Normal mapping discussion - how much can HL2 handle ? consequences for us modders..

[Goetterfunke]

As HL2 supports normal mapping, we should know how extensive it can be used. ( If you dont know what normal mapping is, use the search function in these boards )

I wonder if the charackters only will be normal mapped, or other things like weapons, buildings etc as well

As normal maps cant be compressed very well theres a limit of use for it to keep the memory waste acceptable.

So for us modders it would be important to know how much normal mapping can be used, as we have to model our charackters / weapons with way higher polycounts if we want to take advantage of that feature.


Any thoughts / info yet ?

 

[dawdler]

I dont think anyone can even make a guess before we've seen the actual engine in hard work. We have absolutely no idea how fast it is. And even after that, it will probably be VERY dependant on the graphics card... And the level.
Lets say you a really cool level, with heavy use of shaders and normal mapping. If the 9700/9800 can achieve about 40-70 fps (which is playable), how would the 5900 handle? Half speeds are 20-35... That's unplayable in an fps with alot of movement. If the 9800 does 20-35, you KNOW its unplayable on the 5900
But the engine will scale! So will models really have normal mapping? Will you just see lower detail? Nobody knows exactly how the scaling work either.

But in *theory* you should be able to add as much detail as possible, if its playable the worst card there is on highest detail, the rest will just scale down to acheive the same speed. And if it isnt playable on it... It will scale it down anyway

 

[EVIL]

you can normal map everything you want, but I suggest not to do it if you want to have it still playable for lower memory graphiccards (128mb and lower)

 

[Goetterfunke]

ok, this answers pretty much questions

http://www.halflife-files.com/E/index.php?extend.166

So then dont use normal maps on everything themselves, they sometimes use bump and specular maps or none of them all

bump maps can also be converted to normal maps so we wont need to do high poly versions of all our models

 

[HiroProtaganist]

from the chat

<valve|gary> "Can I put normal maps on everything?"
<valve|gary> In dx8, you can put specular normal maps on all models, and you can put diffuse and specular normal maps on world geometry (including displacement maps).
<valve|gary> In dx9, you can additionally put diffuse normal maps on models.
<valve|yahn> You also have full control over the rendering loop and could even insert your own rendering primitives ( as long as you ultimately end up rendering triangles... )
<valve|david> The output can potentially pass data to the receiving input, for example a wheel can pass its Position as a value from 0 - 1 to the Alpha input of a sprite, so as you turn the wheel the sprite gets brighter.

 

[Goetterfunke]

yes, but if you put normal maps on anything, the memory will get an overkill

so for charackters it makes sense, for weapons im not sure
if you have a 1024 skin for a charackter, then its another 1024 for normal map and that cant be compressed very well so its more than twice the memory useage

 

[HiroProtaganist]

personally it's all latin to me. I'm just a modeler. But it seems to me that if you can accomplish what you are looking for without using huge "normal maps" (btw - if someone wants to explain this to me i'd really appreceiate it. I have a feeling i know what it is but by a different name) the why bother?

 

[Vulcan3d]

HiroProtagonist (Great name... I LOVE Snow Crash!)... I'm pretty certain that normal maps in game-engine-speak is similar to bump maps for us animation people. I guess because normal maps move things in relation to normal to the triangle.

24 bit file... RBG channels encode movement in XYZ, the same way 8bit bump maps encode movement in a Z axis.

I think it also gives you much better depth sensitivity to dynamic lighting in games... I'm pretty sure Tenebrae uses Normal maps...

Seriously, took me a while to figure that out... I have very little idea where I would use it, I'm so used to the usual techniques...

 

[zapher]

Just do really UNDERDETAILED and then add some more details if possible when you receive the game
That way you don't have to do all the work all over..