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NativeImageRasterLayer

Namespace: ThinkGeo.Core

This class represents general image types to be drawn on the map, such as .BMP, .JPG, .PNG, etc.

public class NativeImageRasterLayer : RasterLayer

Inheritance ObjectLayerRasterLayerNativeImageRasterLayer

Remarks:

This type of layer is used to draw standard image types on the map. These include .BMP, .JPG, .PNG, .TIFF, and all other image types that are supported by the .NET Framework to be loaded as a Bitmap.

Each of these images will need a world file associated with it. The world file contains the geospatial information pertaining to the image. Using the world file, we know its spatial position and other required information to draw it on the map relative to other images or spatial features. World files are small text files with an extension that matches the original image's extension, but with the middle character of the extension changed to a "w". If you have images that you want to use but do not have their world files, please contact the source of the image so that they can provide one for you. world files are fairly common in the GIS community.

Properties

HasBoundingBox

This property checks to see if a Layer has a BoundingBox or not. If it has no BoundingBox, it will throw an exception when you call the GetBoundingBox() and GetFullExtent() APIs. In GdiPlusRasterLayer, we override this API and mark it as true.

public bool HasBoundingBox { get; }

Property Value

Boolean

Remarks:

The default implementation in the base class returns false.

ImagePathFilename

This property gets and sets the path and filename of the image file you want to use.

public string ImagePathFilename { get; set; }

Property Value

String
This property gets the path and filename of the image file you want to use.

Remarks:

This should be a complete path and filename for the image file.

ImageSource

This property gets and sets the Image used by the RasterLayer.

public RasterSource ImageSource { get; protected set; }

Property Value

RasterSource
This property gets the Image used by the RasterLayer.

Remarks:

The set for this property is protected and only intended to be used by developers who are creating their own ImageSources. This is the main property to set for developers who are creating their own RasterLayer derivatives.

UpperThreshold

This property gets and sets the upper threshold in the scale at which to display the image.

public double UpperThreshold { get; set; }

Property Value

Double
This property gets the upper threshold in the scale at which to display the image.

Remarks:

Above the upper threshold in scale, the image will not be displayed. This, in conjunction with the LowerThreshold property, allows you to create a band in which it is suitable to display the image source. By default, the upper threshold is double.max and lower threshold is double.min. This means the image should always display.

LowerThreshold

This property gets and sets the lower threshold in the scale at which to display the image.

public double LowerThreshold { get; set; }

Property Value

Double
This property gets the lower threshold in the scale at which to display the image.

Remarks:

Below the lower threshold in scale, the image will not be displayed. This, in conjunction with the UpperThreshold property, allows you to create a band in which it is suitable to display the image source. By default, the upper threshold is double.max and lower threshold is double.min. This means the image should always display.

ScaleFactor

The scale factor when drawing the primitive image. For example I am looking for an image with 100100px, If the ScaleFactor is set to 2, it means the component will get the image with 200200px. We want to keep it as 1 (by default) for most cases.

public double ScaleFactor { get; set; }

Property Value

Double

Projection

public Projection Projection { get; }

Property Value

Projection

IsOpen

This property returns true if the Layer is open and false if it is not.

public bool IsOpen { get; }

Property Value

Boolean

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.

DrawingTime

This property gets the last drawing time for the layer.

public TimeSpan DrawingTime { get; protected set; }

Property Value

TimeSpan

Remarks:

We track the drawing time for the layer and report it back in this method. This is useful for determining the speed of various layers.

Name

This property gets and sets the name for the layer.

public string Name { get; set; }

Property Value

String

Remarks:

The name is user defined. It is useful to set, as it may be used for higher level components such as legends, etc.

Attribution

public string Attribution { get; set; }

Property Value

String

IsVisible

This property gets and set the visible state of the layer.

public bool IsVisible { get; set; }

Property Value

Boolean

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.

Transparency

This property gets and sets the amount of transparency to apply to the image.

public float Transparency { get; set; }

Property Value

Single
This property gets the amount of transparency to apply to the image.

Remarks:

None

BlueTranslation

This property gets and sets the amount of blue to apply to the image.

public float BlueTranslation { get; set; }

Property Value

Single
This property gets the amount of blue to apply to the image.

Remarks:

None

RedTranslation

This property gets and sets the amount of red to apply to the image.

public float RedTranslation { get; set; }

Property Value

Single
This property gets the amount of red to apply to the image.

