Variable: bidi-paragraph-direction

If non-nil, forces directionality of text paragraphs in the buffer.

If this is nil (the default), the direction of each paragraph is
determined by the first strong directional character of its text.
The values of `right-to-left' and `left-to-right' override that.
Any other value is treated as nil.

This variable has no effect unless the buffer's value of
`bidi-display-reordering' is non-nil.