It was never meant to be a movie, but I always wrote very visually, so it wasn't a big leap for me to make from writing fiction to screenplays. I had gone written it after reading a book on writing screenplays, and I gave it to my actress friend, to see if it read like a screenplay was supposed to, because I had no clue what I was doing. Then I went home to visit my parents for two weeks, to borrow some money, I think, because I was starving at the time. While I was away, she kept giving it to other friends of ours from Bard to read, because she thought it was so good. Any writer sees their characters living and breathing, whether they're writing a novel or poem, haiku or play or whatever.
Writers tend to see their people, their characters, moving in real time.
So it isn't that big of a difference for me between writing fiction and screenplays. The only real difference is the structure of the writing, and it's actually kind of liberating to have a structure imposed on you. It's more freedom than less. But casting is a whole other thing. Basically what you want to do is write your first draft, give birth to your baby, and then watch as you send it off to day care, and it can either get molested or abused, or coddled.