Bug 126538

Summary: [WebGL] FBO Depth Buffer Attachment Function Improperly Clearing With 0
Product: WebKit Reporter: Brent Fulgham <bfulgham>
Component: WebGLAssignee: Brent Fulgham <bfulgham>
Status: RESOLVED FIXED    
Severity: Normal CC: bfulgham, commit-queue, dino, esprehn+autocc, gyuyoung.kim, kondapallykalyan, p.szymanski3, roger_fong, tomeu
Priority: P2 Keywords: InRadar
Version: 528+ (Nightly build)   
Hardware: All   
OS: All   
Bug Depends on: 36248    
Bug Blocks:    
Attachments:
Description Flags
Patch dino: review+

Description Brent Fulgham 2014-01-06 14:03:47 PST 
The problem was introduced in 2010 under https://bugs.webkit.org/show_bug.cgi?id=36248.

The depth buffer should be initialized to 1.0f (rather than 0.0f) to match expected initialization behavior.  The current logic was setting the depth buffer to 1.0, blocking all drawing operations, unless an explicit "gl.clear(gl.DEPTH_BUFFER_BIT)" was being done immediately after attaching the depth FBO.

Found by webgl/1.0.2/resources/webgl_test_files/conformance/renderbuffers/framebuffer-object-attachment.html
Comment 1 Brent Fulgham 2014-01-06 14:04:35 PST 
<rdar://problem/15201336>
Comment 2 Brent Fulgham 2014-01-06 14:08:38 PST 
Created attachment 220455 [details]
Patch
Comment 3 Brent Fulgham 2014-01-06 14:39:55 PST 
Committed r161375: <http://trac.webkit.org/changeset/161375>
Comment 4 Brent Fulgham 2014-01-07 09:15:35 PST 
*** Bug 81290 has been marked as a duplicate of this bug. ***
Comment 5 Brent Fulgham 2014-01-10 10:27:18 PST 
*** Bug 122264 has been marked as a duplicate of this bug. ***
Comment 6 Martin Robinson 2014-04-08 16:17:13 PDT 
*** Bug 94300 has been marked as a duplicate of this bug. ***