sampleHeight bug

[hieeyh]

code:
let cartographicPosition = new Cesium.Cartographic()
cartographicPosition.longitude = mapUtil.angleToRadian(113.939499)
cartographicPosition.latitude = mapUtil.angleToRadian(22.5262237)
let takeOffheight = scene.sampleHeight(cartographicPosition)

result:
TypeError: Cannot read property 'x' of undefined
at n (Cesium.js:445)
at Function.s.fromCartesian (Cesium.js:445)
at we.sampleHeight (Cesium.js:526)

[lilleyse]

Hi @hieeyh

What happens when you click "Sample height" and "Sample height supported" in this demo?

Demo

It's possible that sampleHeight isn't supported on your setup. sampleHeightSupported would be the first thing to check.

[hieeyh]

Hi @hieeyh

What happens when you click "Sample height" and "Sample height supported" in this demo?

Demo

It's possible that sampleHeight isn't supported on your setup. sampleHeightSupported would be the first thing to check.

If theris a 2D billboard, it will report this error. But if exclude this 2D billboard, sometimes success, sometimes fail.

[lilleyse]

Thanks @hieeyh, I can replicate the bug with this example.

It throws the error if the picked object doesn't write depth, like when disableDepthTestDistance : Number.POSITIVE_INFINITY is set in the example. The fix would be to pick through those objects. I should be able to incorporate the fix in #7115.

As a workaround you can add any billboards or other objects not meant to be sampled to the objectsToExclude array: https://cesiumjs.org/Cesium/Build/Documentation/Scene.html?classFilter=Scene#sampleHeight.

[lilleyse]

The example I posted should now work in #7115.

Example on offscreen-picking branch

@hieeyh if you have a chance would you mind testing your app with this build to see if it fixed your problem?

A link to download the build is here: http://cesium-dev.s3-website-us-east-1.amazonaws.com/cesium/offscreen-picking/Cesium-1.49.0-offscreen-picking29051.zip