Editing Scroll Floor

{{LineSpecial|description=This is the parameterized scrolling special for the floor.
|usage='''Scroll_Floor'''(''tag'', ''flags'', ''type'', ''x'', ''y'')
|parameters=
*''tag'': tag of sectors whose floors to scroll;
*''flags'': zero or a sum of the following values:
:*1: set [[displacement scrolling]]
:*2: set [[accelerative scrolling]]. This overrides displacement scrolling if both flags are set.
:*4: use linedef vector to direct the scrolling (scrolling will happen wherever the linedef points on the map). Divide the length of the line by 32 to obtain the scrolling velocity. Parameters ''x'' and ''y'' will be ignored.
*''type'': type of scroller. Can be:
:*0: scroll only the texture;
:*1: only carry the things, without animating the texture;
:*2: both scroll the texture and carry things.
*''x'', ''y'': if ''flags'' doesn't include 4, then these parameters control the scrolling direction. Please see in '''Notes''' about how they're scaled.
|notes=This special acts ''static'' when set on a linedef: it triggers at map startup, not when activated by player or others. But it can also be called from [[ACS]].
|udmf=223
|extradata=484

Scales of ''x'' and ''y'' differ between map placement and ACS:
*on the map, due to Hexen format legacy, you need to subtract 128 from the parameter, then divide by 32, to obtain the actual direction.
*in ACS: multiply by 10, then divide by 32.}}