Remarks:

None

GreenTranslation

This property gets and sets the amount of green to apply to the image.

public float GreenTranslation { get; set; }

Property Value

Single
This property gets the amount of green to apply to the image.

Remarks:

None

KeyColors

Gets a value represents a collection of key colors. If SupportKeyColor property is false, it will throw exception when you use KeyColors.

public Collection<GeoColor> KeyColors { get; }

Property Value

Collection<GeoColor>

Remarks:

It will make these colors transparent when draw image.

IsNegative

This property gets and sets whether the image should be converted to negative (inverse colors).

public bool IsNegative { get; set; }

Property Value

Boolean
This property gets and sets whether the image should be converted to negative (inverse colors).

Remarks:

None

IsGrayscale

This property gets and sets if the image should be converted to grayscale.

public bool IsGrayscale { get; set; }

Property Value

Boolean

        This property gets and sets if the image should be converted to grayscale.

Remarks:

None

ColorMappings

ColorMapping

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

Property Value

Dictionary<GeoColor, GeoColor>

DrawingExceptionMode

Gets or sets the DrawExceptionMode when exception happens.

public DrawingExceptionMode DrawingExceptionMode { get; set; }

Property Value

DrawingExceptionMode

ThreadSafe

public ThreadSafetyLevel ThreadSafe { get; set; }

Property Value

ThreadSafetyLevel

Background

Gets and sets the background of the layer.

public GeoColor Background { get; set; }

Property Value

GeoColor

WrappingMode

public WrappingMode WrappingMode { get; set; }

Property Value

WrappingMode

WrappingExtent

public RectangleShape WrappingExtent { get; set; }

Property Value

RectangleShape

RequestDrawingInterval

public TimeSpan RequestDrawingInterval { get; set; }

Property Value

TimeSpan

Constructors

NativeImageRasterLayer()

This is a constructor for the class.

public NativeImageRasterLayer()

Remarks:

If you use this constructor, then you need to set the PathFilename property manually before using the layer.

NativeImageRasterLayer(String)

This is a constructor for the class.

public NativeImageRasterLayer(string imagePathFilename)

Parameters

imagePathFilename String
This parameter is the path and filename of the GDI+ image file you want to use. If you want to load a Tiff(.tif or .tiff) files, please use the GeoTiffRasterLayer instead for better performance.

Remarks:

This constructor gets the layer ready to use.

NativeImageRasterLayer(String, String)

This is a constructor for the class.

public NativeImageRasterLayer(string imagePathFilename, string worldfilePathFilename)

Parameters

imagePathFilename String
This parameter is the path and filename of the GDI+ image file you want to use. If you want to load a Tiff(.tif or .tiff) files, please use the GeoTiffRasterLayer instead for better performance.

worldfilePathFilename String
This parameter is the world file path and filename for the GDI+ image you want to use.

Remarks:

This constructor gets the layer ready to use.

NativeImageRasterLayer(String, RectangleShape)

This is a constructor for the class.

public NativeImageRasterLayer(string imagePathFilename, RectangleShape imageExtent)

Parameters

imagePathFilename String
This parameter is the path and filename of the GDI+ image file you want to use. If you want to load a Tiff(.tif or .tiff) files, please use the GeoTiffRasterLayer instead for better performance.

imageExtent RectangleShape
This parameter is the image extent of GDI+ image file you want to use.

Remarks:

This constructor gets the layer ready to use.

Events

StreamLoading

public event EventHandler<StreamLoadingEventArgs> StreamLoading;

DrawingProgressChanged

public event EventHandler<DrawingProgressChangedEventArgs> DrawingProgressChanged;

DrawingException

public event EventHandler<DrawingExceptionLayerEventArgs> DrawingException;

DrawnException

public event EventHandler<DrawnExceptionLayerEventArgs> DrawnException;

DrawingAttribution

public event EventHandler<DrawingAttributionLayerEventArgs> DrawingAttribution;

DrawnAttribution

public event EventHandler<DrawnAttributionLayerEventArgs> DrawnAttribution;

RequestedDrawing

public event EventHandler<RequestedDrawingLayerEventArgs> RequestedDrawing;

RequestingDrawing

public event EventHandler<RequestingDrawingLayerEventArgs> RequestingDrawing;