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[Panajev2001a]

http://ps2dev.org/files/ps2_normalmapping.pdf

3 passes would means that with bi-linear filtering you still have 300 MPixels/s to play with for the rest of the graphics: not okay for full-scene normal mapping and HUGE distances with normal mapping everywhere, btu good for characters and some obejcts here and there.

It would be good for a DOOM 3 port on PlayStation 2 if we could find the kind of guys like the ones that ported Quake II on PSOne.


Thank the main programmer at IOI for this gem.

 

[Nerevar]

Are you saying they do 3 rendering passes in 1 cycle?

 

[Lord Error]

So they are doing a two pass normal mapping? It looks pretty damn good actually, differences from the more complex four pass method are quite small. So small in fact that I'd say it's simply not worth it using the four pass method. Yeah, one extra pass for the base texture and you've got full blown normal mapped model.

I am just not sure if you can do specular normal map in two passes - the only one they show is diffuse one.

 

[ourumov]

Hmmmm...Interesting...Pana we have to talk about this .

 

[OG_Original Gamer]

I didn't read all of the pdf, so would this done through hardware and not software?

If so, then I can't wait to see Riddick on the PS2 if they can get a port approval.

 

[Fafalada]

I am just not sure if you can do specular normal map in two passes - the only one they show is diffuse one.

They show the non-trivial parts of what should be done for specular, the part you're missing is supposed to be obvious (well it IS a technical doc you know)

Anyway to explain - on pixel level -

Diffuse comes down to "dotproduct( n, l )" per light
Specular comes down to "power( dotproduct( n, h ), specfactor )" per light.

The power function can be done as postprocess along with the other framebuffer processing you already do, so what you're left with is still just 2 passes for the dotproduct.

Obviously, diffuse + specular = 4 passes.

 

[Panajev2001a]

4 Passes is not too too bad... Yes, you are left with 150 MPixels/s which is not much, but obviously this figure is misleading: I am assuming that I want to do specular+diffuse normal mapping on every pixel on screen included occluded ones. In the scenes for a game like DOOM III we could cheat here and there: use diffuse normal mapping most of the times we do normal mapping and only enable the specullar version once a character comes close to the screen and there are not many characters in the room...

There are situations in which this technique can be useful IMHO.

It depends on what you are giving up: in Silent Hill 3 we had very detailed characters, awesome lighting and shadowing (soft shadows too) even without normal-mapping.

The option is out there though.

 

[Fafalada]

No need to think of it in terms of MPixels Pana, in the end it just matters how fast the scene renders in cycles Anyway a corridor shooter like Doom3 has rather low overdraw (before you start accounting for shadow rendering) so chances are pixel processing wouldn't be your biggest problem - as long as you keep the number of lights reasonable.
Consider that XBox version has significantly lower number of shadow casting lights too (I suspect that's thanks to CPU limitations though).

It depends on what you are giving up: in Silent Hill 3 we had very detailed characters, awesome lighting and shadowing (soft shadows too) even without normal-mapping.

Well personally I found SH3 characters a hell of a lot better looking then Doom3 ones.
If anything in SH3 would benefit from being per pixel (without degrading what is already there), it'd be the flashlight/environment lighting.
Of course you shouldn't forget that you need to sacrifice more memory for the normal maps - and that will always come at expense of something else.

 

[Panajev2001a]

I think DOOM III can be ported to PlayStation 2 and look nice enough.

 

[mrklaw]

I think DOOM III can be ported to PlayStation 3 and look nice enough.

do you mean PS2?

 

[pcostabel]

I think DOOM III can be ported to PlayStation 3 and look nice enough.

So Playstation 3 automatically converts bad art into good art?

 

[dark10x]

I think DOOM III can be ported to PlayStation 3 and look nice enough.

To PS3?! I'd hope that PS3 can handle visuals WELL beyond what you see in Doom 3.

 

[Panajev2001a]

Typo guys... typo.... I meant PlayStation 2 .