Ironsight Transitions

After spending a bit of time looking at CoD 4's ironsights in the context of single player, I started to pay more attention to the actual transition.



They make a few changes between their From the Hip position to their Aiming Down Sights position.

1. Animate raising/lowering the gun to the player
2. Change the field of view, but blend that change over time
   
3. Increase the depth of field blur on the parts of the gun closer to the player

What I really found interesting was the order in which all these changes happen. You can see in the video above, that the animation begins ever so slightly before the field of view change.

I think this is a direct result of IW spending a lot of time watching soldier rifle their weapon. Obviously, a solider wouldn't start focusing their vision until the weapon is in their line of sight.

Of course, everything blends linearly between the two positions. The blur is applied gradually. The field of view adjusts throughout the transition. The bullet deviation, represented by the crosshair, gradually decreases/increases while the crosshair fades in/out.

Nailing this transition is critical. I once read that Miyamoto told Retro Studios that if they didn't nail the transition between the ball and first-person in Metroid Prime, then they couldn't do the game. Transitions are key to keeping the player immersed at all times.

If the player believes the transition, they'll believe the entire experience.