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/*!
\example demos/qmloscilloscope
\title Oscilloscope
\image demos_qmloscilloscope.png
The oscilloscope application demonstrates how to use the Qt Charts QML API to implement an
application with strict performance requirements. The application uses generated data with
configurable characteristics to mimic a simple oscilloscope user interface. To find out the
actual screen refresh performance of the application, you can set QML_SHOW_FRAMERATE = 1 to
your run environment settings to get the framerate shown in the application output console.
To do so go to Projects - Run - Run environment in Qt Creator and select Add. Then you can
experiment with the different configurable options of the demo application to find the
configuration that gives you the best performance in your environment.
Note: You can try if enabling OpenGL improves the performance with the following startup
parameter:
\code
-graphicssystem opengl
\endcode
The application window is shared by control and scope views:
\snippet ../demos/qmloscilloscope/qml/qmloscilloscope/main.qml 1
\snippet ../demos/qmloscilloscope/qml/qmloscilloscope/main.qml 2
ControlView implements the buttons used for configuring. ScopeView uses a ChartView to show
a chart with two line series:
\snippet ../demos/qmloscilloscope/qml/qmloscilloscope/ScopeView.qml 1
The data of the line series is updated with a QML timer. In a real life application the
updating could be triggered with a signal from Qt C++ code.
\snippet ../demos/qmloscilloscope/qml/qmloscilloscope/ScopeView.qml 2
The oscilloscope also allows you to switch the type of the series used for visualizing the
signal sources. This is implemented by dynamically destroying and creating series:
\snippet ../demos/qmloscilloscope/qml/qmloscilloscope/ScopeView.qml 3
*/
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