The RichTextArea control (JDK-8301121), or any custom control that needs non-trivial navigation within complex or wrapped text needs a public API to get information about various aspects of the text layout.

One possibility is to add a new method to Text / TextFlow:
  public LayoutInfo getLayoutInfo()

Where LayoutInfo structure provides methods for querying the following information:

- text lines: offsets and bounds
- overall layout bounds
- text selection geometry (JDK-8341672)
- strike-through geometry (JDK-8341672)
- underline geometry (JDK-8341672)

The line bounds obtained via LayoutInfo might help address JDK-8091012 "[Text] No way to distinguish between a hit to the last character and a hit beyond the end of text", albeit indirectly.

The RichTextArea requires such a public API in TextFlow only, but we'll basically get the same functionality for Text node for free.

See also
https://github.com/andy-goryachev-oracle/Test/blob/main/doc/Text/LayoutInfo.md