Bigger than Titanic?

James Cameron famously crowned himself "king of the world" after his epic film Titanic swept the Oscars a decade ago.

But as the director heads to Canada for this weekend's Walk of Fame celebrations, he boasts that his watery 1997 blockbuster starring Leonardo DiCaprio and Kate Winslet pales in comparison to his latest project, Avatar.

"It makes Titanic look like a picnic," Cameron said recently during an interview from Los Angeles, where he is working furiously on the new film.

Even Cameron, 54, finds it hard to describe the hugely ambitious Avatar, which is being made in stereoscopic 3-D and combines live action and computer animation.

"It's simultaneously the most vexing and the most rewarding type of production that I've done yet," Cameron says of the project, due in theatres Dec. 18, 2009.

The scope of Avatar, which reunites Cameron with Aliens star Sigourney Weaver, is perhaps not surprising. After all, the filmmaker, who was born in the mining town of Kapuskasing, Ont., and raised near Niagara Falls, Ont., has pushed the envelope throughout his career.

He burst onto the movie-making scene with the 1984 box-office monster The Terminator, starring Arnold Schwarzenegger and Linda Hamilton, whom Cameron went on to marry and divorce (he's currently married to wife No. 5, Titanic star Suzy Amis).

After the success of The Terminator, Cameron helmed True Lies and The Abyss, all the while developing a reputation as a visionary filmmaker with a legendary temper (Mary Elizabeth Mastrantonio is rumoured to have burst into tears on the set of The Abyss after Cameron suggested extras urinate into their wetsuits to save time).

His domineering presence on the set of Titanic became the stuff of film legend. But after making the biggest box- office success of all time, Cameron turned his attention to documentaries.

"I got involved in 3-D, doing 3-D documentaries, natural history, deep ocean exploration stuff, and at that point I sort of decided I didn't want to go back to non-stereoscopic moviemaking, but then there was a lag time while the theatres didn't exist yet," said Cameron.

"I decided to work on a very large project that would take time to develop properly and design all the elements of the world, to give them time to get the theatres in place. Now the timing seems to be working out quite well. In the meantime, I was having fun doing ocean expeditions."

Avatar, a futuristic thriller about humans battling a race on a distant planet, was written 14 years ago, Cameron says.

A three-month live-action shoot has already been completed in New Zealand and the director is now labouring over the other 60% of the film, using cutting-edge techniques.

Cameron is clearly exhilarated by the challenge.

"It's this form of pure creation where ... if you want to move a tree or a mountain or the sky or change the time of day, you have complete control over the elements and the production design," he said.

As for the Walk of Fame ceremonies, where Cameron will be recognized in Toronto on Saturday alongside fellow Canucks including Michael J. Fox, k.d. lang and Bryan Adams, the man with a shelf full of Oscars says the accolade means a lot.

"It's not old hat because it's 'small-town boy makes good, gets to come back to his old neighbourhood.'

"It's not the same as getting an accolade anywhere else."

"I enjoy the fact that this is taking place in Canada. ... Getting some acknowledgment back home is always a sweet thing, and don't let anybody tell you different."