Bug 139024

Summary: WebGL Shader corruption with iPhone 5 on iOS 8.1.1
Product: WebKit Reporter: Mark Perris <markperris>
Component: WebGLAssignee: Nobody <webkit-unassigned>
Status: RESOLVED CONFIGURATION CHANGED    
Severity: Normal CC: dino, kkinnunen, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: 528+ (Nightly build)   
Hardware: iPhone / iPad   
OS: iOS 8.1   
URL: http://sqr.bartekdrozdz.com/html/lab/gl_ssao/
Attachments:
Description Flags
Screenshot of corruption visible on an iPhone 5. none

Description Mark Perris 2014-11-24 03:43:59 PST 
Created attachment 242155 [details]
Screenshot of corruption visible on an iPhone 5.

Running the following example on an iPhone 5 with iOS 8.1.1 causes corrupted output, per the screenshot attached.

http://sqr.bartekdrozdz.com/html/lab/gl_ssao/

The same style of corruption is also visible on certain examples on ShaderToy.
The ShaderToy examples work correctly with an iPhone 6, suggesting it could be a driver bug.
I'll test this specific example on an iPhone 6 when I head past the Apple Store tonight.
Comment 1 Mark Perris 2014-11-24 09:25:08 PST 
I can confirm in this specific example, the bug is also present on the iPhone 6, though with slightly different artefacts.
Comment 2 Dean Jackson 2014-11-24 19:13:30 PST 
Thanks!
Comment 3 Radar WebKit Bug Importer 2014-11-24 19:13:44 PST 
<rdar://problem/19076434>