Skip to content

MagneticDeclinationPrinterLayoutAsyncLayer

Namespace: ThinkGeo.Core

A layout layer that draws a magnetic declination diagram (true north, grid north, and magnetic north lines) computed from the IGRF model for the map inside the layout.

public class MagneticDeclinationPrinterLayoutAsyncLayer : PrinterLayoutAsyncLayer

Inheritance object → LayerBase → AsyncLayer → PrinterLayoutAsyncLayer → MagneticDeclinationPrinterLayoutAsyncLayer

Properties

SampleDateTime

Gets or sets the date the declination is sampled for (magnetic declination drifts over time).

public DateTime SampleDateTime { get; set; }

Property Value

DateTime

Elevation

Gets or sets the elevation, in MagneticDeclinationPrinterLayoutAsyncLayer.ElevationUnit, used when computing the declination.

public double Elevation { get; set; }

Property Value

double

MagneticFieldPathFilename

Gets the path to the IGRF magnetic field model file, or null/empty when the built-in model is used. After opening, this may hold the alternate stream name supplied via the MagneticDeclinationPrinterLayoutAsyncLayer.StreamLoading event, which need not be a file path.

public string MagneticFieldPathFilename { get; }

Property Value

string

MapLayer

Gets or sets the map layout layer whose center location the declination is computed for.

public MapPrinterLayoutAsyncLayer MapLayer { get; set; }

Property Value

MapPrinterLayoutAsyncLayer

GridNorthLineStyle

Gets or sets the line style used to draw the grid north line.

public LineStyle GridNorthLineStyle { get; set; }

Property Value

LineStyle

TrueNorthLineStyle

Gets or sets the line style used to draw the true north line.

public LineStyle TrueNorthLineStyle { get; set; }

Property Value

LineStyle

MagneticNorthLineStyle

Gets or sets the line style used to draw the magnetic north line.

public LineStyle MagneticNorthLineStyle { get; set; }

Property Value

LineStyle

TextStyle

Gets or sets the text style used to draw the diagram's labels and declination angles.

public TextStyle TextStyle { get; set; }

Property Value

TextStyle

TrueNorthPointStyle

Gets or sets the point style used to draw the true north star marker.

public PointStyle TrueNorthPointStyle { get; set; }

Property Value

PointStyle

ElevationUnit

Gets or sets the unit that MagneticDeclinationPrinterLayoutAsyncLayer.Elevation is expressed in.

public DistanceUnit ElevationUnit { get; set; }

Property Value

DistanceUnit

HasBoundingBox

Gets a value indicating that printer layers always expose a bounding box.

public bool HasBoundingBox { get; }

Property Value

bool

BackgroundMask

Gets or sets the fill and outline mask drawn beneath the layer content.

public AreaStyle BackgroundMask { get; set; }

Property Value

AreaStyle

ResizeMode

Gets or sets how the layer responds to resize operations.

public PrinterResizeMode ResizeMode { get; set; }

Property Value

PrinterResizeMode

DragMode

Gets or sets how the layer responds to drag operations in the layout designer.

public PrinterDragMode DragMode { get; set; }

Property Value

PrinterDragMode

IsResizing

Gets or sets a value indicating whether the layer is currently being resized.

public bool IsResizing { get; set; }

Property Value

bool

SelectabilityMode

Gets or sets whether the layer can be selected in the layout designer.

public PrinterLayerSelectabilityMode SelectabilityMode { get; set; }

Property Value

PrinterLayerSelectabilityMode

Name

Gets or sets the display name for the layer.

public string Name { get; set; }

Property Value

string
The name used to identify the layer within UI components such as legends.

Remarks:

The name is user defined. Assign a descriptive value so tooling such as legends and layer lists can surface a meaningful label to end users.

IsOpen

Gets a value indicating whether the layer is currently open.

public bool IsOpen { get; }

Property Value

bool
true if the layer has completed its open routine; otherwise, false.

