ThinkGeoMBTilesLayer¶
Namespace: ThinkGeo.Core
Provides read/write access to legacy ThinkGeo-specific MBTiles databases, including tile generation helpers.
public class ThinkGeoMBTilesLayer : Layer
Inheritance object → LayerBase → Layer → ThinkGeoMBTilesLayer
Properties¶
ProjectionConverter¶
Gets or sets the projection converter used when reading or writing tile coordinates.
public ProjectionConverter ProjectionConverter { get; set; }
Property Value¶
BitmapTileCache¶
Gets or sets the cache used to store rendered bitmap tiles.
public RasterTileCache BitmapTileCache { get; set; }
Property Value¶
StyleJsonUri¶
Gets or sets the Mapbox style json used to interpret vector tiles.
public Uri StyleJsonUri { get; set; }
Property Value¶
DrawingQuality¶
Gets or sets the drawing quality applied when rasterizing vector tiles.
public DrawingQuality DrawingQuality { get; set; }
Property Value¶
ShowDebugInfo¶
Gets or sets a value indicating whether debug tile boundaries and metadata are rendered.
public bool ShowDebugInfo { get; set; }
Property Value¶
TileSize¶
Gets or sets the tile size (in pixels) expected by the MBTiles dataset.
public int TileSize { get; set; }
Property Value¶
RequestDrawingInterval¶
Gets or sets the interval between automatic draw requests. Obsolete.
public TimeSpan RequestDrawingInterval { get; set; }
Property Value¶
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.
DrawingTime¶
Gets the last recorded drawing time for the layer.
public TimeSpan DrawingTime { get; protected set; }
Property Value¶
TimeSpan
The duration of the most recent draw operation.
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¶
Gets or sets how drawing exceptions are handled when the layer renders.
public DrawingExceptionMode DrawingExceptionMode { get; set; }
Property Value¶
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).
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¶
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.
HasBoundingBox¶
Gets a value indicating whether the layer supports retrieving its bounding box.
public bool HasBoundingBox { get; }
Property Value¶
Remarks:
When this property is false, calls to or GetFullExtent throw an exception. The default implementation returns false.
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.
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¶
WrappingExtent¶
Gets or sets the geographic extent to use when wrapping is enabled.
public RectangleShape WrappingExtent { get; set; }
Property Value¶
Constructors¶
ThinkGeoMBTilesLayer()¶
Initializes a new instance of the ThinkGeoMBTilesLayer class without a backing database.
public ThinkGeoMBTilesLayer()
ThinkGeoMBTilesLayer(string)¶
Initializes a new instance of the ThinkGeoMBTilesLayer class that opens the specified MBTiles database.
public ThinkGeoMBTilesLayer(string mbTilesPathFilename)
Parameters¶
mbTilesPathFilename string
Path to the MBTiles database.
ThinkGeoMBTilesLayer(string, Uri)¶
Initializes a new instance of the ThinkGeoMBTilesLayer class and associates an optional style json.
public ThinkGeoMBTilesLayer(string mbTilesPathFilename, Uri styleJsonUri)
Parameters¶
mbTilesPathFilename string
Path to the MBTiles database.
styleJsonUri Uri
URI that points to a Mapbox style json used for rendering.
Methods¶
CloseCore()¶
Provides the overridable implementation that closes the instance and releases any resources it holds.
protected void CloseCore()
Returns¶
OpenCore()¶
Provides the overridable implementation that opens the instance and initializes the resources it depends on.
protected void OpenCore()
Returns¶
GetBoundingBoxCore()¶
Provides the overridable implementation that returns the bounding box that encloses the relevant geometry.
protected RectangleShape GetBoundingBoxCore()
Returns¶
RectangleShape
The result of the operation.
GetRasterContentTypeCore()¶
ThinkGeo vector MBTiles are rendered cartographically.
protected RasterContentType GetRasterContentTypeCore()
Returns¶
GetTile(long, long, long)¶
Retrieves a vector tile from the MBTiles database at the provided XYZ indices.
public VectorTile GetTile(long zoom, long x, long y)
Parameters¶
zoom long
Zoom level of the tile.
x long
Column index of the tile.
y long
Row index of the tile.
Returns¶
VectorTile
The matching if it exists; otherwise null.
LoadStyleJson()¶
Loads and parses the style json referenced by ThinkGeoMBTilesLayer.StyleJsonUri.
public void LoadStyleJson()
Returns¶
DrawTileAsync(GeoCanvas, int, long, long)¶
Draws a tile directly to the provided canvas using the layer’s style and MBTiles data.
public Task DrawTileAsync(GeoCanvas canvas, int zoomIndex, long columnIndex, long rowIndex)
Parameters¶
canvas GeoCanvas
Canvas that receives the rendered tile.
zoomIndex int
Zoom level index.
columnIndex long
Tile column to draw.
rowIndex long
Tile row to draw.
