See attached bugdoc - start slideshow, on Linux, disable h/w acceleration - both gradients are rendered the same (cairocanvas renders them incorrectly, independently - that'll be dealt with in another bug).
Created attachment 61045 [details] bugdoc
Reason was basegfx ignoring aspect ratio for rect/square case. Ellipse/Circle is correct.
Thorsten Behrens committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=f7d3567c1bf6c9d77aa13a890610fb77c1545d9b Fix fdo#49508 incorrect square gradients in slideshow.
Thorsten Behrens committed a patch related to this issue. It has been pushed to "libreoffice-3-5": http://cgit.freedesktop.org/libreoffice/core/commit/?id=f3ee7a8a463af1fde6ed0da91abb654b25a3ecd9&g=libreoffice-3-5 Fix fdo#49508 incorrect square gradients in slideshow. It will be available in LibreOffice 3.5.4.
Created attachment 65445 [details] Testcases for gradient style type square I use LibreOffice 3.6.0 and the bug is not fixed. (1) The style type "square" is not square. (2) Die Presentation is different (and correctly square) for small step numbers. Please open the file in OOo3.2 to see, that a square gradient is really square in all cases. (If someone want it similar to Microsoft PowerPoint he has to use the type rectangle, not type square.)
Armin Le Grand committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=ed43421545c86f85b5fc4b9a33be077748fb8487 Resolves: fdo#49508# #i120539# Fixed visualisation of gradient 'square' The patch should be included in the daily builds available at http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More information about daily builds can be found at: http://wiki.documentfoundation.org/Testing_Daily_Builds Affected users are encouraged to test the fix and report feedback.
Looks fixed to me, kudos to Armin for the patch.