data oscilloscope

DataOscilloscope

#example #data #drawing #settings #control #graphics

Scrolling waveform display with custom drawing.

Module Name	data oscilloscope example
Type	mtControl
Color	clInterfaceDesignModuleColor
Source	examples/DataOscilloscope/

Description

A visual oscilloscope that displays incoming data as a scrolling waveform. Demonstrates custom drawing with the path API, settings panels, and contextual menus.

Parameters

#	Name	Type	I/O	Range	Scale	Default	Callback
0	y	ptDataField	Input	-1 to 1	Linear	0.5	ctImmediate
1	speed	ptDataFader	Input	0 to 0.5	scLog	0.005	ctNormal
2	color	ptColor	Input	—	—	—	ctImmediate

How It Works

1. onCallBack: Stores incoming y value, speed offset, and color using std::atomic for thread safety
2. onProcess: On sdkRefreshSpeedClock() tick, calls advance() which:
   • Adds a new point at x=0 with current y value
   • Shifts all existing points to the right by the speed offset
   • Removes points that have scrolled past x=1.0
   • Calls sdkRepaintPanel() to trigger redraw
3. onPaint: Draws a smooth path through all stored points using the path drawing API

Key Concepts Demonstrated

• mtControl module type with custom canvas
• Path drawing API: sdkDrawPathStart(), sdkDrawPathMoveTo(), sdkDrawPathLineTo(), sdkDrawPathClose(), sdkDrawPathDraw()
• sdkRefreshSpeedClock() for frame-rate-aware animation updates
• Settings panel: sdkAddSettingLineColor() for persistent color settings
• Contextual menu: onCreateCommands() for right-click actions
• std::atomic for safe data sharing between audio and GUI threads

SDK Callbacks Used

onGetModuleInfo · onInitModule · onGetParamInfo · onCallBack · onProcess · onCreateSettings · onSettingsHasChanged · onCreateCommands · onPaint

Related Examples

• DataSampler — Data recording with visualization
• DrawBox — Simpler custom drawing
• DrawTrajectoryBox — Advanced path drawing

SDK Reference

• UserModuleBase Class
• UserModuleBase Drawing Methods