WebGL error on IE 11 with cubemap

[mpetroff]

WebGL error on IE 11 with cubemap

[mpetroff]

After doing some testing in a VM, this seems to be a bug in IE's WebGL support; specifically, IE 11 doesn't support non-power-of-two cube map textures (I was able to find another reference to this IE bug). What's even more troubling is that IE 11 doesn't report the error through the JavaScript API, so Pannellum can't display an error message. The new Edge engine in the Windows 10 Technical Preview engine still doesn't support the NPOT textures, but it at least reports the error to Pannellum.

[mpetroff]

Safari under iOS has a similar issue with NPOT cubemaps not working but no error being generated (tested on iPhone 5c / iOS 8.1.3).

[mpetroff]

I just added a user agent check to display an error for NPOT cubemaps in IE 11. While this is generally bad practice as one should check for features instead, IE 11 claims to have the feature, but it doesn't actually work. The only other way to check for this would be to build in a WebGL conformance check to see if it actually worked, but that's much too complex for something like this, in my opinion.

[umbreak]

What about this: https://www.khronos.org/webgl/wiki/WebGL_and_OpenGL_Differences#Non-Power_of_Two_Texture_Support

Some other players support cubemaps and WebGL, so there may be some workarround.

Thanks!

[mpetroff]

To be standards compliant with WebGL, NPOT textures without mipmaps need to be supported. Firefox and Chrome support this, but IE 11 and Safari on iOS both don't support any NPOT cubemap textures. Additionally, they don't throw an error.