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PointPush_SetForce(tag, tid, magnitude, use_line_vector)
This is a static special which sets up a pushing or pulling thing source.
- tag: if nonzero, it's tag of sectors containing push or pull things.
- tid: if tag is zero, this is the tag of push/pull things directly.
- magnitude: if use_line_vector is 0, use the magnitude from this value directly. It's equivalent of a horizontal line of this length
- use_line_vector: if 1, ignore magnitude and use the linedef length. Note that the resulting magnitude is not exact if the line is non-orthogonal (same calculation as AproxDistance codepointer). Warning: other values than 0 and 1 are reserved.