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Bug 336900 - Matrix determinant algorithm is possibly wrong
Summary: Matrix determinant algorithm is possibly wrong
Status: CLOSED INVALID
Alias: None
Product: z_Archived
Classification: Eclipse Foundation
Component: Gef3d (show other bugs)
Version: unspecified   Edit
Hardware: PC All
: P3 normal (vote)
Target Milestone: ---   Edit
Assignee: Project Inbox CLA
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Reported: 2011-02-11 02:37 EST by Kristian Duske CLA
Modified: 2021-03-23 18:16 EDT (History)
1 user (show)

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Description Kristian Duske CLA 2011-02-11 02:37:52 EST 
I am not sure, but I think the Math3DMatrix4f#determinant(IMatrix4f) method is wrong. It does not seem to develop the determinant after row 1, as it says in the comment. The determinants of the the comatrices are wrong (they seem to be calculated by the Sarrus method for 2x2 matrices instead of 3x3).
Comment 1 Jens Von Pilgrim CLA 2011-02-11 06:41:49 EST 
Added long documentation on how the determinant is calculated, also implemented some tests. Seems as if everything works correctly. Renamed the local variables (and changed some signs) to make the algorithm clearer, however it worked correctly.

(I suggest to add a price for this bug: a cocktail at Becketts Kopf, what you think ;-) )