Writing tools for Interactive Media

Celtx

"An all-in-one system for writing, planning, and collaborating on video and game productions"

https://www.celtx.com/index.html

ChatMapper

"ChatMapper is an easy to use tool for writing and testing nonlinear dialogue and events for fields where complex problems are the normal, such as entertainment, e-learning, emergency response, diagnoses health care, sales and customer service, and strategic planning."

http://www.chatmapper.com

Twine

Often used to demonstrate interactive storylines - not so much to prepare for shooting them.

"Twine is an open-source tool for telling interactive, nonlinear stories. You don't need to write any code to create a simple story with Twine, but you can extend your stories with variables, conditional logic, images, CSS, and JavaScript when you're ready. Twine publishes directly to HTML, so you can post your work nearly anywhere. Anything you create with it is completely free to use any way you like, including for commercial purposes."

http://twinery.org

ChoiceScript

"ChoiceScript is a simple programming language for writing multiple-choice games (MCGs) like Choice of the Dragon. Writing games with ChoiceScript is easy and fun, even for authors with no programming experience."

https://www.choiceofgames.com/make-your-own-games/choicescript-intro/