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Blue
02-16-2002, 12:19 PM
Is MAX Payne the wave of the future for realistic textures?

Are photo textures bad news for texture artists?

Anyone have any good stories to tell about having to use photo for textures. Or time wasted making use of bad sources. Or just your opinions pro or con about using photo's.

suck
02-16-2002, 01:03 PM
Here's my take...

Although I voted that photo textures are "good", this comes with a bit of explanation...

As engines become more sophisticated, the role of textures will (and already has begun to) change dramatically. Back in the early days of mainstream real time 3d, the Quake engine presented to us models and worlds that were for the most part statically lit. The characters were shaded entirely based on the color of the floor they were stepping on with no real time light involved.

What this meant for textures is that every lighting component had to be included in the map. High frequency detail like rivets and low frequency detail like the underside of an arm being darker... specular hilights and shadowing... all cooked into the map. While this meant that the model looked good in stills, it severly detracted from it's ability to convince the viewer it was part of a living, dynamic world. In essence, it was floating in space mostly unaffected by its surroundings.

Polycounts were also at a minimum back in those days, so the only thing you could really define with the geometry was profile. Any detail was left to the texture. This paradigm continued for quite a while.

Jump forward to now. Models have gone from averaging 200-400 polygons to 2000-4000. This doesn't just mean smoother forms and the demise of the ever popular "blockhead". :)

Rendering technology has gotten to the point that the geometry of the model is responsible not just for the profile, but also for the low frequency lighting. No longer is it necessary to darken the texture of an arm on its underside to imply the roundness of the form... it is handled in real time through Gouraud shading, in relation to the placement of lights in the scene. If the artist wants to have an extra dial on his control pad, he can model it out and let the engine light it instead of painting it into a texture. Then when Johnny Explosionman runs by and shoots his rocket launcher, the light cast from the weapon will strike that dial and light it appropriately.

Some hardware, like the Xbox and Gamecube, along with the underutilized Geforce3 on the PC side, is capable of handling high frequency lighting in real time... aka bump mapping or per-pixel lighting. Doom3 is going to have normal maps, which are bump maps defined by super-high resolution geometry. In the next couple years we are going to see a true convergance between game and broadcast/film rendering techniques.

So where does this leave photo textures? Let's take Max Payne for example and compare it to Halo. Both titles were released in the same year, on the same hardware... the Xbox. Granted Max Payne was developed for a least common denominator PC platform, but since they are both Xbox titles now it is fair to compare. :)

Max almost exclusively relies on photo texturing, in many cases to great effect. Environments in particular are eerily realistic as the artists have taken great care to use appropriately shaded photo source that matches the scene lighting. The characters on the other hand, while quite pleasing in still shots, suffer once they begin to travel throughout the scene. Their texture details are too stark, too lit to blend in accurately. They are decidedly old-school in their composition... throwing all of the lighting components into the map including specular and low frequency shading. Undoubtedly, the artists were not the ones that made the decisions which led their engine down this path, and given what they had to work with, they made a damn fine looking game.

But it's no Halo.

Halo is the poster child for multipass rendering at this point in time. Each surface in Halo, be it environmental or character, is handled with multiple layers of texture. Most of the time from what i could tell there is a diffuse component, a specular component, and a bump component. Occasionally there is even more than one of each, to simulate layers of grating or animated lights. Textures are never prelit and objects sit in the world flawlessly. If you haven't seen this game, you need to.

Photos play a different role in each title. In Max, they were employed much more literally, straight up. The models don't have a ton of polygons to define the lighting, nor does the renderer have significant multipass ability. So they did the best with what they had and put all of the lighting components into the one map.

Does Halo use photo textures? Maybe, but no single photograph is going to provide you with every lighting component of one of their shaders. Photos undoubtedly were useful in generating the various bump and diffuse maps seen in the game, but rarely could they be applied without significant manipulation.

