Bug 19122

Summary:	[965 OGLC] fog coordinates are not properly passed to fragment programs
Product:	Mesa	Reporter:	Ian Romanick <idr>
Component:	Drivers/DRI/i965	Assignee:	Ian Romanick <idr>
Status:	RESOLVED FIXED	QA Contact:
Severity:	normal
Priority:	medium
Version:	git
Hardware:	All
OS:	All
Whiteboard:
i915 platform:		i915 features:
Bug Depends on:
Bug Blocks:	20277

Description Ian Romanick 2008-12-16 17:07:25 UTC

The (new) piglit test fp-fog shows this bug.  The fragment.fogcoord state variable is supposed to contain {f, 0, 0, 1}.  On 965 it seems to be getting {f, 1, GARBAGE, 0}.  See the output from fp-fog:

GL_RENDERER = Mesa DRI Intel(R) 965GM GEM 20080716
0.5, 1.5 => { 0.298039 1.000000 0.000000 0.000000 }
1.5, 1.5 => { 0.600000 1.000000 0.000000 0.000000 }
0.5, 0.5 => { 0.800000 1.000000 0.082353 0.000000 }
1.5, 0.5 => { 0.400000 1.000000 0.000000 0.000000 }

Comment 1 Eric Anholt 2009-03-23 22:58:08 UTC

commit 411d913ccea362dbd75411266d7abb685214ee93
Author: Eric Anholt <eric@anholt.net>
Date:   Mon Mar 23 22:35:03 2009 -0700

    i965: Fix fog coordinate g,b,a values when glFrontFacing isn't used.
    
    Previously, we would sample (f,glFrontFacing,undef,undef) instead of the
    (f,0,0,1) that fragment.fogcoord is supposed to return.  Due to
    glFrontFacing's presence in FOGC.y, we'll still give bad results there when
    glFrontFacing is used.
    
    Bug #19122, piglit testcase fp-fog.

Comment 2 Adam Jackson 2009-08-24 12:31:20 UTC

Mass version move, cvs -> git

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