Author Topic: Parallax mapping - Height maps and mipmapping?  (Read 2838 times)

0 Members and 1 Guest are viewing this topic.

Offline DaBrain

  • Screensniper
  • 212
    • Shadows of Lylat board
Parallax mapping - Height maps and mipmapping?
Does it make sense to create a mipmaps for height maps?


It's a bit hard to for me to see what kind of good/bad results that would have.
--------------------------------------------------
SoL is looking for a sound effect artist
Please PM me in case you want to apply
---------------------------------
Shadows of Lylat - A Freespace 2 total conversion
(hosted by Game-Warden)
----------------------------------

 

Offline Zacam

  • Magnificent Bastard
  • Administrator
  • 211
  • I go Sledge-O-Matic on Spammers
    • Minecraft
    • Steam
    • Twitter
    • ModDB Feature
Re: Parallax mapping - Height maps and mipmapping?
Does it create unecessary issues or filesize in doing so?

And wouldn't height maps be used only on larger ships anyway? I suppose it becomes a question of visibility range and rendering.

You also don't have to create a full set of mip-maps.
Report MediaVP issues, now on the MediaVP Mantis! Read all about it Here!
Talk with the community on Discord
"If you can keep a level head in all this confusion, you just don't understand the situation"

¤[D+¬>

[08/01 16:53:11] <sigtau> EveningTea: I have decided that I am a 32-bit registerkin.  Pronouns are eax, ebx, ecx, edx.
[08/01 16:53:31] <EveningTea> dhauidahh
[08/01 16:53:32] <EveningTea> sak
[08/01 16:53:40] * EveningTea froths at the mouth
[08/01 16:53:40] <sigtau> i broke him, boys

 

Offline taylor

  • Super SCP/Linux Guru
  • Moderator
  • 212
    • http://www.icculus.org/~taylor
Re: Parallax mapping - Height maps and mipmapping?
Does it make sense to create a mipmaps for height maps?
It would affect speed (remember that it if can transfer a smaller mipmap level over the bus then it will be faster than without mipmaps), but it probably won't affect quality all that much.

One possible change is to modify your height map on lower mipmap levels to give you more of an effect so that you can still see it well at a distance.  Whether that would actually be worth the effort would really depend on the specific content though.


You also don't have to create a full set of mip-maps.
Although the code is hacked to allow such a thing, it really is best to always create a full mipmap chain.  About 94% of the memory required for mipmaps is in the first 2 levels, so the full chain really isn't going to hurt memory wise, but it can really help performance wise both for rendering purposes and because the game doesn't have to do anything special so that a partial chain will work.

 

Offline Zacam

  • Magnificent Bastard
  • Administrator
  • 211
  • I go Sledge-O-Matic on Spammers
    • Minecraft
    • Steam
    • Twitter
    • ModDB Feature
Re: Parallax mapping - Height maps and mipmapping?
So how many levels is considered a "full" set?
Report MediaVP issues, now on the MediaVP Mantis! Read all about it Here!
Talk with the community on Discord
"If you can keep a level head in all this confusion, you just don't understand the situation"

¤[D+¬>

[08/01 16:53:11] <sigtau> EveningTea: I have decided that I am a 32-bit registerkin.  Pronouns are eax, ebx, ecx, edx.
[08/01 16:53:31] <EveningTea> dhauidahh
[08/01 16:53:32] <EveningTea> sak
[08/01 16:53:40] * EveningTea froths at the mouth
[08/01 16:53:40] <sigtau> i broke him, boys

 

Offline DaBrain

  • Screensniper
  • 212
    • Shadows of Lylat board
Re: Parallax mapping - Height maps and mipmapping?
Does it make sense to create a mipmaps for height maps?
It would affect speed (remember that it if can transfer a smaller mipmap level over the bus then it will be faster than without mipmaps), but it probably won't affect quality all that much.

One possible change is to modify your height map on lower mipmap levels to give you more of an effect so that you can still see it well at a distance.  Whether that would actually be worth the effort would really depend on the specific content though.


