Interview: Naughty Dog on Uncharted 2

Uncharted 2 is scheduled for release later this year exclusively on Playstation 3. For more information read our recent article on the game.

1. Please tell us about the inspiration for the Drake series and the sequel in particular?

When thinking about what to do with our next series, we narrowed down all our crazy game ideas and decided to stick with what we knew best, which was the action-adventure genre. But we wanted utilize the power of the PS3 to bring a level of cinematic immersion never before seen in a video game. With all of this new found power we would be able to tell a really engaging story, create compelling and believable characters and place them in exciting predicaments, just like the best summer blockbusters do. And one of the most important aspects to the Uncharted series is also what serves as the starting point and inspiration for the stories we tell in each game - a historical mystery.

Drake's new adventure is about an unsolved mystery surrounding Marco Polo and his doomed voyage home from China in 1292. After spending almost twenty years in the court of the emperor Kublai Khan, Marco Polo departed with fourteen ships and over 600 passengers and crew - but when he arrived at his destination a year and a half later, only one ship remained, and only eighteen of the passengers had survived. Although Marco Polo described almost every other aspect of his journeys in minute detail, he never revealed what happened to the ships that were lost.

So Drake, attracted by the potential treasure to be found and inspired by the intrigue around this historical mystery, embarks on a quest to find Marco Polo's lost fleet. But he soon discovers that Marco Polo was hiding a much greater secret - he had gone on a secret expedition on behalf of the emperor to find the mythical kingdom of Shambhala (otherwise known as Shangri-La) and to recover the legendary Cintamani Stone, the "wish-fulfilling jewel" of Buddhist mythology. The stone is described by Marco Polo as a massive raw sapphire which, if it truly exists, would be worth billions of dollars today. These discoveries set Drake on a new course, following Marco Polo's 700-year-old trail through a diverse range of exotic environments to find out if the lost city of Shambhala, rumored to lie deep in the Himalayas, really exists.

2. What movies or literature inspired you, and would it be correct to say that Drake is more Jack Colton (Romancing the Stone) than Indiana Jones?

Everyone at Naughty Dog draws upon a wide variety of personal and professional influences to inspire their work as we've developed the Uncharted franchise. It could be anything from films, books, other games or anything else. It's important to us and our process to have all these different influences, because we never know where a brilliant idea will come from. Even if it's on a subconscious level, all the media that we've consumed has had some influence on all of our games.

Another reason why things may look and feel familiar is that we wanted to leverage what we call the "comfort food" feeling of the action-adventure movie genre and translate that into a fun and satisfying experience when you play our games. This "comfort food" feeling comes from elements of movies that we have all grown up loving and often associate with specific genres - if one were to make a sci-fi game or a horror game, there are certain tropes or hallmarks of the genre that a developer will likely reference in one way or another.

We also had this notion of "comfort food" when we were creating the character of Nathan Drake. We knew we wanted to create a character with a deep backstory and some intriguing complexities to his personality. We also knew that we wanted Uncharted to be a franchise and not just a one off so that we can continue to expose that depth and complexity over the course of several games!

3. How difficult was it going from the Jak series to something completely different in the form of Uncharted, and why did you make the choice?

At the time we wanted to believe that the transition would be fairly easy between Jak and Daxter and Uncharted because the core of both series were the same - story-driven third-person action-adventure games. Of course, it was really not that simple since we were dealing with brand new, significantly more powerful hardware with the Playstation 3.

The fact that we had this exciting new hardware platform with so much potential was one of the main reasons we looked to start something new and different in the first place. The graphic fidelity offered by previous generations of PlayStation hardware was pretty limited, so we felt compelled to keep our games within the realm of fantasy. The PS3 was the first hardware that gave us the confidence to tackle the real world and human characters. And that decision forced us to develop a brand new set of skills in just about every discipline. From writing and game design, to modeling and lighting, every employee at Naughty Dog had to step up their game and learn something new. But we're really happy with what we were able to accomplish and now we feel more prepared to tackle any type of game we might consider in the future. Of course the immediate task at hand is to once again raise our own personal bar with Uncharted 2: Among Thieves.

4. What decisions during planning did you make to secure that Uncharted wouldn't be seen as "just another Tomb Raider clone"?

