Problems with CesiumTerrainProvider and heightmap-1.0 tiles

CesiumJS
1

Hi I am new to Cesium and trying to display some height tiles using CesiumTerrainProvider.

**I am currently getting error. “Failed to obtain terrain tile X: 1 Y: 0 Level: 0.” (Pretty sure I have followed the rules etc) **

Further debugging shows the reason as

message: "Invalid typed array length: 4225"

stack: "RangeError: Invalid typed array length: 4225↵ at new Uint16Array ()↵ at createHeightmapTerrainData (http://localhost:8080/Build/CesiumUnminified/Cesium.js:38221:28)

Which I’ll take to mean my tiles are invalid format. Does anyone have some good example heightmap-1.0 demo tiles that I can server up for testing purposes. Or even a url I can point at.

**I’ve looked at sandcastle demos but I don’t see any good examples using **CesiumTerrainProvider. Thanks in advance.

Alan

2

My problem was due to a compression issue now fixed. However I have created some dummy tiles hoping to see some heights on the map but it always looks flat

I have only created tiles to a zoom level of 2. Does this matter I have zoomed in only two levels? or will it only be obvious at very high levels of zoom. Is there a way to check what height is used etc in the rendered view (ie get height from map function).

Also if I only want height detail at a very high levels of zoom does this mean I still have to have tiles above this level with their child flags set true?

3

Hey Alan,

How are you creating your terrain tiles? For getting height, check out these two functions:

https://cesiumjs.org/Cesium/Build/Documentation/sampleTerrain.html?classFilter=Sample

https://cesiumjs.org/Cesium/Build/Documentation/sampleTerrainMostDetailed.html?classFilter=Sample

4

Thank you Omar I will check out these functions. I am only just starting out so there is still a lot to read and learn about Cesium.
I have written my own TMS server (.net core) and currently just making up random .terrain files for testing purposes. I have image tiles already working OK, so now just need to master height tiles and then finally a quantizedmesh terrain.

5

Best of luck Alan!

If you haven’t already seen it, the Quantized Mesh spec is probably a good resource when you get there: https://github.com/AnalyticalGraphicsInc/quantized-mesh

6

Dear Alan,
You wrote that your problem was due to compression issue.
Can you please elaborate?

7

You must have the wrong person. I have not used Cesium in over a year

1 Like
8

Thanks anyways.