While Mark Ruffalo was in town recently to be honored by the Gene Siskel Film Center, the two-time Oscar nominee sat down at the Ritz Carlton Hotel to chat about “Infinitely Polar Bear,” his new film (opening Friday) that was truly an autobiographical journey for the movie’s director, Maya Forbes.

In the film Ruffalo portrays a character based closely on Forbes’ father, a bipolar man struggling with all kinds of issues back in the 1970s. His wife (played by Zoe Saldana) goes back to school to get her MBA, so the family can improve its financial situation. So, it basically is a story about a bipolar individual raising his two biracial daughters on a very tight budget, with his wife only present on weekend breaks from graduate school.

An added twist: Cameron Stuart (Ruffalo’s character) is from one of the oldest New England families, who trace their wealth back to the time of the Mayflower arriving at Plymouth Rock. However, the family funds are controlled by Cameron’s grandmother, who keeps him on a very limited allowance.

In discussing how he could not really relate to “that kind of wealth, spread over that many generations — where they operate under their own very strict rules,” Ruffalo pointed to one scene in the movie to illustrate the challenges Cameron and his family faced.

“The grandmother wouldn’t consider paying for his daughter’s tuition to private schools, so they wouldn’t have to go to the terrible public school in their neighborhood, telling him, ‘I wouldn’t want to give the girls the wrong impression,’ or spoil them about the value of money.

“But instead she tells him to ‘Take the Bentley,’ a car he cannot even afford to fill with gas! That world is so unreal to me,” said Ruffalo with a laugh.

Because the film was such a personal project for Ruffalo’s director, I asked if that made it more challenging for him.

“It could have been,” said the actor. “It depends on who you’re doing [a film like this] with. I spent a lot of time with Maya before we made it, so I really felt I had a handle on where she wanted to go, and what her dad was all about. I had heard all the stories  about her father. … Anytime I didn’t know where I was going with the role for a scene or whatever, she was right there, of course, and helped me out. I also felt she left me enough space that I could also make it my own as well.”

In the film, Ruffalo’s character is an excellent cook. Turns out that didn’t take a lot of acting on his part. “I’m an OK cook for real. My wife doesn’t cook, so someone’s got to do it!”

As for the repair projects Cameron Stuart is seen doing in the movie, Ruffalo added those also came naturally to him.

“Look, I have three kids. If you’re not tinkering around the house, you’re not spending enough time with your kids. Something is always breaking down or needs to be fixed or needs to be built. So, I’ve learned to become a natural tinkerer.”

As for having the very beautiful Zoe Saldana cast as his wife and doing romantic scenes with her?

“Ah,” said Ruffalo with a sly smile. “Now that’s where my acting skills really came into play. That was SO tough,” he added with a big laugh.