Qt OpenGL Widget as a view port for qcustomPlot

Qudor Eng

I'm working on project to plot the data from file. I use Qt5.4 and qcustomPlot library to plot the data as X,Y graph, as known the Qt5 don't support OpenGL. I google this problem and found this code:

QDeclarativeView mainwindow;
mainwindow.setSource(QUrl::fromLocalFile("./qml/app.qml"));
QGLFormat format = QGLFormat(QGL::DirectRendering); // you can play with other rendering formats like DoubleBuffer or SimpleBuffer
format.setSampleBuffers(false);
QGLWidget *glWidget = new QGLWidget(format);
glWidget->setAutoFillBackground(false);
mainwindow.setViewport(glWidget);

from this thread

but I'm new in Qt and C++ and do not know how to implment this code in my program. the source code of my program on GitHub in this link
please help me

SGaist

Hi,

Qt has support for OpenGL since way before Qt 5.

Changing the viewport is only available to a small subset of class which doesn't include QMainWindow.

Qudor Eng

@SGaist
thank you for replay. Do you suggest me to use QWT ? I think it support opengl

SGaist

I don't suggest anything since I don't know what you are trying to plot and why you would need OpenGL as a viewport for it.

Qudor Eng

@SGaist
I need to plot real-time signal and I want to use openGL because this plot will be run on raspberry pi "as known the pi CPU very very slow to plot real-time data"

tekojo

Hi, I moved the topic to "Mobile and Embedded" as it is about doing embedded.

SGaist

In that case you should rather look for a solution that can be power by OpenGL e.g. QtCharts

Qudor Eng

@SGaist
I think, I have to buy Qt licence to install QtCharts, isn't it?

SGaist

It will be available to both Commercial and GPLv3 since 5.6. See this article. So if your application is GPLv3 then your good to go.

Muzab

I am using Qt 5.6 Creator but

QT += charts

gives me an error:

Project ERROR: Unknown module(s) in QT: charts

vish

I have used qwt. It is coolest open source lib for chart, I would strongly recommend. Check it out if it meets your requirement.

SGaist

Because it's not part of Qt 5.6, you have to compile it by hand.

Muzab

The documentation here mentions that I can use Package Manager in Maintenance Tool. But for Qt Creator there is no option there to install add-ons. CAn you suggest me something?

SGaist

Again: currently it's not yet part of Qt's OpenSource offering so you have to clone it using git and built it by hand. The repository is here