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forEachLayerAtPixel gives error for WebGLTile Layer

See original GitHub issue

Describe the bug

I receive the following error when implementing a singleclick event for a map with a WebGLTile layer + GeoTiff source:

util.js:9 Uncaught Error: Unimplemented abstract method.
    at util.js:9
    at abstract (util.js:10)
    at WebGLTileLayerRenderer.push../node_modules/ol/renderer/Layer.js.LayerRenderer.getDataAtPixel (Layer.js:133)
    at CompositeMapRenderer.push../node_modules/ol/renderer/Composite.js.CompositeMapRenderer.forEachLayerAtPixel (Composite.js:167)
    at Map.push../node_modules/ol/PluggableMap.js.PluggableMap.forEachLayerAtPixel (PluggableMap.js:560)
    at Map.<anonymous> (MapViewer.vue:179)
    at Map.push../node_modules/ol/events/Target.js.Target.dispatchEvent (Target.js:116)
    at Map.push../node_modules/ol/PluggableMap.js.PluggableMap.handleMapBrowserEvent (PluggableMap.js:897)
    at MapBrowserEventHandler.push../node_modules/ol/events/Target.js.Target.dispatchEvent (Target.js:116)
    at MapBrowserEventHandler.<anonymous> (MapBrowserEventHandler.js:129)

To Reproduce

Can’t provide a codesandbox right now due to the txml issue, but use the COG basic example and add something like:

			map.on('singleclick', evt => {
				const pixel = this.map.getEventPixel(evt.originalEvent);
				map.forEachLayerAtPixel(pixel, layer => {
					console.log(pixel);
					console.log(layer);
				});
			});

OpenLayers version 6.8.1.

Expected behavior Be able to get pixel values.

Issue Analytics

State:
Created 2 years ago
Comments:6 (5 by maintainers)

Top GitHub Comments

1reaction

valluzzicommented, Oct 5, 2021

Is there any way to get the real data value of the pixel? (not the styled one).
in https://codesandbox.io/s/cog-forked-dqreb?file=/main.js example the source is a RGBA source and in this case it returns the rgba value that is also the real value. But in case of a style that classify the data, this example will return the color of styled pixel, not the original pixel data value. Can anyone suggest some solution or approach?

1reaction

mike-000commented, Sep 28, 2021

You can access the WebGL context by non-API methods https://codesandbox.io/s/cog-forked-dqreb?file=/main.js

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