[Tcl-bugs] [Tk] (anonymous) tkt (Open): On windows, arcs with small ' extent' can be drawn incorrectly

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Ticket Change [449652c13ab2610d8705e571fcfb2ae6c395281f827421362640d5c120663d1f]
  [On windows, arcs with small 'extent' can be drawn incorrectly]
  By      anonymous
  For     Tk
  On      2025-10-13T21:18:34.004
  Details https://core.tcl-lang.org/tk/tinfo?name=449652c13ab2610d8705e571fcfb2ae6c395281f827421362640d5c120663d1f
  Ticket  https://core.tcl-lang.org/tk/tktview/6051a9fca29285ce0b545c61413a713eeda33e01

Changed Fields
  icomment: Here's another test script that might demonstrate the problem a bit
            more clearly:

            package require Tk

            canvas .c -width 200 -height 200 -background black  pack .c -expand 1
            -fill both  pack [label .l -anchor w] -fill x  pack [label .l2 -text
            "Tk $tk_version"] -fill x

            set itm [.c create arc 2 2 199 199 \\  -outline pink \\  -fill red \\
            -extent 0.2]

            wm title . "Testing: $tcl_platform(os)"

            set start 0.1

            proc animate {} {  global start itm  set start [expr {$start +
            0.171671}]  .c itemconfigure $itm -start $start  .l configure -text
            $start  after 17 animate  }

            animate

            I've also attached a screenshot of this test script running on Tcl/Tk
            9.0 for windows (via wine, but the behaviour was identical on my
            friend's computer with windows 11), Tcl/Tk 8.6.12 on Linux, and a
            historical version of Tcl/Tk for comparison.

            It seems like the windows version of Tk has had this bug since at
            least late 1996.
  login:    anonymous

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