Displaying newlines as whitespaces on a region.

["Daniel P. Gomez" <d.gomez@posteo.org>]

Dear Emacs friends,

I use Org mode for prose and keep my files under version control 
(VC).
To keep VC diffs simple and meaningful, I would like to write a 
single sentence in each line, as shown in the following example 
(between dashes):

---
* A heading

This is an example.
In the example each sentence is in a newline.
Sentences within a paragraph look ugly when separated by newlines, 
though.

Two newlines represent a paragraph, just as in LaTeX.
---

Although writing one sentence per line is good for VC, it is 
hardly convenient for reading and writing, because this is not how 
people are used to prose, generally.

Currently the question arose whether it'd be possible to have 
Emacs display newline characters as whitespaces. A naive solution 
could be achieved by tweaking the variable 
=whitespace-display-mappings= and activating 
=whitespace-newline-mode=, which is a part of Emacs.
Unfortunately, however, this solution has a series of drawbacks. 
First, it is no longer possible to visually differentiate between 
paragraphs, as they'd be displayed as sentences separated by two 
whitespaces. Second, headings and org src blocks get clumped.

Would anyone know how to have =whitespace-newline-mode= only 
substitute newlines for whitespaces in sentences outside of org 
blocks, tables and headings and only for sentences followed by 
other sentences (effectively allowing for paragraph breaks)? More 
generally, would anyone know of a solution to this problem even if 
using other packages other than whitespace.el?

Ideally the example above would be displayed in the buffer as:

---
* A heading

This is an example. In the example each sentence is in a newline. 
Sentences within a paragraph look ugly when separated by newlines, 
though.

Two newlines represent a paragraph, just as in LaTeX.
---

Thank you.

Yours,

Daniel Gomez