Probably not a bug - but may as well report. Noticed in 4.5.0 but this goes back a long way.
When working on a map (not mine) that was using a line type 223 to scroll a floor I noticed that the floor was moving south even though the line was set to scroll north. I checked and the floor of the sector had been rotated 180°. "Fair enough" I thought, but then I did a bit more digging and noticed that the results were less predictable than I expected.
If a floor is rotated 90° or 270°, the floor still scrolls to the map's north.
If the floor is rotated 45° or 225° then the floor will scroll west.
If the floor is rotated 135°or 315° then the floor will scroll east.
So, I have no idea what is meant to be happening here.
The test map shows the effect. All of the pits are set to scroll by the same line - a line special 223 tagged to any sector with tag 1 and set to scroll the floor north at normal speed. The red triangles on the floor show the rotation of each sector (the top of the flat on the floor is pointing the same way as the arrow). The blue letters show NESW with respect to the map.
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