image copyrightGetty Imagesimage captionRobert Downey Sr and Jr in 2008

Film-maker and actor Robert Downey Sr – the father of actor Robert Downey Jr – has died at the age of 85.

"Dad passed peacefully in his sleep after years of enduring the ravages of Parkinson's," the Iron Man star wrote.

"He was a true maverick filmmaker, and remained remarkably optimistic throughout."

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Downey Sr was a leading figure in independent US cinema in the 1950s and 60s, best known for writing and directing the 1969 satire Putney Swope.

He also appeared in such movies as Boogie Nights, Magnolia and To Live and Die in LA.

The movies he created had small budgets, a counter-cultural ethos and cutting humour. Putney Swope was a satire on the advertising world of Madison Avenue, while his other directing credits included 1961's Balls Bluff, 1964's Babo 73 and 1972's Greaser's Palace.

image copyrightGetty Imagesimage captionDowney Sr was said to have "paved the way for a generation of filmmakers to come"

Putney Swope was described by the New York Times film critic as "funny, sophomoric, brilliant, obscene, disjointed, marvellous, unintelligible and relevant". However, the New York Daily News called it "the most offensive picture I've ever seen".

It became a cult classic and was inducted into the National Film Registry of the US Library of Congress in 2016.

In the book Film Talk: Directors At Work, film scholar Wheeler Winston Dixon said Putney Swope and Greaser's Palace "paved the way for a generation of filmmakers to come".

He wrote: "Downey's films during that era were strictly take-no-prisoners affairs, with minimal budgets and outrageous satire, effectively pushing forward the countercultural agenda of the day and bitingly showcasing the inherent hypocrisy of human interaction."

'Hollywood is horrible'

The life-long New Yorker's most recent appearance as an actor was 2011's Tower Heist, which also starred Eddie Murphy, Ben Stiller and Casey Affleck.

As director, his final projects were 1997's Hugo Pool and the 2005 documentary Rittenhouse Square.

He tried to keep his personal life out of limelight. But in 2001 when his Oscar-nominated son was facing cocaine charges, Downey Sr spoke to the New York Post about the difficulties of being part of the film business.

"Life is too easy when you're a movie star. People will do anything you want and get you anything you want," he said. "Hollywood is a horrible place."

Downey Sr was married three times. His first wife was actress Elsie Anne Downey and they had two children – Allyson Downey and Robert Downey Jr. He went on to marry actress Laura Ernst, and his third wife was Rosemary Rogers, the best-selling author.

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