Returns¶
6R4=(GeoCanvas, int, long, long, ZoomLevelSet, bool, RasterTileCache, int, List<string>, H0M=, bool, int, RasterResamplingMode)¶
internal static Task 6R4=(GeoCanvas canvas, int zoomIndex, long columnIndex, long rowIndex, ZoomLevelSet zoomLevelSet, bool ShowDebugInfo, RasterTileCache BitmapTileCache, int maxZoom, List<string> pbfLayerNames, H0M= getFeaturesFromPbfVectorTileAsyncDelegate, bool useLegacyLabeling, int tileSize, RasterResamplingMode resamplingMode)
Parameters¶
canvas GeoCanvas
zoomIndex int
columnIndex long
rowIndex long
zoomLevelSet ZoomLevelSet
ShowDebugInfo bool
BitmapTileCache RasterTileCache
maxZoom int
pbfLayerNames List<string>
getFeaturesFromPbfVectorTileAsyncDelegate H0M=
useLegacyLabeling bool
tileSize int
resamplingMode RasterResamplingMode
Returns¶
6h4=(int, long, long, RectangleShape, CancellationToken, int, List<string>, IEM=)¶
internal static Collection<Feature> 6h4=(int zoom, long x, long y, RectangleShape boundingBox, CancellationToken cancellationToken, int maxZoom, List<string> pbfLayerNames, IEM= getFeaturesFromPbfVectorTile)
Parameters¶
zoom int
x long
y long
boundingBox RectangleShape
cancellationToken CancellationToken
maxZoom int
pbfLayerNames List<string>
getFeaturesFromPbfVectorTile IEM=
Returns¶
6x4=(int, long, long, RectangleShape, CancellationToken, int, List<string>, H0M=)¶
internal static Task<Collection<Feature>> 6x4=(int zoom, long x, long y, RectangleShape boundingBox, CancellationToken cancellationToken, int maxZoom, List<string> pbfLayerNames, H0M= getFeaturesFromPbfVectorTileAsync)
Parameters¶
zoom int
x long
y long
boundingBox RectangleShape
cancellationToken CancellationToken
maxZoom int
pbfLayerNames List<string>
getFeaturesFromPbfVectorTileAsync H0M=
Returns¶
7R4=(ZoomLevelSet, int)¶
internal static List<string> 7R4=(ZoomLevelSet zoomLevelSet, int zoomLevelIndex)
Parameters¶
zoomLevelSet ZoomLevelSet
zoomLevelIndex int
Returns¶
DrawCore(GeoCanvas, Collection<SimpleCandidate>)¶
Provides the overridable implementation that draws onto and appends any label candidates to .
protected void DrawCore(GeoCanvas canvas, Collection<SimpleCandidate> labelsInAllLayers)
Parameters¶
canvas GeoCanvas
The to draw to.
labelsInAllLayers Collection<SimpleCandidate>
A shared collection that receives label candidates generated during drawing.
Returns¶
OnGeneratingTile(GeneratingTileMBTilesLayerEventArgs)¶
Performs on generating tile.
protected void OnGeneratingTile(GeneratingTileMBTilesLayerEventArgs e)
Parameters¶
e GeneratingTileMBTilesLayerEventArgs
The e.
Returns¶
OnGeneratedTile(GeneratedTileMBTilesLayerEventArgs)¶
Performs on generated tile.
protected void OnGeneratedTile(GeneratedTileMBTilesLayerEventArgs e)
Parameters¶
e GeneratedTileMBTilesLayerEventArgs
The e.
Returns¶
BeginTransaction()¶
Begins a batch transaction so multiple tile changes can be committed atomically.
public void BeginTransaction()
Returns¶
CommitTransaction()¶
Commits the currently buffered tile edits to the database.
public TransactionResult CommitTransaction()
Returns¶
TransactionResult
A that summarizes the applied changes.
WriteMetaData(string, string)¶
Writes or updates a metadata entry in the MBTiles database.
public void WriteMetaData(string key, string value)
Parameters¶
key string
Metadata key.
value string
Metadata value.
Returns¶
CreateDatabase(string, bool)¶
Creates a ThinkGeo MBTiles database with the required schema.
public static void CreateDatabase(string mbTilesPath, bool isOverwrite)
Parameters¶
mbTilesPath string
Destination path for the database.
isOverwrite bool
True to overwrite an existing file; otherwise false.
Returns¶
AddTile(VectorTile)¶
Adds a new tile to the database.
public void AddTile(VectorTile vectorTile)
Parameters¶
vectorTile VectorTile
Tile to add.
Returns¶
UpdateTile(VectorTile)¶
Updates an existing tile in the database.
public void UpdateTile(VectorTile vectorTile)
Parameters¶
vectorTile VectorTile
Tile content to write.
Returns¶
DeleteTile(VectorTile)¶
Deletes a tile from the database.
public void DeleteTile(VectorTile vectorTile)
Parameters¶
vectorTile VectorTile
Tile that identifies the zoom/x/y to remove.
Returns¶
Events¶
GeneratingTile¶
Occurs before a tile is generated, allowing the operation to be cancelled.
public event EventHandler<GeneratingTileMBTilesLayerEventArgs> GeneratingTile;
GeneratedTile¶
Occurs after a tile has been generated.
public event EventHandler<GeneratedTileMBTilesLayerEventArgs> GeneratedTile;
DrawingProgressChanged¶
Occurs as the layer reports drawing progress (useful for async or tiled rendering scenarios).
public event EventHandler<DrawingProgressChangedEventArgs> DrawingProgressChanged;
RequestedDrawing¶
Raised after the drawing buffer elapses so consumers can handle a legacy drawing cycle. Obsolete.
public event EventHandler<RequestedDrawingLayerEventArgs> RequestedDrawing;
RequestingDrawing¶
Raised before the drawing buffer elapses so consumers can cancel a legacy drawing operation. Obsolete.
public event EventHandler<RequestingDrawingLayerEventArgs> RequestingDrawing;
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;