Last weekend, I finished reading Down by the River Where the Dead Men Go by George Pelecanos. At the end of the book, there is an interview with him (which you can find here), where he is asked how he builds his fictional world. That is his answer:
"This is going to sound like smoke, but it's really all there in my head.
I've created this parallel, fictional world of Washington, D.C. that is alive to me all the
time. I've always been a daydreamer. Even when I was a kid, delivering food for my dad in
downtown D.C. I was making up movies in my head all day long while I walked the streets. And I'm still doing it today."
I strongly relate to this. I am a daydreamer since childhood. I guess all children are, but in my case I never grew up. When I was at school, when I was bored at home, when I couldn't sleep, and later on when I was bored commuting or bored at work. I still do it. I think the challenge is channelling it into a form, it is finding the discipline. But that the inspiration from a great crime writer comes from daydream, I find it encouraging.