DiscardMissingTileImagePolicy

new Cesium.DiscardMissingTileImagePolicy(options)
Scene/DiscardMissingTileImagePolicy.js 22

A policy for discarding tile images that match a known image containing a "missing" image.
Name Type Description
options Object Object with the following properties:
Name Type Default Description
missingImageUrl Resource | String The URL of the known missing image.
pixelsToCheck Array.<Cartesian2> An array of Cartesian2 pixel positions to compare against the missing image.
disableCheckIfAllPixelsAreTransparent Boolean false optional If true, the discard check will be disabled if all of the pixelsToCheck in the missingImageUrl have an alpha value of 0. If false, the discard check will proceed no matter the values of the pixelsToCheck.

Methods

isReady() → Boolean
Scene/DiscardMissingTileImagePolicy.js 100

Determines if the discard policy is ready to process images.
Returns:
True if the discard policy is ready to process images; otherwise, false.

shouldDiscardImage(image) → Boolean
Scene/DiscardMissingTileImagePolicy.js 112

Given a tile image, decide whether to discard that image.
Name Type Description
image HTMLImageElement An image to test.
Returns:
True if the image should be discarded; otherwise, false.
Throws:
  • DeveloperError : shouldDiscardImage must not be called before the discard policy is ready.