We have an application that uses Cesium 1.39. Unfortunately our client is getting an error when they access it.
They get this error:
Error: Unexpected call to method or property access.
With a stack trace with the top line of code:
As a test I had them access https://cesiumjs.org/ to rule out our application code and they said they get the same "Error: Unexpected call to method or property access".
Looking up the minified Cesium.js code, that line/col 511:3888 seems to be e.linkProgram(l); which searching the 1.39 source code seems to be Source/Renderer/ShaderProgram.js gl.linkProgram(program) inside the method createAndLinkProgram(gl, shader).
So something weird going on with WebGL in the client's environment? That method has already done a bunch of other work on that gl object before it gets to linkProgram and falls over.
This is happening to many machines at the client's site. I've been able to get information from 2 of the affected machines.
One is Windows 7, the other hasn't been confirmed yet.
Both use IE11, one is version 11.0.9600.18837 the other is 11.0.9600.18893.
Both machines have run the webglreport.com, which I've got screenshots but can't attach them here by the looks.
Both reports come back identically:
"This browser supports webgl 1"
GL Version: WebGL 0.94
Shading Language Version: WebGL GLSL ES 0.94
Unmasked Renderer: Intel(R) HD Graphics 530
Major Performance Caveat: No
These WebGL reports are almost identical to my own machine (which works fine with IE11 of course!), the only slight difference being I have Intel® HD Graphics 520.
I'm a bit unsure how to proceed with resolving this now. I don't know if its something awry in the Cesium code or something weird in the way the client's environment is setup that goes deeper than what the WebGL report shows.
Thanks in advance for your time, any suggestions would be gratefully received!