Remarks:

This method is the concrete wrapper for the abstract method IsOpenCore. Various methods on the Layer require that it be in an open state. If one of those methods is called when the state is not open, then the method will throw an exception. To enter the open state, you must call the Layer Open method. The method will raise an exception if the current Layer is already open.

As this is a concrete public method that wraps a Core method, we reserve the right to add events and other logic to pre- or post-process data returned by the Core version of the method. In this way, we leave our framework open on our end, but also allow you the developer to extend our logic to suit your needs. If you have questions about this, please contact our support team as we would be happy to work with you on extending our framework.

IsVisible

Gets or sets a value indicating whether the layer is visible.

public bool IsVisible { get; set; }

Property Value

bool
true to draw the layer; otherwise, false.

Remarks:

If this property is set to false, the layer will not draw. We ensure this in the Draw method. This is useful for legends and other controls that control the visibility of layers.

Projection

Gets the projection of the layer.

public Projection Projection { get; set; }

Property Value

Projection

DrawingExceptionMode

Gets or sets how drawing exceptions are handled when the layer renders.

public DrawingExceptionMode DrawingExceptionMode { get; set; }

Property Value

DrawingExceptionMode

Background

Gets or sets the background color used when rendering the layer.

public GeoColor Background { get; set; }

Property Value

GeoColor
The fill applied to areas not covered by layer content.

Transparency

Gets or sets the amount of transparency applied to the rendered image.

public float Transparency { get; set; }

Property Value

float
A value between 0 (fully transparent) and 255 (fully opaque).

Opacity

Gets or sets the opacity applied to the rendered image.

public float Opacity { get; set; }

Property Value

float
A value between 0.0 (fully transparent) and 1.0 (fully opaque).

BlueTranslation

Gets or sets the intensity adjustment applied to the blue channel.

public float BlueTranslation { get; set; }

Property Value

float
A value between -255 and 255 representing the blue channel translation.

RedTranslation

Gets or sets the intensity adjustment applied to the red channel.

public float RedTranslation { get; set; }

Property Value

float
A value between -255 and 255 representing the red channel translation.

GreenTranslation

Gets or sets the intensity adjustment applied to the green channel.

public float GreenTranslation { get; set; }

Property Value

float
A value between -255 and 255 representing the green channel translation.

KeyColors

Gets the collection of key colors that should be rendered as transparent.

public Collection<GeoColor> KeyColors { get; }

Property Value

Collection<GeoColor>

Remarks:

Attempting to access this collection when the associated GeoCanvas does not support key colors (see GeoCanvas.SupportKeyColor) results in an exception. Add colors to this collection to ensure they render as transparent.

IsNegative

Gets or sets a value indicating whether the image should be rendered with inverted colors.

public bool IsNegative { get; set; }

Property Value

bool
true to invert the color channels; otherwise, false.

IsGrayscale

Gets or sets a value indicating whether the image should be converted to grayscale prior to rendering.

public bool IsGrayscale { get; set; }

Property Value

bool
true to apply a grayscale filter; otherwise, false.

ConcurrentAccess

Gets or sets how this layer behaves when more than one thread wants to draw it at once, and what a caller who wants concurrency should therefore do with it.

public ConcurrentAccess ConcurrentAccess { get; set; }

Property Value

ConcurrentAccess
unless the layer says otherwise: callers take turns on the one instance, which is what the screen renderer has done with a layer that did not say otherwise since this question was first asked.

Remarks:

A FeatureLayer that is not given a value of its own answers with its FeatureLayer.FeatureSource's, so a layer and the source it reads through cannot disagree about this.

ThreadSafe

Gets or sets the threading guarantees provided by the layer implementation.

public ThreadSafetyLevel ThreadSafe { get; set; }

Property Value

ThreadSafetyLevel
The level of thread safety that callers can expect when interacting with the layer.

Remarks:

Replaced by LayerBase.ConcurrentAccess and kept only so that code written against it is told, by name, what to use instead. It does not compile, so there is never a question of which of the two a caller meant: there is one value, and it is the other one. That matters because the translation was lossy in one direction - writing ThreadSafetyLevel.Unsafe could only pick ConcurrentAccess.UnsafeLock, and would silently undo a layer or source that had said ConcurrentAccess.UnsafeClone.

