QtCS25 - High Performance Graphs & Painting

Session Summary

Session briefly presented performance benchmarks for 2D data in QtGraphs before moving onto presenting the new QCPainter, explaining the reasons behind it and showing demos and benchmarks.

Session Owners

Kaj Gränholm

Sakaria Pouke

Notes

QtGraphs 2D Performance:

For rapidly changing data, QtGraphs 2D is slow while QtGraphs 3D is fast.

QCPainter:

QRhi is high performance but hard to use. QPainter is easy to use but not high performance.

-> Enter QCPainter: Hardware accelerated C++ painting API.

Similar to QPainter but API is more compact

Thin layer on top of QRHI.

Talk discussed:

Currently implemented features

Methods for correct imperative painting

Performance benchmark demo

Benchmarks for Direct vs Path drawing (static and dynamic)

Canvas vs Compact Canvas performance

Next steps:

Get QCPainter into tech preview

Documentation, examples, demos

Use in QtGraphs