Starting point for minimal Visual C++ X-Y Graph

Question

Is there a simple example of a program in Visual C++ that graphs x-y data?

This is to operate a small spectrometer. I would like a starting point that shows a graph and does little else, to which I will add controls, a thread that reads the data sent asynchronously from the instrument over a COM port and some plumbing to update the graph.

Thank you

Answer 1

A 'simple' plotting application is actually not all that simple. Also, if you make it as simple as possible, then adding bells and whistles is impossible without a re-write, so it becomes a dead end.

Anyway, this is what I use for developing windows applications that need to display a plot :

Sample plot application:

#include "wex.h"          //  https://github.com/JamesBremner/windex
#include "plot2d.h"

int main()
{
        wex::gui& fm = wex::maker::make();
        fm.move( {50,50,1200,600} );

        // construct plot to be drawn on form
        wex::plot::plot& thePlot = wex::maker::make<wex::plot::plot>(fm);
        thePlot.move( {30,30,1200,600});
        //thePlot.Grid( true );

        // resize plot when form resizes
        fm.events().resize([&](int w, int h )
        {
            thePlot.move( {30,30,w,h} );
            thePlot.update();
        });

        // construct plot traces
        wex::plot::trace& t1 = thePlot.AddStaticTrace();
        wex::plot::trace& t2 = thePlot.AddStaticTrace();

        // provide some data for first trace
        std::vector< double > d1 { 10, 15, 20, 25, 30, 25, 20, 15, 10 };
        t1.set( d1 );

        // plot in blue
        t1.color( 0x0000FF );

        // provide data for second trace
        std::vector< double > d2 { 20, 30, 40, 50, 60, 50, 40, 30, 20 };
        t2.set( d2 );

        // plot in red
        t2.color( 0xFF0000 );

        // show and run
        fm.show();
        fm.run();
}

By the way, there is no need to gather the data using a separate thread ( always a fruitful source of bugs ). Instead, use the windows API message pump, like this:

    wex::button &btnTime = wex::maker::make<wex::button>(fm);
    btnTime.move(300, 10, 100, 20);
    btnTime.text("Real Time");
    btnTime.tooltip("Display moving line plot that updates in real time");
    btnTime.events().click([&]
                           {
        // construct plot trace
        // displaying 100 points before they scroll off the plot
        plot::trace& t1 = thePlot.AddRealTimeTrace( 100 );

        // plot in blue
        t1.color( 0xFF0000 );

        // create timer handler to provide new data regularly
        fm.events().timer([&](int id)
        {
            static int p = 0;
            t1.add( 10 * sin( p++ / 10.0 ) );
            thePlot.update();
        });