GCN´s flicker filter and texturing...
- Thread starter Almasy
- Start date
Panajev2001a
Veteran
detail texturing does not "generally" increase sharpness... look at Halo's walls and rocks... it adds a sort of roughness/3D detail that gets progressively less and less translucent as you get closer ( to simulate what happens in real life: you get closer and you basically see more detail as the "big" patterns are broken in their components... )...
What you probably experience in The Getaway is again due to mip-mapping ( I think The Getaway uses mip-mapping ): in that moment you described you probably passed from one mip-map level to a more detailed level ( maybe you went from level 1 to level 0 which is the highest resolution one )...
What you probably experience in The Getaway is again due to mip-mapping ( I think The Getaway uses mip-mapping ): in that moment you described you probably passed from one mip-map level to a more detailed level ( maybe you went from level 1 to level 0 which is the highest resolution one )...
Panajev2001a
Veteran
Ug Lee said:
Bingo
Steve Dave Part Deux
Newcomer
Panajev:
Would a 3-line filter provide 3 samples per-pixel on output?
Would a 3-line filter provide 3 samples per-pixel on output?
Panajev2001a
Veteran
If you take 3 scanlines and you blend them together then you get 3 samples per pixel...
Steve Dave Part Deux
Newcomer
Cool, thanks for your help.
Blade said:
Okay, but why?
Tagrineth said:
clem64 said:
I hardly think that it’s memory limitations holding PS2 back from doing detail textures.
What I regard as detail textures, are small, high-resolution 8 bit or 4 bit monochrome textures, with alpha for fade in out and blending.
I don’t think S3TC would do much good on such a texture, as there wouldn’t be much bit reduction to be done. S3TC has big limitations with alphablending to.
marconelly! said:
The metallic tower has detail textures? That’s not very detailed
, what’s more I can’t see more than two layers: base and reflection.It has been some time since I played Legend of Black Kat, but I seem to remember that the grass looked more like fur shading or voxels to me.
When I think of detail texturing I’m thinking about a heavily tiled map with indistinguishable, or almost indistinguishable texels.
I think what might be perceived by some people as detail textures, really is just mipmapping doing its thing.
When you think about, it really is a little difficult to se the exact boundary between the two techniques...
marconelly!
Veteran
If you are not really close to the the tower, there are reflection and base texture. Get close to it and you will see that additional layer of more detailed texturing kicks in over that. My impression is that textures don't necessairly have to be ultra detailed to call that effect detailed texturing. They just have to be more detailed than normal when you get really close to the object. Maybe it's just mip-mapping, as you've said it's hard to draw a line between the two.
I'll play the demo version now and get back to you.
*edit* You are right. It indeed is some kind of volumetric effect, and is pretty damn nice at that. I wish more games utilized it. Still, it behaves like detailed textures would, I guess. It's detailed close to you, and gets faded the further you look.
I was thinking, does the EE have special hardware for down filtering textures for use in mipmaps, or is that operation so simple it would be wasting space to have specialized hardware for it?
The reason I’m asking is of course because it would be very beneficial to reduce textures to the needed size before sending them over the EE to GS bus (I’m thinking realtime filtering because with only 32Mb, storing all mip levels in memory would be a definite no-no). This would make perfect sense since, if I remember correctly, GS mipmap hardware performance takes a hit “shrinking†textures but not to “enlarge†them.
The reason I’m asking is of course because it would be very beneficial to reduce textures to the needed size before sending them over the EE to GS bus (I’m thinking realtime filtering because with only 32Mb, storing all mip levels in memory would be a definite no-no). This would make perfect sense since, if I remember correctly, GS mipmap hardware performance takes a hit “shrinking†textures but not to “enlarge†them.
Squeak said:
The most common way to down filter for mipmaps is, AFAIK, simply averaging together 4 pixels at a time. Really easy to do on 16 and 32 bit textures, not so easy with CLUT textures (...if you want it to still be a CLUT texture after the scaling). I’ve never heard about the EE having dedicated HW for it.
Yeah, I think that’s pretty common, only sending as large mipmaps as needed over the bus.
Storing all the mipmap levels in memory adds 33% to the texture size. Not an insignificant amount, but I would not call it a big no-no. If the largest mipmap size you needed was 16x16 and you were to make that by reading in and scaling down a 256x256 texture you would waste huge amounts of main memory bandwidth. That I would call a big no-no. I guess you could make a compromise and only storing every other mipmap level, and generating the rest. That would only add 6.67% to the memory footprint.
I think that depends on how much it shrinks them. Not using any mipmaps at all invokes a large performance hit, AFAIK.
Eh, I'm kind of more partial to detail maps that actually give an impression of intended material rather then just overly sharp noise maps that usually end up looking the same on everything, and not particularly good either. (Serious Sam or Alice particularly stuck in my memory as example of this).Squeak said:
Either way, I'm pretty sure J&D uses detail maps on terrain (as did Drakkan for that matter, and probably a few others) at the very least - it's something that goes hand in hand with typical terrain generation methods anyhow.
Anyway, you're right about it not being a memory problem.
Detail mapping is one of those things that just fit very nicely on VUs, including stuff that can't be done efficiently on other hw like drawing only relevant detail layers as dictated by distance etc.
However...
if you're not already using finely tesselated geometry, you stand a good chance of running into precision problems with UVs on GS(which can result in swimming texture artifacts and worse), so you face forcing your artists to tesselate low poly stuff (say, walls) by hand or complicate your shaders by including automatic subdivision as required... neither of which is particularly desired.
Although it's also true that above kinda fits with GS just generally liking small polygons much better then big ones anyhow... - but it doesn't change the fact that it's an annoying thing
Afaik it's possible to get different resolution maps from IPU. Haven't really fiddled with that though.
Although realtime filtering would be nicer if it were free... I can't say I ever saw the memory overhead as much of an issue, given the benefits.
Those GS performance hits are in relation to normal drawing. When dealing with drawing a rectangle with fixed coordinates, it's relatively easy to do this without the performance hits too.
But even so it takes drawing time - so if you can really afford it, using some compression scheme on GS instead should work better I think.
Okay, I didn’t mean that heavily tiled, I meant something along the lines of, like in Toejam & Earl 3 or Halo, when you look down and see some blades of grass, then walk half a meter and see the exact same blades of grass.
Jak & Daxters grass, isn’t so detailed that you can make out individual blades of grass (though it has some very high resolution textures on some of the brick houses in the village, on the Precursor ruins on the beach and in some other places that could be detail textures), and it isn’t only the high frequency monochrome detail that’s added as you get closer, in J&D. Of course it could be called detail textures anyway.
But to sum my question up, do you think Halo like detail textures is possible on PS2?
Well J&D among other things isn't really styled towards sharp look - their textures are handdrawn, so it's different kind of detail even before we talk resulotion. And well, yeah, landscape models often play with detail textures up close that are full color maps, not just b&w gradients.
I don't see why not. The only real technical issue you face is dealing with UV precision - which shouldn't be a problem if you've thought of using this from the start. (it would make it a bitch to add it in the last moment though).
Fafalada said:
tjhats what i thought but it just isn't happening.... i would love to see *halo-like* razor shard detail textures on PS2.... they would really add soooo much to some games..
