iPhone 3GS: Prepare For a 3D Graphics Shock

Half-Life 2 on PC. The 3GS GPU has all the features required to do this

The new iPhone CPU is getting a lot of buzz, and for sure, it will make the iPhone 3GS more responsive than its predecessors, but I think that most users will be "shocked" to see how powerful the iPhone 3GS is for 3D graphics. Obviously, you have seen the specifications: we're going from a fixed-pipeline graphics architecture to an Open GL 2.0 ES one. But put in simple terms, it's like going from Half Life to Half Life 2.

Half-Life on PC

None of the game demos shown at the WWDC keynote has scratched the surface of what can be done by the iPhone 3GS. We expect (hope that?) the new Doom Resurrection game to come in two versions, one for the iPhone 3GS and another for older iPhones/iPod Touch… let’s wait and see.

Normally, the Power-VR SGX GPU in the iPhone 3GS should be much faster than the old one in two fundamental graphics metrics:

• Triangle setup: This defines how many triangles can be processed per second
• Fillrate: a measure of how many pixels can be modified per second.

Both metrics are key to increase graphics realism. But that's not it: the iPhone 3GS does not just use sheer brute force to make games look better. Thanks to the more programmable architecture of the Power-VR SGX, developers can now use techniques found on PS3 and Xbox 360 games. Here are a few:

Bump Mapping and Normal mapping

Normal map demo on PC

Basically pack details in textures, rather than triangles. This is leaps and bound better than just adding more triangles to add details.

Shadows

Advanced Shadow Mapping demo on PC

You have not seen a lot of shadows on iPhone, right? This is about to change, thanks to techniques like shadow maps or stencil buffer shadows.

Multi-textures and lightmaps

Lightmaps from S.T.A.L.K.E.R on PC

Lightmaps is a basic way to pre-compute a very complex lighting for static objects. Made popular by Quake in the gaming world, it is still a fundamental too that is now available to iPhone 3GS developers.

Conclusion

Beyond the technical jumbo mumbo, the takeaway important is to understand how far forward graphics power on the iPhone has moved. You will be shocked by the second generation of iPhone 3GS titles.