ColorMappings

Gets the color translation map that will be applied when rendering the layer.

public Dictionary<GeoColor, GeoColor> ColorMappings { get; }

Property Value

Dictionary<GeoColor, GeoColor>

WrappingMode

Gets or sets how the layer wraps when the map extent crosses world boundaries.

public WrappingMode WrappingMode { get; set; }

Property Value

WrappingMode

WrappingExtent

Gets or sets the geographic extent to use when wrapping is enabled.

public RectangleShape WrappingExtent { get; set; }

Property Value

RectangleShape

Constructors

MagneticDeclinationPrinterLayoutAsyncLayer()

Initializes a new instance of the MagneticDeclinationPrinterLayoutAsyncLayer class with no map layer, using the built-in IGRF model.

public MagneticDeclinationPrinterLayoutAsyncLayer()

MagneticDeclinationPrinterLayoutAsyncLayer(MapPrinterLayoutAsyncLayer)

Initializes a new instance of the MagneticDeclinationPrinterLayoutAsyncLayer class for the specified map layer, using the built-in IGRF model.

public MagneticDeclinationPrinterLayoutAsyncLayer(MapPrinterLayoutAsyncLayer mapLayer)

Parameters

mapLayer MapPrinterLayoutAsyncLayer
The map layout layer whose center location the declination is computed for.

MagneticDeclinationPrinterLayoutAsyncLayer(string, MapPrinterLayoutAsyncLayer)

Initializes a new instance of the MagneticDeclinationPrinterLayoutAsyncLayer class with a magnetic field model file and map layer.

public MagneticDeclinationPrinterLayoutAsyncLayer(string magneticFieldPathFilename, MapPrinterLayoutAsyncLayer mapLayer)

Parameters

magneticFieldPathFilename string
The path to the IGRF magnetic field model file; pass empty to use the built-in model.

mapLayer MapPrinterLayoutAsyncLayer
The map layout layer whose center location the declination is computed for.

Methods

OnStreamLoading(StreamLoadingEventArgs)

This method allows you to raise the StreamLoading event.

protected void OnStreamLoading(StreamLoadingEventArgs e)

Parameters

e StreamLoadingEventArgs

        This parameter represents the event arguments you want to raise the StreamLoading
        event with.

Returns

void
None

Remarks:

This method allows you to raise the StreamLoading event. Normally events are not accessible to derived classes, so we exposed a way to raise the event as necessary through this protected method.

OpenAsyncCore(CancellationToken)

protected Task OpenAsyncCore(CancellationToken cancellationToken)

Parameters

cancellationToken CancellationToken

Returns

Task

CloseAsyncCore(CancellationToken)

protected Task CloseAsyncCore(CancellationToken cancellationToken)

Parameters

cancellationToken CancellationToken

Returns

Task

SetPositionCore(double, double, double, double, PrintingUnit)

protected RectangleShape SetPositionCore(double width, double height, double centerPointX, double centerPointY, PrintingUnit unit)

Parameters

width double

height double

centerPointX double

centerPointY double

unit PrintingUnit

Returns

RectangleShape

DrawAsyncCore(GeoCanvas, Collection<SimpleCandidate>)

protected Task DrawAsyncCore(GeoCanvas canvas, Collection<SimpleCandidate> labelsInAllLayers)

Parameters

canvas GeoCanvas

labelsInAllLayers Collection<SimpleCandidate>

Returns

Task

Events

StreamLoading

This event allows you to pass in your own stream to represent the image.

public event EventHandler<StreamLoadingEventArgs> StreamLoading;

DrawingException

Occurs when the DrawingException event is raised.

public event EventHandler<DrawingExceptionLayerEventArgs> DrawingException;

DrawnException

Occurs when the DrawnException event is raised.

public event EventHandler<DrawnExceptionLayerEventArgs> DrawnException;