RasterXyzTileAsyncLayer¶
Namespace: ThinkGeo.Core
public abstract class RasterXyzTileAsyncLayer : XyzTilesAsyncLayer
Inheritance Object → LayerBase → AsyncLayer → XyzTilesAsyncLayer → RasterXyzTileAsyncLayer
Properties¶
RenderBeyondMaxZoom¶
public bool RenderBeyondMaxZoom { get; set; }
Property Value¶
TileCache¶
public RasterTileCache TileCache { get; set; }
Property Value¶
ProjectedTileCache¶
public RasterTileCache ProjectedTileCache { get; set; }
Property Value¶
ProjectionConverter¶
public ProjectionConverter ProjectionConverter { get; set; }
Property Value¶
IsCacheOnly¶
public bool IsCacheOnly { get; set; }
Property Value¶
MaxZoomOfTheData¶
public int MaxZoomOfTheData { get; set; }
Property Value¶
TileWidth¶
public int TileWidth { get; set; }
Property Value¶
TileHeight¶
public int TileHeight { get; set; }
Property Value¶
MaxExtent¶
This is the full extent of the matrix griding the xyz tiles. It's NOT the bounding box of the data itself.
public RectangleShape MaxExtent { get; set; }
Property Value¶
MapUnit¶
public GeographyUnit MapUnit { get; set; }
Property Value¶
HasBoundingBox¶
public bool HasBoundingBox { get; }
Property Value¶
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 0. 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 0. This means the image should always display.
UpperScale¶
This property gets and sets the upper threshold in the scale at which to display the image.
public double UpperScale { 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 0. This means the image should always display.
LowerScale¶
This property gets and sets the lower threshold in the scale at which to display the image.
public double LowerScale { 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 0. This means the image should always display.
Name¶
This property gets and sets the name for the layer.
public string Name { get; set; }
Property Value¶
Remarks:
The name is user defined. It is useful to set, as it may be used for higher level components such as legends, etc.
IsOpen¶
This property returns true if the Layer is open and false if it is not.
public bool IsOpen { get; }
Property Value¶
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¶
This property gets and set the visible state of the layer.
public bool IsVisible { get; set; }
Property Value¶
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.
DrawingTime¶
This property gets the last drawing time for the layer.
public TimeSpan DrawingTime { get; protected set; }
Property Value¶
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.
Projection¶
Gets the projection of the layer.
public Projection Projection { get; set; }
Property Value¶
DrawingExceptionMode¶
public DrawingExceptionMode DrawingExceptionMode { get; set; }
Property Value¶
Background¶
Gets and sets the background of the layer.
public GeoColor Background { get; set; }
Property Value¶
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¶
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¶
This property gets and sets if the image should be converted to grayscale.
Remarks:
None
ThreadSafe¶
public ThreadSafetyLevel ThreadSafe { get; set; }
Property Value¶
ColorMappings¶
ColorMapping
public Dictionary<GeoColor, GeoColor> ColorMappings { get; }
Property Value¶
Dictionary<GeoColor, GeoColor>
WrappingMode¶
public WrappingMode WrappingMode { get; set; }
Property Value¶
WrappingExtent¶
public RectangleShape WrappingExtent { get; set; }
Property Value¶
Methods¶
GetBoundingBoxCore()¶
protected RectangleShape GetBoundingBoxCore()
Returns¶
OpenAsyncCore(CancellationToken)¶
protected Task OpenAsyncCore(CancellationToken cancellationToken)
Parameters¶
cancellationToken CancellationToken
Returns¶
CloseAsyncCore(CancellationToken)¶
protected Task CloseAsyncCore(CancellationToken cancellationToken)
Parameters¶
cancellationToken CancellationToken
Returns¶
GetTileScaleCore()¶
protected int GetTileScaleCore()
Returns¶
DrawAsyncCore(GeoCanvas, Collection<SimpleCandidate>)¶
protected Task DrawAsyncCore(GeoCanvas canvas, Collection<SimpleCandidate> labelsInAllLayers)
Parameters¶
canvas GeoCanvas
labelsInAllLayers Collection<SimpleCandidate>
Returns¶
GenerateTileCacheAsync(RectangleShape, Int32, Int32, Single, OverwriteMode, CancellationToken)¶
Asynchronously generates and caches tiles for a given extent across the specified zoom levels.
public Task GenerateTileCacheAsync(RectangleShape extent, int startZoom, int endZoom, float scaleFactor, OverwriteMode overwriteMode, CancellationToken cancellationToken)
Parameters¶
extent RectangleShape
The geographic area (in map coordinates) to generate tiles for.
startZoom Int32
The starting zoom level for which tiles should be generated.
endZoom Int32
The ending zoom level (inclusive) for which tiles should be generated.
scaleFactor Single
An optional scale multiplier to apply to each tile during generation. For example if the tile size is 256*256, the cached tile would be 512 * 512 if it's 2.0. It defaults to 1.0 (no scaling).
overwriteMode OverwriteMode
Specifies whether to overwrite existing tiles in the cache.
If set to (by default), tiles that already exist on disk will be skipped.
cancellationToken CancellationToken
A cancellation token that can be used to cancel the operation before completion.
Returns¶
Task
A task representing the asynchronous operation.
Exceptions¶
Thrown if is not set or is not a .
Thrown if exceeds the number of available zoom levels in _zoomScales.
Thrown if the operation is canceled via the provided .
Remarks:
This method uses a throttled parallelism model to control concurrency and avoid overwhelming system resources. A maximum of 4 tile generation tasks are run concurrently using a SemaphoreSlim. Each tile is generated asynchronously and saved to the configured RasterXyzTileAsyncLayer.TileCache. TileCacheGenerated will be raised for each tile that is generated. Progress updates should be handled externally through events or UI bindings.
OnTileCacheGenerated(TileCacheGeneratedXyzTileAsyncLayerEventArgs)¶
protected void OnTileCacheGenerated(TileCacheGeneratedXyzTileAsyncLayerEventArgs e)
Parameters¶
e TileCacheGeneratedXyzTileAsyncLayerEventArgs
GetSnappedZoomMatrix(Double)¶
protected ValueTuple<int, TileMatrix> GetSnappedZoomMatrix(double scale)
Parameters¶
scale Double
Returns¶
GetTileAsyncCore(Int32, Int64, Int64, Single, CancellationToken)¶
protected abstract Task<RasterTile> GetTileAsyncCore(int zoomLevel, long x, long y, float resolutionFactor, CancellationToken cancellationToken)
Parameters¶
zoomLevel Int32
x Int64
y Int64
resolutionFactor Single
cancellationToken CancellationToken
Returns¶
Events¶
TileCacheGenerated¶
Occurs each time a tile is generated during the execution of RasterXyzTileAsyncLayer.GenerateTileCacheAsync(RectangleShape, Int32, Int32, Single, OverwriteMode, CancellationToken).
public event EventHandler<TileCacheGeneratedXyzTileAsyncLayerEventArgs> TileCacheGenerated;
DrawingException¶
public event EventHandler<DrawingExceptionLayerEventArgs> DrawingException;
DrawnException¶
public event EventHandler<DrawnExceptionLayerEventArgs> DrawnException;