Demonstrates the speed and power of SciChart iOS for drawing real-time scientific waveforms in this iOS Oscilloscope Demo App.

The SCIFastLineRenderableSeries can be used to render a high performance iOS Line Chart in either Swift or Objective C. SciChart iOS supports millions of points out of the box, and is suitable for use in real-time scientific, medical and trading applications.

// OscilloscopeChartView.m

//******************************************************************************
// SCICHART® Copyright SciChart Ltd. 2011-2019. All rights reserved.
//
// Web: http://www.scichart.com
// Support: support@scichart.com
// Sales:   sales@scichart.com
//
// OscilloscopeChartView.m is part of the SCICHART® Examples. Permission is hereby granted
// to modify, create derivative works, distribute and publish any part of this source
// code whether for commercial, private or personal use.
//
// The SCICHART® examples are distributed in the hope that they will be useful, but
// without any warranty. It is provided "AS IS" without warranty of any kind, either
// expressed or implied.
//******************************************************************************

#import "OscilloscopeChartView.h"
#import "SCDDataManager.h"

static double const TimeInterval = 30.0;

@implementation OscilloscopeChartView {

    NSTimer *_timer;
    
    DataSourceEnum _selectedSource;
    
    SCIXyDataSeries *_dataSeries1;
    SCIXyDataSeries *_dataSeries2;
    
    SCIFastLineRenderableSeries *_rSeries;
    
    double _phase0;
    double _phase1;
    double _phaseIncrement;
    
    id<ISCIAxis> _xAxis;
    id<ISCIAxis> _yAxis;
}

- (void)initExample {
    _phaseIncrement = M_PI * 0.1;
    
    _xAxis = [SCINumericAxis new];
    _xAxis.autoRange = SCIAutoRange_Never;
    _xAxis.axisTitle = @"Time (ms)";
    _xAxis.visibleRange = [[SCIDoubleRange alloc] initWithMin:2.5 max:4.5];
    
    _yAxis = [SCINumericAxis new];
    _yAxis.autoRange = SCIAutoRange_Never;
    _yAxis.axisTitle = @"Voltage (mV)";
    _yAxis.visibleRange = [[SCIDoubleRange alloc] initWithMin:-12.5 max:12.5];
    
    _dataSeries1 = [[SCIXyDataSeries alloc] initWithXType:SCIDataType_Double yType:SCIDataType_Double];
    _dataSeries1.acceptsUnsortedData = YES;
    _dataSeries2 = [[SCIXyDataSeries alloc] initWithXType:SCIDataType_Double yType:SCIDataType_Double];
    _dataSeries2.acceptsUnsortedData = YES;
    
    _rSeries = [SCIFastLineRenderableSeries new];
    
    [self.surface.xAxes add:_xAxis];
    [self.surface.yAxes add:_yAxis];
    [self.surface.renderableSeries add:_rSeries];
    
    _timer = [NSTimer scheduledTimerWithTimeInterval:TimeInterval / 1000.0 target:self selector:@selector(updateOscilloscopeData:) userInfo:nil repeats:YES];
}

- (void)updateOscilloscopeData:(NSTimer *)timer {
    SCDDoubleSeries *doubleSeries = [SCDDoubleSeries new];
    if (_selectedSource == Lissajous) {
        [SCDDataManager setLissajousCurve:doubleSeries alpha:0.12 beta:_phase1 delta:_phase0 count:2500];
        [_dataSeries1 clear];
        [_dataSeries1 appendValuesX:doubleSeries.xValues y:doubleSeries.yValues];
        _rSeries.dataSeries = _dataSeries1;
    } else {
        [SCDDataManager setFourierSeries:doubleSeries amplitude:2.0 phaseShift:_phase0 count:1000];
        [_dataSeries2 clear];
        [_dataSeries2 appendValuesX:doubleSeries.xValues y:doubleSeries.yValues];
        _rSeries.dataSeries = _dataSeries2;
    }
    
    _phase0 += _phaseIncrement;
    _phase1 += _phaseIncrement * 0.005;
}

- (void)onFourierSeriesSelected {
    self->_selectedSource = FourierSeries;
    [self.surface.xAxes itemAt:0].visibleRange = [[SCIDoubleRange alloc] initWithMin:2.5 max:4.5];
    [self.surface.yAxes itemAt:0].visibleRange = [[SCIDoubleRange alloc] initWithMin:-12.5 max:12.5];
    self->_phaseIncrement = M_PI * 0.1;
}

