OpenGL Headline News
Volumetric rendering of smoke and steam for the movie “The Polar Express” uses OpenGL API hardware a
CGW features an article on the making of the movie “The Polar Express”. While naturally the entire film used OpenGL API based software and hardware, the story in particular mentions that for smoke and steam, as well as atmospherics and cracking ice, the effect department used Houdini with a new custom tool called SPLAT (Sony Pictures Layered Art Technology). “SPLAT uses a painter’s algorithm to draw all of our smoke and steam,” says Bredow. “It sorts the particles from back to front, draws the back one first and the next one on top of that.” Because the algorithm is accelerated in hardware (Nvidia cards using OpenGL), volumetric renders that might have taken 20 hours were output in three to four minutes per frame. “The nice thing is that an artist can move lights around almost in real time and see the effect on the smoke,” he says.