In Renaissance typography, one often sees paragraphs end with a triangular "fade out", e.g.
Is there a clever way to do this in LaTeX? You can get an approximation with manual line breaks in a \centering block, but it's imperfect in many ways. A solution exists for a pure triangle using \shapepar, however, I cannot see how to merge this with the rest of the justified-aligned paragraph. Ideally the solution would not depend on ad-hoc tuning to the specific text.
Another previous answer using \shapepar exists, however, like before, it does not merge automatically with the preceding justified-aligned part of the paragraph---instead the widths are different, and the parameters defining the shape of the triangle must be fine-tuned to fix this. Subsequently, if we change even a single character within the triangle, we have to restart this painstaking job.
Further, it does not allow a page break within the formatted paragraph. I already know how to hack this together by tuning the previous solutions and manually starting a new paragraph at a "start point" that is after a non-broken word nearly at the end of a line before the triangle begins (e.g. we could end a paragraph after "Coniugem ama." in the image above.) But after this, we can't change the text in the entire justified paragraph without destroying it.
Is there a way to do this triangular alignment in a way which automatically merges with the justified part of the paragraph without ad-hoc tuning to the specific text, and which allows page breaks in that paragraph?