So IMO we'll see this trend continue, and photo source will play a changing role along the way... Who knows, maybe we'll one day get to a point where game textures can largely be defined procedurally, like shaders in 3D software. But as long as artists are making bitmaps, photos can be put to good use.

bit

subagio
02-16-2002, 02:47 PM
I'll not make a large analysis of the situation here, but I voted good too. I think photo sourced textures are wonderful in the right context, but to be honest, I'd rather not work in that context. I'm a bit off from realistic games, I find them boring to work on, and frankly a little creepy to play. I mean, there has to be something just a little off about passionately desiring the thing you're shooting at to look like a real human, and react accordingly. To each his own though. I certainly still enjoy the odd FPS here or there, and I'm still in on instagib :)

I'm far, far more interested in anything but photorealism, and when you move away from that, photo sourcing only goes so far as to provide reference material.

Ultimately, Suck has a point too. I've only just moved into games from the so called 'high end' of CG. Photosourcing is an art in and of it's self, and not just a case of pointing a camera at a surface and mapping it on.

Anyway, an Ansel Adams inspired game look anyone?

--C

endseason
02-16-2002, 04:05 PM
so what do u think is the best way to have a good texture on a car model for realtime?
i mean use simpler textures and work on the env and shading?

any suggestion on how obtain a good effect trought max?

thank u.

suck
02-16-2002, 10:02 PM
Yeah, subagio maybe I did fly off the deep end on that one... it was late and the beer made me do it!

Endseason - yeah you're on the right track with the cars... one thing you may want to check out it Director 8.5 with shockwave3d... I believe their engine supports env mapping and has some really neat physics tools through Max's reactor. Check out the demos on the Havok.com site. You could conceivably make your own little car demo ;)

bit

Tad
02-17-2002, 04:55 PM
First off,
about the car texturing,
if you do it with photo based textures, you're doing it badly.
A cars texture quality is going to be defined by mainly the reflection. The texture is only good for showing the details,
such as build seams. bottom line, gran turismo 3's texturemaps
were definetely not all photo based(sure maybe they used
some photos in there somewhere, for somethings, nothings 100% of course).

Anyways, personally, I think the look of almost all pc games these days, is pretty weak, just finished playing through return to castle wolfenstein, I was really impressed with the lighting,
and the textures were pretty high-rez, but everything looked
like it came from a photo! instead of looking like it is a piece of artwork.

personally, I just cant stand that,
but considering how big of textures you can use in games
nowadays, it's alot easier to take a photo than paint by hand some gigantic texture.

Blue
02-17-2002, 11:11 PM
Originally posted by Tad
everything looked like it came from a photo! instead of looking like it is a piece of artwork.

Ok so this raises another question, are games art?

subagio
02-18-2002, 04:12 AM
No! Not this again. I have this conversation at least once a year, and it NEVER has a conclusion. This is based on the fact that Gaming is both an evolving new thing as well as a multifacted thing with so many styles and genres (even before you start talking about the artwork) that it defies a simple description. Let alone the fact that any blanket description of art in general is just as lacking.

Some would immediately argue that art isn't simply 'beautiful things to look at', many would question the gaming content of Myst, and I'm sure you'll get the odd one about 'Huh? Disney? What have they got to do with anything'. They'll all have a grain of truth to them somewhere and the whole thing will go round in circles for weeks!

Cut it short now! Save yourselves! Gaming's artness is in a quantum superposition. It's both art and not, something that isn't resolved until it's viewed by a subjective viewpoint.

--C

Tad
02-18-2002, 12:59 PM
I dont think it's that tough of a subject.
When you think that many studios are separated into 3 groups,
artists, designers, and engineers.

Saying the artwork in games isn't art, is a HUUUUUUUGGGGEEE
insult to the artists, i mean HUUUUUUGGE!!!!!
If you say something like that, I'll just wait to hear the banjo
music in the background, and look for you're wedding ring
on your cousins finger!!

When I made the comment about photo textures looking
like photos instead of pieces of art,
I meant that photo textures are really just quick, and easy pieces of art, they're STILL art, just really easy and quick(and maybe
not very good) art. There is still lots of manipulation you must do to the photo to get it to work right, and then of course there
is the model, and lighting and overall composition of what you are texture mapping.

