();
customPlot->graph(0)->setData(x, y);
// give the axes some labels:
customPlot->xAxis->setLabel("x");
customPlot->yAxis->setLabel("y");
// set axes ranges, so we see all data:
customPlot->xAxis->setRange(-1, 1);
customPlot->yAxis->setRange(0, 1);
customPlot->replot();
Enjoy!
