Hard to compare. They’re completely different in terms of plot, mood, style… everything, really. Roadside Picnic has the signature Strugatsky Bros dark comedy running through it, while Stalker really has no comedic elements whatsoever. I prefer the book, for what it’s worth. OTOH, I prefer the film Solaris to the Lem novel.

I need to reread Solaris. I read it when I was like 14 so it was a bit beyond me at the time.

Coincidentally, the German translation of Roadside Picnic has an afterword by Lem.

IMO the Stalker game is like the darkest and most raw take of the general theme, the movie is the most philosophical and artsy take and the book is somewhere in the middle. And they’re all worth it.

I think the Stalker game bears little to no relation to the novel. The novel is not about shooting things up and there are neither monsters nor radioactivity.