ChromaticityDotNet.OxyplotDiagram 1.0.4.12

ChromaticityDotNet.OxyplotDiagram

Framework-independent CIE xy and CIE 1976 u′v′ plots extracted from QuantumSpect. Depends on ChromaticityDotNet and OxyPlot.Core 2.2.0. No WPF, Avalonia, CommunityToolkit or application assembly is required.

using ChromaticityDotNet.Diagrams;
using ChromaticityDotNet.OxyplotDiagram;
using static ChromaticityDotNet.Model.DataModel;
using static ChromaticityDotNet.Model.StandardChromaticityModel.StandardilluminantClass;

var xy = new Cie1931Plot(StandardObserver.Degree10);
var uv = new Cie1976Plot(StandardObserver.Degree10);
var sample = new CIExyY { CIEx = 0.4, CIEy = 0.2, CIEY = 100 };
var data = WavelengthDiagramData.Create(sample, StandardObserver.Degree10, "D65");
xy.SetData(data);
uv.SetData(data);
// Bind each PlotModel and Controller to its platform-specific PlotView.

Cie1931Plot.UpdatePoint / UpdatePoints accept xyY. Cie1976Plot.UpdatePoint / UpdatePoints accept CIEuv (u′v′), not Luv* components. Both classes support UpdateXyPoints, SetObserver, ClearMeasurements and SetLightData. Create one instance per PlotView; models and mutable series are not shared.

Each measurement or observer update invalidates its host once, after the complete state is ready. Changes to series and ItemsSource request a data refresh, so WPF hosts do not need an extra PlotModel.InvalidatePlot(true) call. This also avoids drawing cleared markers and intermediate observer states during live acquisition.

The static series remain in QuantumSpect's original order: Planckian locus, then CIE boundary. Observer changes update both curves and the sRGB background and clear old measurements. Backgrounds are generated from the shared library data, without WPF pack URIs or application bitmap resources. BackgroundOpacity controls the background independently of curves and markers.

BackgroundColor defaults to white. Set it to the host surface color for a dark theme; the plot area, axes, labels, grid, and legend automatically use a readable palette.

xy.BackgroundColor = OxyPlot.OxyColor.FromRgb(32, 32, 32);

ShowWavelengthLabels controls edge wavelength captions (visible by default). ShowPlanckianLocus controls the curve and measurement connection to its nearest point (visible by default). ShowTemperatureLabels controls reference temperatures and the measured CCT label (hidden by default). Reference temperatures can appear independently of the curve. These settings survive observer and measurement updates. ShowLegend defaults to true; the blackbody curve and current measurement markers appear in the legend. Click an item to temporarily hide or restore it; hidden entries stay gray and selectable in the legend. Hidden targets are excluded from tracking. Hiding the blackbody curve also hides reference temperature labels and its nearest-point overlay, while the configured display options remain unchanged. Sample visibility resets when measurements are replaced; curve visibility persists until toggled back or explicitly assigned through ShowPlanckianLocus. ToggleLegendItem(index) also toggles an item in displayed legend order. Both plotting libraries place the legend inside the plot: xy at the top right, u′v′ at the bottom right. The shared default axes are xy 0–1.0 / 0–1.0 and u′v′ 0–0.8 / 0–0.7. AxisMaximumX / AxisMaximumY can expand these ranges for larger legends; null restores the defaults. Background image extents remain fixed in coordinate space. OxyPlot's Cartesian layout may extend the displayed ranges slightly to keep equal x/y scaling.

Bind Controller as well as PlotModel to the host PlotView. It explicitly maps the left mouse button to snap tracking; press and drag to inspect samples or curve vertices. Trackers display the name, xy / u′v′ coordinates, and wavelength / temperature / Duv where available. TrackerHitResult.Item contains the shared ChromaticityDiagramTarget with full-precision values. Measurement connectors are excluded from tracking so they do not hide marker data.

For example, a WPF view model can expose both properties from its chart instance:

<oxy:PlotView Model="{Binding PlotModel}" Controller="{Binding Controller}" />

Use SetSamples for named points on the background. Both plots accept the same xy samples and project them into their coordinate space; marker and legend colors match:

xy.ShowWavelengthLabels = false;
xy.ShowPlanckianLocus = false;
xy.ShowTemperatureLabels = false;
xy.SetSamples(new[]
{
    new ChromaticityDiagramSample("Reference", new ChromaticityCoordinates(0.3127, 0.3290), 0xFF2563EB),
    new ChromaticityDiagramSample("Sample 1", new ChromaticityCoordinates(0.4, 0.2), 0xFFE11D48)
});

SetSamples replaces previous measurement markers and labels. ClearMeasurements and observer changes clear the sample legend too. Existing unnamed UpdatePoints calls use Sample 1, Sample 2, etc. for multiple points.

The 10° Planckian locus is an observer-specific estimate. CCT / Duv are calculated in CIE 1960 UCS, then projected into the diagram; the drawn line length is not Duv.

Targets: netstandard2.0, net10.0. Code: MIT; CIE data: CC BY-SA 4.0.