We weren't concerned with any potential comparisons to other games when we started working the Uncharted series and it would be detrimental to our development process to let it distract us. From day one our focus has been in combining compelling narrative and engaging gameplay to create a game that is much more than the sum of its parts. Our goal has been in creating just the right feeling throughout our game using all of the tools and tricks we have available - a feeling of experiencing an action-packed blockbuster movie that just sucks you in until it's over and then leaves you wanting more. There's also something about the way in which the narrative draws you into the characters and the challenges that they're facing that separates the Uncharted games from most of the other action-adventure titles out there. We really are trying to tell a more sophisticated and emotionally engaging story than what you've traditionally come to expect from a videogame. From the anecdotal feedback that we've read on the blogs and in the forums it seems like a lot of people only really appreciate how much this matters after having played the game.

5. What is the most radical difference between the first game and the sequel, and how have you made sure that fans of the first game will also enjoy the follow-up?

One of the main differences is the addition our action-stealth mechanic, which is all about adding complexity, expanding player choice in our combat situations, and fleshing out our enemy AI system. "Action" represents the idea that we're trying to keep the pace up and "stealth" represents the tactics we're familiar with regarding taking out enemies unnoticed. We don't want to introduce the frustration of being forced to move at the game's (presumably slower) pace by replaying and replaying a set-up due to failing a stealth-heavy situation.

Providing the option of action-stealth allows the player the choice to get more invested in the set-ups, getting to know more about the environments than a straight gunfight would allow. It also allows us to embed more narrative and story into the gameplay. By showing what enemies are doing before you're engaged in combat and by overhearing some background conversations, you'll be able to see more of the story in context to the environment or situation. It also reinforces the story needs by allowing us to make set-ups more appropriate to the tone of the story. Is Drake infiltrating an area? Are the enemies already in defensive positions? Whatever the story needs, we can have the enemies parallel that feeling now.

As a result of expanding our gameplay to account for action-stealth, we've changed up the dynamics of how a player approaches a combat situation by adding new behaviors to enemies: an investigate behavior and a hunting behavior. With the investigate behavior, the enemies have peripheral vision just like humans. When Drake enters this peripheral vision the enemies will look over in the direction they think they saw him, and depending on how long he was in this vision cone, they may just dismiss what they saw or they may walk over and check out the area Drake stood in. The hunt behavior is triggered when the enemies have already spotted Drake and are engaged in combat with him. While in combat the enemies make certain assumptions on where Drake is, based on his last known location. If they lose sight of Drake for a few seconds, they will start hunting around the area, starting with his last known location, and then spread their search out if he's not found. Our battles can be switched up from straightforward gun fights to an action-stealth battle midway through, picking off each enemy one by one as they separate in their hunt for Drake.

This just further reinforces our focus on creating player choice in Uncharted 2 and "choice" is the other key word here. We've implemented the new action-stealth mechanics with the knowledge that not everyone likes stealth game play. We think it's fun and it adds a lot to our ability to reinforce the story, but you should play the way you want, even if that means just going in guns blazing. We're just giving the player more options to play the setups however they like.

6. The technology in Naughty Dog games have always pushed the technology, a trend continued by Uncharted. What improvements have you made in the sequel, and how have you pushed the technology further?

Naughty Dog has a fifteen-year tradition of pushing the PlayStation hardware to its limits, and Uncharted 2 sees us setting new gold standards in limit-pushing! After we shipped Uncharted: Drake's Fortune we gave our programmers some time to freely explore any aspect of our engine or the hardware that they were interested in. Everybody immediately got down to business, tweaking the code and adding new features to our engine. As a result, we've been able to squeeze out a lot more of the power out of the Playstation 3, by optimizing our SPU code and parceling out more jobs to the SPUs in general.

With Uncharted 2, the Naughty Dog Engine 2.0 simply allows us to do more, do it better and do it faster. For example, we can display more polygons on screen than we could in Uncharted, allowing us to create environments with even more detail than the last game, and we've increased the number of enemies that Drake can fight at once. Our lighting and shadowing systems have been overhauled. We've revamped the way we render our skies to include much more realistic light effects and a procedural layer of cloud cover.

Also, we're really going for it with the rendering of the snow in Uncharted 2, just like we did with water in the first game - if Naughty Dog is going to do snow, it's got to be the best snow that you've ever seen in a videogame! So we've added shaders for ice, frost and snow that include simulated sub-surface scattering, to really capture the subtle way that light scatters through frozen water.

As if that wasn't enough, we're taking on fur and cloth this time. Our animations are more fluid and even more complex. The AI systems have been vastly expanded. The list goes on and on.

7. Is there any other genres you would like to give a try in the future?

You know, the future is just rife with all sorts of possibilities of every kind imaginable... but we're too intensely focused on finishing this game to start daydreaming right now!