So, I suppose games as a whole might be possible to think of
as not being art. But EVERYTHING YOU LOOK AT IN ALMOST ANY GAME IS A PIECE OF ARTWORK, period

:rolleyes:

suck
02-18-2002, 01:23 PM
Tad,

I think you're missing the point here. Nobody's saying anything that should insult anyone. Of course the art assets in a game are art... er, whatever "art" is! It seems to be a label that has no definition, really. Yes, there are visual objects in games that are made by people to represent things. It's much the same as arguing that "of course film are art because the sets are art"...

But what Chris is talking about is completely different... referring to the game as a whole, and as a genre. Without a solid definition of what art is, it is a pointless debate.

Just a thought... most art is attempting to communicate something. This can be simple or profound, literal or buried in layers of symbolism. It's trying to help the viewer look at the world from a new angle. This can be anything from "We are all clones in a dead society", to "War is bad", to "Look how hot this chick is!" :)

If anyone wants to add to this definition it would be good to hear.

CADster
02-18-2002, 11:02 PM
Excellent post Suck.

I perfer to skin by hand (or from scratch, as some call it) but i always dont have the time to do it. I do have the time on all personal projects and i think the extra time spend making every pixel is a just reward for the final look of the unit (even it it makes it look more 'photoreal').

I have skinned a ton of cars over the years and i perfer to skin cars by hand over using photos (and i have done it both ways). Photos of cars all seem to have the same problem, a light source (and its always where i dont want it to be). With a good program like Photoshop and the time i believe you can skin your unit exactly the way you want (of course the same ammount of time, or less removing the light source from the photo would arguably yeild better results).

Below is a car i did a while back. I had a ton of source material for this but none of it was any good, so i did the skin by hand.

first, the skin (orginally a bmp at 512x512, The game uses 512 textures, and this is a good thing IMO)
http://www.cadster.com/PICS/no-8-lmr.jpg

second, the rendered car.
http://www.cadster.com/PICS/lmr-render.jpg

If i could of gotten pics of this car that did not have the sky reflecting on the body, or an unwanted shadow, im sure a touched up photo would of looked better as a skin. But would it of made me feel better as a job well done ? (i bet not). This skin took me over a full day to complete (a far cry from the boxy tank textures i did in another post).

Games are art (at least the graphic side of it is IMO). If it was not art, i would not sign my work :)


*edited* to get one link to work and add last sentence.


CADster

dtek8
02-19-2002, 06:49 PM
i would just like to add to the debate about art and say that maby it not nessisary to restrict art by defining exactly what it is e.g. communication or even say "are games art",

like suck says a word that has no deffinition....

i think the word art is in its self a word created to define this very prosses and we should not restrict it,

art can be so many things a singer is a artist a craftsman is a artist ,

and so on of course games are designed as entertinment, and this experience can be aided and improved asthetically by the input of artists, sometimes however art created when someone expresses themselfs for some reason, a strange phonominon, i often create not for others but just because i have this strange itch in my head that compells me to, make the thing i imagine phisicall,,,,,,,

and my view on photo texture is that in the prosses of creating texture it is not so important what means we use(provided they r origonal etc) but that the finished product looks great, i think useing a photo as a texture is fine but we have to do more work than this to make the photo look good,, if there is time,, im a big fan of the quake textures hand painted and the finished game has the apperence of a moving comic book wow!!! though i guess this effect would not always be suitable, we must be adaptable and flexable and seek to create amazing graphics that suit the context of the subject in hand...

hope this makes sense written in a rush in a internet cafe sorry about the spelling,, hehe!!

d

Tad
02-20-2002, 12:24 AM
Cool car man!
did you work on test drive: Lemans ? or is that just for personal portfolio/practice? Anyways, I like it!

Sory , i didnt read any of the replies to my post also,
and I think I used my my angry post quota for the week anyways, hehehe

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