- (void)onLissajousSelected {
    self->_selectedSource = Lissajous;
    [self.surface.xAxes itemAt:0].visibleRange = [[SCIDoubleRange alloc] initWithMin:-1.2 max:1.2];
    [self.surface.yAxes itemAt:0].visibleRange = [[SCIDoubleRange alloc] initWithMin:-1.2 max:1.2];
    self->_phaseIncrement = M_PI * 0.2;
}

- (void)onIsDigitalLineChanged:(BOOL)isDigitalLine {
    _rSeries.isDigitalLine = isDigitalLine;
}

- (void)viewDidDisappear:(BOOL)animated {
    [super viewDidDisappear:animated];
    
    [_timer invalidate];
    _timer = nil;
}

@end

// OscilloscopeChartView.swift

//******************************************************************************
// SCICHART® Copyright SciChart Ltd. 2011-2019. All rights reserved.
//
// Web: http://www.scichart.com
// Support: support@scichart.com
// Sales:   sales@scichart.com
//
// OscilloscopeChartView.swift is part of the SCICHART® Examples. Permission is hereby granted
// to modify, create derivative works, distribute and publish any part of this source
// code whether for commercial, private or personal use.
//
// The SCICHART® examples are distributed in the hope that they will be useful, but
// without any warranty. It is provided "AS IS" without warranty of any kind, either
// expressed or implied.
//******************************************************************************

enum DataSource {
    case Fourier
    case Lisajous
}

class OscilloscopeChartView: SCDOscilloscopeChartViewControllerBase {
    var _selectedSource: DataSource = .Fourier
    
    let _dataSeries1 = SCIXyDataSeries(xType: .double, yType: .double)
    let _dataSeries2 = SCIXyDataSeries(xType: .double, yType: .double)
    
    let _rSeries = SCIFastLineRenderableSeries()
    
    let _timeInterval = 30.0;
    var _timer: Timer!
    
    var _phase0 = 0.0
    var _phase1 = 0.0
    var _phaseIncrement = .pi * 0.1
    
    let _xAxis = SCINumericAxis()
    let _yAxis = SCINumericAxis()
    
    override func initExample() {
        _xAxis.autoRange = .never
        _xAxis.axisTitle = "Time (ms)"
        _xAxis.visibleRange = SCIDoubleRange(min: 2.5, max: 4.5)
        
        _yAxis.autoRange = .never
        _yAxis.axisTitle = "Voltage (mV)"
        _yAxis.visibleRange = SCIDoubleRange(min: -12.5, max: 12.5)

        _dataSeries1.acceptsUnsortedData = true
        _dataSeries2.acceptsUnsortedData = true
                
        surface.xAxes.add(_xAxis)
        surface.yAxes.add(_yAxis)
        surface.renderableSeries.add(_rSeries)
        
        _timer = Timer.scheduledTimer(timeInterval: _timeInterval / 1000.0, target: self, selector: #selector(updateOscilloscopeData), userInfo: nil, repeats: true)
    }
    
    @objc fileprivate func updateOscilloscopeData() {
        let doubleSeries = SCDDoubleSeries()
        if (_selectedSource == .Lisajous) {
            SCDDataManager.setLissajousCurve(doubleSeries, alpha: 0.12, beta: _phase1, delta: _phase0, count: 2500)
            _dataSeries1.clear()
            _dataSeries1.append(x: doubleSeries.xValues, y: doubleSeries.yValues)
            _rSeries.dataSeries = _dataSeries1
        } else {
            SCDDataManager.setFourierSeries(doubleSeries, amplitude: 2.0, phaseShift: _phase0, count: 1000)
            _dataSeries2.clear()
            _dataSeries2.append(x: doubleSeries.xValues, y: doubleSeries.yValues)
            _rSeries.dataSeries = _dataSeries2
        }
        
        _phase0 += _phaseIncrement
        _phase1 += _phaseIncrement * 0.005
    }
    
    override func onFourierSeriesSelected() {
        _selectedSource = .Fourier
        surface.xAxes[0].visibleRange = SCIDoubleRange(min: 2.5, max: 4.5)
        surface.yAxes[0].visibleRange = SCIDoubleRange(min: -12.5, max: 12.5)
        _phaseIncrement = .pi * 0.1
    }
    
    override func onLissajousSelected() {
        _selectedSource = .Lisajous
        surface.xAxes[0].visibleRange = SCIDoubleRange(min: -1.2, max: 1.2)
        surface.yAxes[0].visibleRange = SCIDoubleRange(min: -1.2, max: 1.2)
        _phaseIncrement = .pi * 0.2
    }
    
    override func onIsDigitalLineChanged(_ isDigitalLine: Bool) {
        _rSeries.isDigitalLine = isDigitalLine
    }
    
    override func viewDidDisappear(_ animated: Bool) {
        super.viewDidDisappear(animated)
        
