ray tracing and bump mapping

Peet · Post by **Peet** » 13 Oct 2006, 20:35

feanix wrote: So, for instance, a crater would look more 3d, rather than a simple black splodge.

Have you not noticed the ground deformation?

rattle · Post by **rattle** » 13 Oct 2006, 23:15

You don't notice them unless you play in heightmap mode on some maps.

SwiftSpear · Post by **SwiftSpear** » 13 Oct 2006, 23:21

feanix wrote:i wonder if bump mapping for the terrain might be an option? I come from a Source Engine background with regards to modding and stuff, and afaik bump mapping doesnt drain too much.

The only hitch is how to include a bump map in the map making process. It might be an idea to tie a bumpmap tile to terrain types in the text file (its been a while since i tried making a map for spring, i can't remember what that file is called).

This would be more difficult, i think, but it would also be great to have bump mapped decals. So, for instance, a crater would look more 3d, rather than a simple black splodge.

As already stated, it's already there in the new map format, and it looks really cool.

Post by **jcnossen** » 13 Oct 2006, 23:33

You don't notice them unless you play in heightmap mode on some maps.

There is no non-heightmap mode..

SwiftSpear · Post by **SwiftSpear** » 13 Oct 2006, 23:35

jcnossen wrote:
You don't notice them unless you play in heightmap mode on some maps.
There is no non-heightmap mode..

He means where you get colored bands that represent altitude.

feanix · Post by **feanix** » 14 Oct 2006, 14:56

How many craters have you seen that are perfect bowls? Bump mapped craters would give you more detail to play with than you can get with a terrain mesh deformation.

mehere101 · Post by **mehere101** » 17 Oct 2006, 00:58

NO! Units need bumpmapping before craters.

feanix · Post by **feanix** » 17 Oct 2006, 10:07

mehere101 wrote:NO! Units need bumpmapping before craters.

There are faaar to many units and they are faaar to small for that to be really practical. You might only notice it if you zoomed in on a unit and watched it for a few seconds. Zoomed out, you'd never notice. However, you would likely notice crater bumpmaps every time without having to zoom in (unless you were really zoomed out quite far)

SwiftSpear · Post by **SwiftSpear** » 17 Oct 2006, 20:35

feanix wrote:
mehere101 wrote:NO! Units need bumpmapping before craters.
There are faaar to many units and they are faaar to small for that to be really practical. You might only notice it if you zoomed in on a unit and watched it for a few seconds. Zoomed out, you'd never notice. However, you would likely notice crater bumpmaps every time without having to zoom in (unless you were really zoomed out quite far)

It would probably habitual not to use it much on small units. It's really for the larger units which currently look rather bland.

Wolf-In-Exile · Post by **Wolf-In-Exile** » 17 Oct 2006, 20:58

FYI, Supreme Commander uses normal mapping for its units.

Bumpmapping is nice and all, perhaps to make it easier to get the hang of normal mapping, but its really obsolete in this day and age.

That being said, if the Spring devs decide a bumpmap system would be easier to implement, I won't complain either.

FireCrack · Post by **FireCrack** » 17 Oct 2006, 21:48

^There is absolutely no reason to use normal mapping over bump mapping in this case, or in most cases for that matter. When you use bump-mapping the bumpmap is expanded to a normal map at runtime, it is often quite wastefull to store a normal map on disk.

Post by **jcnossen** » 17 Oct 2006, 23:58

What are you talking about? Basically every game uses normal mapping for bumpmapping

feanix · Post by **feanix** » 18 Oct 2006, 00:29

normal mapping is a kind of bump mapping. afaik.

Post by **jcnossen** » 18 Oct 2006, 01:25

Exactly

mehere101 · Post by **mehere101** » 18 Oct 2006, 02:54

I agree that bumpmapping is only feasable for larger units, but IIRC the only way a true normal map could be done is by putting it in a new texture channel. IIRC we only have the blue channel free on the second texture, meaning that a greyscale image could be stored in it.

(I do understand this fully, I just don't want another texture layer)

SwiftSpear · Post by **SwiftSpear** » 18 Oct 2006, 06:11

FireCrack wrote:^There is absolutely no reason to use normal mapping over bump mapping in this case, or in most cases for that matter. When you use bump-mapping the bumpmap is expanded to a normal map at runtime, it is often quite wastefull to store a normal map on disk.

A bumpmap isn't expanded to a normal map. Depending on bump map technology used the bump map either does some fudgy crap or is processed into a normal map. The size difference between a bump map and a normal map is generally negligible.

The reason we use normal maps is:
a) there are standard translation library's written for them so we don't need to make any proprietary code.
b) they save the CPU time from parsing the normal information from the bump map
c) they are industry standard and most high end artists are more familiar working with normals than bump maps
d) they give the artist more control over certain aspects of the image render, bump maps have many flaws in the way they work.

Spring RTS Engine

ray tracing and bump mapping