QCustomPlot Discussion and Comments

iRangeDrag is really slowReturn to overview

Hello,
On embedded linux platform i.mx 6ultralite Cortex-A7 Processor 696MHz(no OPENGL support) dragging graph with 2 points(1 line) is laggy to the point it just freezes and updates to last position.
Example: http://i.imgur.com/lmnZej4.gifv
It seems that repainting widget what causes the lag. How to optimize to have smooth dragging?

Have you read tips on this link :

http://www.qcustomplot.com/documentation/performanceimprovement.html

One thing that is mentioned :

To increase responsiveness during range dragging, consider setting QCustomPlot::setNoAntialiasingOnDrag to true. This is only relevant if using the default software renderer. (OpenGL antialiasing can't be toggled on-the-fly and would require an expensive reallocation of the sample buffer.)

Hope this can help !

Antialiasing is disabled for everything

ui->plot->setNotAntialiasedElements(QCP::aeAll);

I solved it by changing QPA plugin from DirectFB to XCB http://doc.qt.io/qt-5/embedded-linux.html. Dragging is still not super smooth but i found and older post how to implement frame skipping(great idea) http://www.qcustomplot.com/index.php/support/forum/868 which should make dragging performance even better.