        _timer.invalidate()
        _timer = nil
    }
}

// SCDOscilloscopeChartViewControllerBase.m

//******************************************************************************
// SCICHART® Copyright SciChart Ltd. 2011-2020. All rights reserved.
//
// Web: http://www.scichart.com
// Support: support@scichart.com
// Sales:   sales@scichart.com
//
// SCDOscilloscopeChartViewControllerBase.m is part of the SCICHART® Examples. Permission is hereby granted
// to modify, create derivative works, distribute and publish any part of this source
// code whether for commercial, private or personal use.
//
// The SCICHART® examples are distributed in the hope that they will be useful, but
// without any warranty. It is provided "AS IS" without warranty of any kind, either
// expressed or implied.
//******************************************************************************

#import "SCDOscilloscopeChartViewControllerBase.h"
#import "SCDSettingsPresenter.h"
#import "SCDToolbarButtonsGroup.h"
#import "SCDToolbarItem.h"
#import "SCDToolbarPopupItem.h"
#import "SCDLabeledSettingsItem.h"
#import "SCDSwitchItem.h"
#import "SCDConstants.h"

@implementation SCDOscilloscopeChartViewControllerBase {
    BOOL _isDigitalLine;
    NSArray<NSString *> *_seriesNames;
    NSInteger _initialSeriesIndex;
    NSArray<SCIAction> *_actions;
    SCDSettingsPresenter *_settingsPresenter;
}

- (Class)associatedType { return SCIChartSurface.class; }

- (BOOL)showDefaultModifiersInToolbar {
    return NO;
}

- (void)commonInit {
    __weak typeof(self) wSelf = self;
    
    _seriesNames = @[@"Fourier", @"Lisajous"];
    _actions = @[^{
        [wSelf onFourierSeriesSelected];
    }, ^{
        [wSelf onLissajousSelected];
    }];
    _isDigitalLine = NO;
    _initialSeriesIndex = 0;
}

- (NSArray<id<ISCDToolbarItem>> *)provideExampleSpecificToolbarItems {
    __weak typeof(self) wSelf = self;
    
    SCDToolbarButtonsGroup *settingsToolbar = [[SCDToolbarButtonsGroup alloc] initWithToolbarItems:@[
        [[SCDToolbarItem alloc] initWithTitle:@"Oscilloscope settings" image:[SCIImage imageNamed:@"chart.settings"] andAction:^{ [wSelf p_SCD_openSettings]; }]
    ]];
    settingsToolbar.identifier = TOOLBAR_MODIFIERS_SETTINGS;
    
    return @[settingsToolbar];
}

- (void)p_SCD_openSettings {
    _settingsPresenter = [[SCDSettingsPresenter alloc] initWithSettingsItems:[self p_SCD_createSettingsItems] andIdentifier:TOOLBAR_MODIFIERS_SETTINGS];
}

- (NSArray<id<ISCDToolbarItem>> *)p_SCD_createSettingsItems {
    __weak typeof(self) wSelf = self;
    SCDToolbarPopupItem *dataSourcePopupItem = [[SCDToolbarPopupItem alloc] initWithTitles:_seriesNames selectedIndex:_initialSeriesIndex andAction:^(NSUInteger selectedIndex) {
        self->_actions[selectedIndex]();
    }];
        
    return @[
        [[SCDLabeledSettingsItem alloc] initWithLabelText:@"Data source:" item:dataSourcePopupItem],
        [[SCDSwitchItem alloc] initWithTitle:@"Is step line" isSelected:_isDigitalLine andAction:^(BOOL isYLogAxis) {
            [wSelf p_SCD_changeIsDigital];
        }]
    ];
}

- (void)p_SCD_changeIsDigital {
    _isDigitalLine = !_isDigitalLine;
    
    [self onIsDigitalLineChanged:_isDigitalLine];
}

- (void)onFourierSeriesSelected { }
- (void)onLissajousSelected { }
- (void)onIsDigitalLineChanged:(BOOL)isDigitalLine { }

@end

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