Fragment shader compilation fails on Samsung GT P-5100 (Firefox Mobile)

[Dexterp37]

I've been trying to test CesiumJS on my Android Samsung Galaxy Tab 2 10.1 tablet (GT P-5100). Unfortunately, the Hello World sample fails to load and displays a fragment shader compilation error.

OS: Android 4.2.2
Browser: Firefox for Android 27.0

13:43:57.989 "[GL] Fragment shader compile log: Compile failed." Cesium.js:80035
13:43:58.003 "An error occurred while rendering.  Rendering has stopped. RuntimeError: Fragment shader failed to compile.  Compile log: Compile failed.

RuntimeError@http://10.20.64.183:8080/Cesium/Cesium.js:6618
createAndLinkProgram@http://10.20.64.183:8080/Cesium/Cesium.js:80036
ShaderProgram@http://10.20.64.183:8080/Cesium/Cesium.js:79747
Context.prototype.createShaderProgram@http://10.20.64.183:8080/Cesium/Cesium.js:83480
ShaderCache.prototype.getShaderProgram@http://10.20.64.183:8080/Cesium/Cesium.js:77204
ShaderCache.prototype.replaceShaderProgram@http://10.20.64.183:8080/Cesium/Cesium.js:77182
EllipsoidPrimitive.prototype.update@http://10.20.64.183:8080/Cesium/Cesium.js:61718
Moon.prototype.update@http://10.20.64.183:8080/Cesium/Cesium.js:103568
updatePrimitives@http://10.20.64.183:8080/Cesium/Cesium.js:107759
Scene.prototype.render@http://10.20.64.183:8080/Cesium/Cesium.js:107812
CesiumWidget.prototype.render@http://10.20.64.183:8080/Cesium/Cesium.js:116558
render@http://10.20.64.183:8080/Cesium/Cesium.js:116091" Cesium.js:116104
13:43:57.988 Error: WebGL: linkProgram: a fragment shader used in this program failed to compile, with this log:
Compile failed.

[mramato]

Thanks for the report. Can you try with the latest Chrome on the same device? Firefox's WebGL support on mobile is not quite as robust and I want to rule out Firefox as the problem.

Also, can you post the results of http://webglreport.com/ on this device.

It's possible this is another manifestation of #817, according to wikipedia, the Tab 2 10.1 uses a PowerVR SGX540

I just verified that Cesium (at least the basics) does work in Firefox for Android 27.0 on a Nexus 7, so my guess is that this is chipset related.

[Dexterp37]

Thank you for your quick reply. I forgot to add that I've already tried the latest Chrome for Android (v32), but it was not working as well ("The browser supports WebGL, but initialization failed.").

Following your input, I went to the http://webglreport.com website and it reported the same thing. As reported on Chromium Issue Tracker ( https://code.google.com/p/chromium/issues/detail?id=306938#c5 ), it appears that Chrome for Android disables WebGL unless GPU reset notification is supported (which seems to be the case for PowerVR SGX540). In the previous link a workaround is also provided to force WebGL usage. This is the output of chrome://gpu/ for this tablet: http://pastebin.com/EtiN5r7p .

I will test it tomorrow on Chrome by forcing the WebGL support ON but, as you mentioned, this definitely seems like a chipset related issue.

[Dexterp37]

I've tried on Chrome 32 (for Android), after forcing WebGL on. After displaying the yellow globe (http://postimg.org/image/w29mkbg9f/a02db605/) for a second or two, Chrome suddenly crashes.

[pjcozzi]

Any update with the latest version of Android and Firefox or Chrome?

[pjcozzi]

No update in quite a while here. Closing.