Repositioning the camera was only the start - Rockstar North has made many changes to the game to make the first-person view more authentic.
"You have to change pretty much everything," said Nelson.
"We have a very solid third-person animation system, but you don't just put the camera down there and expect to see the guns, aim, and shoot.
"All those animations are new when you switch to first-person, because it all has to be animated to the camera, to make it feel like a proper first-person experience that I think people would expect. All the timings have to be re-evaluated," he added.
"There's stuff that just doesn't exist in third-person: the weapon recoil, the reloads, the weapon switching. All of the weapons have been up-rezzed and animated properly, so the shells come out the right way and have the right muzzle flashes.
"I think we created 3000 animations on weapons alone."
Other details released today include:
* All vehicles have functioning speedometers and gas dials
* Some more expensive vehicles have a radio display that show the radio station and song you're listening to, and your character bobs his head to the music.
* You can duck below the steering wheel if you're being shot at.
* On bikes and helicopters, a helmet or a set of goggles restricts your view and muffles the audio.
* There are a number of control schemes available.
* Aim assist, ragdolling, and the combat roll can be disabled.
* You can toggle whether the game switches to third-person when taking cover or not.
* Selfies are no longer an overlay - you take out your phone and look through the viewfinder.
"This is new territory for us," said Nelson. "We wanted as much as possible to retain a sense of character, whatever character you're playing. Whether that's little fidget or hearing them speak.
"There are things you don't see as well from a different perspective. When we started to play around, we started to see all this stuff we never saw before. It's just a different way of looking at things."
Grand Theft Auto V is out on Xbox One and PlayStation 4 on November 18, and Windows PC on January 27.
- Gameplanet