New PSM - New PSP info

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Originally Posted by Ammadeau

It's not the same amount of polys. What tesselation does is multiply the amount of polys in a model to smooth out its edges. It could be that the devs make a low poly model in the game on the left and the PSP tesselates that model on the fly. So it limits devs to some degree (since they'll have to make models that tesselate well), but it'll allow the PSP to display more polys than it would be able to otherwise.

Or so I'm guessing from the limited info.

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How can you scale polys out to make it tesselate well? Do they just render it out and see what the hell's going to happen? Must be a time consuming process. Although I'm sure once the algorithms are down it wouldn't be too hard to cope.

Like texturing... it looks like a pain in the ass and is, but once you get the hang of it you've.... well... got the hang of it.

Tesselation is pretty cool, it was first used in computer graphics by Pixar in Geri's game. Basically, you give the engine a polygon net and an iteration number, plus a few rules on edges(smooth or crease) and it basically divides the polys and shows them to you. It is fairly tough to get working in real time, and what Sony have done is that the iteration number changes with the camera distance. If the camera is far from the object, the oblect's iteration number is 0 or small. As the camera gets closer, more iterations are required. This cuts down on the storage of polys, because you no longer need a hi-res model, you could just use real time tesselation. Bottom line, I'm excited. :)

Ammadeu: It doesn't limit the artists who develop models at all. All they need to do is create the model using nurbs instead of polygons and then the poly net is automatically generated from the nurbs surface.

So as long as your models aren't going to be huge anyway, it saves you processor power in the end?

This is interesting. I'm going to be going to school to learn all about animation in the near future...

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Originally Posted by Andrew

So as long as your models aren't going to be huge anyway, it saves you processor power in the end?

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Yes, as long as you shift the burden of tesselation to a graphics core(processor), you're not bothering the CPU at all. In fact, in graphics programming, you can send Vertex data directly to the GPU using OpenGL or Direct3D.

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Originally Posted by seen

Ammadeu: It doesn't limit the artists who develop models at all. All they need to do is create the model using nurbs instead of polygons and then the poly net is automatically generated from the nurbs surface.

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It makes it kind of impossible to do fine details since everything is going to get smoothed out. I know from my own experience I would have to tweak a model after tesselating it to get the results I wanted. I could never get it just right from just altering the base model. But it's the kind of detail that wouldn't matter for a screen the size of a PSP so it's a moot point. :p

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Originally Posted by Andrew

So as long as your models aren't going to be huge anyway, it saves you processor power in the end?

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The whole benefit of hardware based tesselation is to take the proccessing burden away from the main cpu. As far as the CPU is concerned, there's no difference for it dealing with the tesslated and non-tesselated models.

Actually the hardware tesselation was added so the psx ports didn't look much worse than the games made from scratch for it. Though what is more important is how it is used. I mean if it makes any model no matter where they are to that, it would be a waste of power.

As for how it works, it does it by what devs tell it to do. Most devs who start from scratch won't bother with it however devs would be nuts not to use it in thir psx ports.

so sony is bassicaly doing real time subd surfaces

and it doesnt limit the modeler they just need to plan out the model better putting edges and vertex's in key spots on the low res model so it smooths nicely

ive played with SubDs in maya a bit havent gotten serious with them

Great, now all the games will look like cheesy 1997 PSX/Saturn FMVs!

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Originally Posted by Damian79

Actually the hardware tesselation was added so the psx ports didn't look much worse than the games made from scratch for it. Though what is more important is how it is used. I mean if it makes any model no matter where they are to that, it would be a waste of power.

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Not quite that easy. You can't just plug a PSX game into this and expect a shiny improved result. You have to tell the PSP how to tesselate each face of every model, because of course you don't want it to do it to edges that are meant to be sharp and since it smoothes out surfaces they also tend to lose their definition. Yeah, I'd still expect PSX ports for this on the level that GBA gets SNES ones, but there's still going to be work involved for the developers to get it working.

What's more likely is PSX games will be ported as is and make little to no use of this feature. Think about Capcom's RE ports. They could have added more polys to the figures by tesselating the models beforehand that the more powerful systems could handle, but they didn't bother.

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Originally Posted by Ammadeau

Not quite that easy. You can't just plug a PSX game into this and expect a shiny improved result. You have to tell the PSP how to tesselate each face of every model, because of course you don't want it to do it to edges that are meant to be sharp and since it smoothes out surfaces they also tend to lose their definition. Yeah, I'd still expect PSX ports for this on the level that GBA gets SNES ones, but there's still going to be work involved for the developers to get it working.

What's more likely is PSX games will be ported as is and make little to no use of this feature. Think about Capcom's RE ports. They could have added more polys to the figures by tesselating the models beforehand that the more powerful systems could handle, but they didn't bother.

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Good point, while did mention additional work on the devs part, the need for better graphics than the psx probably isn't there on such a small screen.