Module: ol/source/ImageCanvas

ol/source/ImageCanvas


Classes

ImageCanvasSource

Type Definitions

FunctionType()

source/ImageCanvas.js, line 10

A function returning the canvas element ({HTMLCanvasElement}) used by the source as an image. The arguments passed to the function are: module:ol/extent~Extent the image extent, {number} the image resolution, {number} the device pixel ratio, module:ol/size~Size the image size, and module:ol/proj/Projection the image projection. The canvas returned by this function is cached by the source. The this keyword inside the function references the module:ol/source/ImageCanvas.

Options{Object}

Properties:
Name Type Argument Default Description
attributions module:ol/source/Source~AttributionLike <optional>

Attributions.

canvasFunction module:ol/source/ImageCanvas~FunctionType <optional>

Canvas function. The function returning the canvas element used by the source as an image. The arguments passed to the function are: {module:ol/extent~Extent} the image extent, {number} the image resolution, {number} the device pixel ratio, {module:ol/size~Size} the image size, and {module:ol/proj/Projection~Projection} the image projection. The canvas returned by this function is cached by the source. If the value returned by the function is later changed then changed should be called on the source for the source to invalidate the current cached image. See: module:ol/Observable~Observable#changed

projection module:ol/proj~ProjectionLike

Projection.

ratio number <optional>
1.5

Ratio. 1 means canvases are the size of the map viewport, 2 means twice the width and height of the map viewport, and so on. Must be 1 or higher.

resolutions Array.<number> <optional>

Resolutions. If specified, new canvases will be created for these resolutions

state module:ol/source/State <optional>

Source state.