Before the footage was shown director Fede Alvarez insisted that hardly any of the images were computer generated. That description below comes courtesy of io9.com.
First, we saw the iconic cabin, which is introduced with the iconic Sam Raimi low-angle tracking shot. A group of new kids and Jane Levy push open the old cabin door, revealing leaves, dirt and a grubby cabin floor. Jane looks beat as hell and ready for her night of heroin withdraw (yes they are keeping the plot similar to the original). A trap door is discovered. A boy heads down the stairs and discovers THE NECRONOMICON! Sadly, we didn’t get the money shot of the new book cover; all we saw was a book wrapped in black plastic, someone ripping into it and the familiar old pages. The character starts flipping through the Necronomicon, rubbing a pencil over the strange words. He recites the enchanted phrases. Jane lets out an insane high-pitched scream and then states, “We’re all going to die tonight.” This was already cut together pretty quickly; now things get even faster, so we’re only getting flashes of the gore. I spot a girl in the shower cutting up the sides of her mouth, while one of her cabinmates screams, “What are you doing?” Another girl’s arm looks like it’s covered in boils, and she takes an electric carving knife to her bicep. Someone starts up a chainsaw (the crowd goes insane at this). Cut to another girl trapped in the woods, wrapped with branches. Yep, the raping tree is back. Jane returns with white eyes, white skin and a black tongue, which she sticks out, provocatively licking an exposed knife. Slowly the knife starts splitting her tongue in half. She’s doing this right in front the boil armed girl’s face.