Presentation from GDC 2009 that describes some of the audio technology and process that we shipped in SOCOM: Confrontation

2. Introduction
Who are we?
Paul Martin
– Started out in the industry 1996 as PlayStation programmer
– Currently a technical director and one of the principals of Slant Six Games
– Special interest areas; data pipelines, technical management, graphics
rendering, special effects
– Technical lead for SOCOM: Confrontation
Ken Felton
– Entered the game audio world in 1994 from Film/TV/Music business.
– Currently Sound Design Manager at Sony Computer Entertainment
America- Foster City, CA
– Special interest areas; Remote recording, run time audio DSP
– Audio content manager for SOCOM: Confrontation

3. Introduction
This talk?
• Audio development for SOCOM: Confrontation
• Challenges
• Solutions
• Collaboration between SCEA & Slant Six
• Surprises

4. SOCOM: Confrontation
Features / Specs:
• 32-player simultaneous online multi-player
• Extensive online community support
• Third-person, tactical shooter genre
• Online only
• Up to 32-player simultaneous multiplayer
- 4 vs 4, 8 vs 8, 16 vs 16
• Up to 35 on-screen characters (32 + 3 AI)
• Large rich environments
• 7 game modes
• 3-D audio
• Voice chat
•1st title to ship with PlayStation™ Headset

5. Audio Technology
• Audio emitters: Any audio source
– Static (e.g. environmental audio)
– Dynamic (e.g. character interactions)
• Virtual Emitters: Emitter proxy for
occluded/indirect audio path network
• Virtual Emitter network: Defines pathways
between Virtual Emitters

6. Virtual Emitters

7. Virtual Emitters
SOCOM: Confrontation
Crossroads Level: Virtual Emitter Network

8. Virtual Emitters

9. Audio Occlusion
• Problem:
– Audio filtering due to occlusion can be extremely
expensive
• Many ray casts!
– Large PPU cost on PS3
• Solutions:
– Virtual Emitters
– Careful placement of virtual emitters
– Batch ray casts & process on SPU
• Latency not frame-critical for audio –can wait for results
– Optimize code!

10. Audio Occlusion
• Takeaway-
– Can be extremely expensive to implement well
– Sounds incredible if you do it right
– Use virtual emitters!
– Optimize your ray casts
– Use SPU if available!

11. Audio for Physics Objects
• Problem:
– Audio simulation of real-time physics objects
• E.g. rolling or bouncing objects
• Settling sounds
• Audio can be triggered frequently
• Strategic gameplay considerations
• Solutions:
– Count collision contact/exit points
• Can determine rules based on this for bouncing vs rolling
• Tunable parameters per object
– Priority-based audio
– Batch similar emitters based on locality

12. Audio for Physics Objects
• Takeaway-
– Priority-based approach (critical vs non-critical audio)
– Priority for gameplay always wins
– Can get expensive in a hurry – code smart
– Exploit locality of audio sources

13. Audio Build Iteration Times
• Problem:
– Very long iteration times between builds makes sound
design/content editing difficult, and progress hard to
evaluate. e.g. 4 wks w/o new build during summer ‘08.
• Solutions:
– Careful tracking of delivery items using project
management software so we don’t lose track of what has
been delivered.
– Bi-weekly conference calls with sound, dialog, music, and
developer/production staff to discuss progress and any
changes to design or schedule.
– Recruiting additional sound designers to play builds and
regress implementation of delivered sounds.

14. Audio Build Iteration Times
• Takeaway- Offsite sound support services will
be dependant on the game developer for
implementation of assets. The sound team’s
job is not complete until the assets work well
in the game and production signs off. Shorter
iteration loops make a better sounding game.
Sound teams should discuss build delivery
schedules in pre-production and have a back-
up plan for making progress even without
updated, regular builds.

15. Sound RAM reductions
• Problem:
– Sound RAM was cut by 50% of its original size. A
significant SRAM cut after the Beta Milestone.
• Solutions:
– Streaming of all character grunts/dies/etc. We saved
~2MB of Sound RAM
– Streaming of helicopter extraction sequences.
– Streaming of scripted sequences when possible
– Man weeks of careful review of all SFX samples in the
game- delete, down sample, trim, etc.

16. Audio Memory Budgets

17. Sound RAM Reductions
• Takeaway- Plan for worst possible case RAM
scenario – Sony Sound would have leveraged
our streaming grain feature far more, and
designed the sound scape very differently, if
we had any idea that our final sound RAM cap
would end up at 50% of the original budget.

18. Talk to Us
Ken Felton: ken_felton@playstation.sony.com
Paul Martin: paul@slantsixgames.com

19. Q&A
Any questions?