Thanks, that clears things up.
Modifying the mipmaps is no problem.
« Last Edit: March 23, 2008, 06:47:42 am by DaBrain »
--------------------------------------------------
SoL is looking for a sound effect artist
Please PM me in case you want to apply
---------------------------------
Shadows of Lylat - A Freespace 2 total conversion
(hosted by Game-Warden)
----------------------------------

 

Offline taylor

  • Super SCP/Linux Guru
  • Moderator
  • 212
    • http://www.icculus.org/~taylor
Re: Parallax mapping - Height maps and mipmapping?
So how many levels is considered a "full" set?
As many levels as it takes to get all the way down to 1x1.

 

Offline Nuke

  • Ka-Boom!
  • 212
  • Mutants Worship Me
Re: Parallax mapping - Height maps and mipmapping?
il be glad when we have a materials system. it might make since to have different normal maps for different lods whilre retaining a single set of diffuse/glow/shine/env maps for the whole. this way you can make lower lods look better.
I can no longer sit back and allow communist infiltration, communist indoctrination, communist subversion, and the international communist conspiracy to sap and impurify all of our precious bodily fluids.

Nuke's Scripting SVN

 

Offline DaBrain

  • Screensniper
  • 212
    • Shadows of Lylat board
Re: Parallax mapping - Height maps and mipmapping?
In some rare special cases, it might make sense, but for the most part using more maps isn't a good idea.
There is the memory need and the additional lods plopping if you do not only change the geometry but also the maps.

If the player's PC can take a plus of memory usage, it could probably also take slightly higher lod distances, which might help just as well.
(Again, "in most cases"... I know there are some models than be "lodded" extremely well, but would need a normal map to keep the structures. This might apply to some asteroids, I guess.)
--------------------------------------------------
SoL is looking for a sound effect artist
Please PM me in case you want to apply
---------------------------------
Shadows of Lylat - A Freespace 2 total conversion
(hosted by Game-Warden)
----------------------------------

 

Offline lufusol

  • 20
Re: Parallax mapping - Height maps and mipmapping?
So how many levels is considered a "full" set?
As many levels as it takes to get all the way down to 1x1.
Mipmaps DO go all the way down to 1x1, but I don't understand why.  Maybe it's just so the GPU can use that pixel if it only needs to fill a single pixel instead of calculating which of the 4 pixels in a texel is best (or which to blend)?  I was under the impression that the smallest texture unit the GPU processes is the texel (a group of 2x2 pixels) and I thought that's why textures always need to be a power of 2 (2x2x 8x8, 4x16, 512x2048, etc)

Anyway, example given, let's say your texture is 512x512 : a full set of mips will look like this:  256x256, 128x128, 64x64, 32x32, 16x16, 8x8, 4x4, 2x2, 1x1 (i guess) so at 512x512, you get a maximum of 9 mipmap levels.  In that case, a full set is 9 mips. 

Now would someone please clarify the texel thing for me, or did I already guess it?

 

Offline Strygon

  • 28
  • Ui-beaaaaaaaaam~
    • Steam
Re: Parallax mapping - Height maps and mipmapping?
Holy necropost batman.
Makes missions sometimes.
Finished Projects: Operation: Cloak and Dagger

Current Projects: Scrolls Part 2 (FREDding), Dimensional Eclipse (Art),
The First Contact War, GTDr Amazon HTL

[23:22] strypolygon: andrew
[23:22] strypolygon: i have one favor to ask of you
[23:22] strypolygon: never try speaking german again
[23:23] Andrewofdoom: No.

[18:50] 島風改八百三: the duck has multipli
[18:50] 島風改八百三: many duck
[18:50] 島風改八百三: left side
[18:50] 島風改八百三: even side
[18:50] 島風改八百三: handle it

[21:34] MP-Ryan: Why on earth would you Google this
[21:34] The_E: why would you not

[06:46] Strigon: how big is a mini-campaign again?
[06:46] Asteroth: smaller than a campaign
[06:47 ]Strigon: thanks

[05:56] Strigon: If I had to take a shot for each time I randomly decided to change the UI sounds, I'd have died of alcohol poisoning by now

[17:36] qazwsxal: time to have some fun
[17:41] z64555: VC++5 is not my idea of fun

[EatThePath] do your missiles do anything absurd?
[Strigon] describe absurd
[Strigon] the entire mod is absurd