MikeB:
I had a somewhat similar discussion in here with regard to main memory
Here it is:
I will give you an example, the c64 had 64k of memory. That's a limitation for the amount of game engine, graphics & sound data you could produce if you loaded the game in one go as was usually the case during the system's early stages (lenghty tape loads). Later games broke up the game loading for the various levels, so they allowed for 64k max per level, you can look at games like Turrican 2 or Creatures 2 to see this approach allows for far more complex and diverse graphics and sound.
Now streaming is more advanced than that, you free up unneeded memory (previous areas, enemies, sounds, and such) and load new data into memory while actually playing the level. Resistance & Motorstorm for example performed music streaming, but loaded all the graphics data for the level into memory in one go, in this regard Ratchet and Clank: TOD is more advanced as the game also streams texture data.
Maybe now you understand the relationship between, system memory and storage memory with regard to streaming possibilities. You simply don't need to keep all that data in memory at once, thus a couple of hundred megabytes of combined system RAM is sufficient if take advantage of the PS3 hardware, the system has more than enough bandwidth, processing power and data storage capacity to take advantage of.
To Devs: Although multi-platform PS3/360 games will never get to most out of the PS3, there are still ways to distinguish the PS3 version:
MikeB wrote:
XBox 360 / PS3 mutliplatform games are unlikely to ever push the PS3 to the max, as they will most often likely to stick to 5.1 audio, not use the harddrive, keep the amount of data to fit on a DVD as well, not use to much of the SPE processing potential to keep the game portable tot the XBox 360, not make too much use of the Sixaxis, etc. So many potential sacrifices are likely to be made.
To clarify with regard to the potential sacrifices, some sacrifices would rather relate to additional production costs than real problems relating to cross platform developement:
- With regard to 7.1 audio it should be no problem to create 7.1 audio for the PS3 version and downgrade the quality to 5.1 audio for the XBox 360.
- With regard to harddrive usage, you could use this but you would still have to worry about the game core running well enough on the XBox 360 core. Thus you cannot make your game dependent on this approach.
- With regard to Blu-Ray you can add additional levels and such, but the same issues arrise as with regard to the harddrive. If you break up your game using multiple DVDs publishers will have to take into account additional costs, probably mainly relating to game design, you will have to adapt the game and probably duplicate much of the game on the discs to create a more seamless user experience and prevent too much disc swapping. This is less an issue with highly linear games but for a game like God of War 2 which would take up at least 14 CDs (instead of 1 DVD) this would be very annoying, likewise as with other games which allow you to revisit prior locations. For games more non-linear games like GTA and OBlivion this will present to be a problem.
- With regard to SPE processing power, it would be easily possible to create additional effects for the PS3 version, but you will have to take into account some things, like in Heavenly Sword you have thousands of enemies on screen at once and to recreate this on the XBox 360 would be problematic. So this more relates to game complexity rather just added bells and whistles.
- With regard to Sixaxis usage, you will have to worry about this functionality being playable well enough with an analog stick as well. For example in R&C: TOD you can control ratchet while simultaneously controlling tornados as well as being able to move the camera position, such an approach wouldn't be an option.
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