Bug 8701 - Incorrect line clipping with very large coordinates
Summary: Incorrect line clipping with very large coordinates
Status: RESOLVED MOVED
Alias: None
Product: Mesa
Classification: Unclassified
Component: Mesa core (show other bugs)
Version: 6.5
Hardware: x86 (IA32) Linux (All)
: high normal
Assignee: mesa-dev
QA Contact:
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Blocks:
 
Reported: 2006-10-18 14:40 UTC by Brian Paul
Modified: 2019-09-18 20:21 UTC (History)
0 users

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Attachments
demo program (869 bytes, text/x-csrc)
2006-10-18 14:41 UTC, Brian Paul 		Details
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Description Brian Paul 2006-10-18 14:40:22 UTC 
Mesa's line clipping code fails when a vertex coordinate is of very large magnitude.
Comment 1 Brian Paul 2006-10-18 14:41:06 UTC 
Created attachment 7460 [details]
demo program
Comment 2 Brian Paul 2006-10-18 14:43:26 UTC 
The problem boils down to computing t = -2.e8 / (-2.e8 - 3.5)

We wind up with t=1, but t should instead be some value very close to, but less
than 1.0.  Tried double precision with no change.  Will have to study this
further someday.
Comment 3 chemtech 2013-03-15 14:22:15 UTC 
Brian Paul
Do you still experience this issue with newer soft ?
Please check the status of your issue.
Comment 4 Brian Paul 2013-03-15 15:18:27 UTC 
Unfortunately, swrast, softpipe and llvmpipe all still suffer from this.
Comment 5 GitLab Migration User 2019-09-18 20:21:54 UTC 
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/mesa/mesa/issues/956.

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