32k Spec Map Case

[selden]

Walton,

What's specular color and power did you use?
Was it exaggerated for effect, perhaps?

Or maybe the land specularity mask is brighter than necessary. Certainly there should be some brightening in deserts and snow, but I think I agree with Fridger that the pictures you took seem just a little too bright.

Alternatively, maybe the specularity code isn't as general as it needs to be?

[wcomer]

Selden,
Here is what is in my .ctx file.

Code: Select all

   Color [ 0.85 0.85 1.0 ]
   Texture "BlueMarbleJPG85.ctx"
   SpecularPower 25.0
   SpecularTexture "BlueMarbleSpec.ctx"
   SpecularColor [ 0.5 0.5 0.55 ]
   HazeColor [ 1 1 1 ]
   HazeDensity 0.3

This all seems standard from the default solar system file. However, Celestia pre9 has been having a great deal of difficulty handling the large spec map files and is behaving very erratically. I will have to build a full VT in order to get celestia's behavior to normallize (or maybe try pre10.)

Fridger,
I expect nothing less than your honest and brutal opinion; that is what I'm asking for. I put the pictures up precisely because I thought that they looked like an overkill but I wanted the opinion of those more knowledgeable than me.


cheers,
Walton

[wcomer]

It turns out that celestia was just choking on the giant 8kx8k spec tiles. When I reduced those and set up level[0-1] 512x512 specmap tiles... the ugliness is greatly diminished. I'm not sure what the problem was. Here are three revised images.

Base image:


With specular power but not spec map:


With specular map:


I'm still looking for opinions as too whether it is too much or not enough. Perhaps the best way to do this is to let people test out the level[0-1] 512x512 tiles and get back to me. If this seems right then I will work with Mario to host a full VT specmap.

cheers,
Walton

[JackHiggins]

But the coral reefs & green seas off australia aren't being specularised...?!

[wcomer]

I don't think there are any good solutions for automating the extraction of specular reflections for the reefs. Unfortunately they have a very wide range of colors that show up in a lot of the land vegetation. I suspect that sooner or later (probably much later) someone will go through the bluemarble images and create a specular map by hand. I don't envy that person. Until then the best we can do is use a 32k specular map based on automated procedures.

[jim]

Hi Walton,

I think I should tell you some of my tricks of building a specular map. First a shot with my automaticaly generated 8k spec map that demonstrade that it's possible to include the green seas without including parts of the green land.

You should know there is a very good indicator to differ between green water and green land The red component of all water is very low (expect the Amazonas).

Ok my steps for building a spec map:
Fist I split my work into coast lines and small lakes. The 8k spec map from BlueMarble is very usefull as separator for this job. Build a selection of this and then expand this selection so that the large lakes and seas with cost is include mask. Use this mask to remove any misk from the land while you build the spec map for the coast line (green water). Later use an invertet mask while creating the spec map for small lakes. This prevents then the coast spec map.

Now the steps to select the water:
Select by color 10%-20% is OK. Build by this way with several colors several maps (5 or more). Make sure that only water is selected (play with tolorance). Use manual "tonwert" correction (don't know this in enlish) or contrast to revice this grayscale maps.
Then merge this maps. Add every map by useing this as mask for a white solid color to the current map.

Finally when the raw spec map is ready use gaussian blur 0,3. Then copy this map and use it as mask with a white solid color in the same dokument. After that use gaussian blur 1,0 for the backround. This makes the spec map softer without looseing details.

Ok, it's much work and will take several hours but the result is a good specular map.

I hope this helps a bit.

Bye Jens

[Guest]

Hello gyus,

you should not spend efforts to create your own spec map. In the original BlueMarble 43K texture, a beautiful spec map is included as a separate TIFF channel. Haven't you found it yet?

[bh]

Blimey!!

[jim]

Hi Walton,

Have you checked the included speculare map in the BlueMarble 43K texture?

Bye Jens

[wcomer]

I just tried to pull it out using Netpbm.

Here's what I did:

Code: Select all

tifftopnm -alphaout=- -byrow land_west.tif>alpha_w48k.pgm
pnmscale -xysize 16384 16384 alpha_w48k.pgm>alpha_w32k.pgm
pamdice alpha_w32k -outstem t -width 8192 -height 8192

All four of the resulting 8192x8192 grayscale tiles are color #000000 at every pixel. So either (a) I'm doing something wrong, (b) -alphaout doesn't work as documented, or (c) there is no included specular map.

I hate to second guess the guest so I presume that I'm not using the Netpbm tools correctly. Let me know what your experience has been.

Walton

[jim]

Hi Walton,

Sorry I know absolute nothing about Netpbm. You should ask Selden for help. I can only say that the 8K BlueMarble tiff has included an speculare map.

Bye Jens

[selden]

I've never tried to extract an alpha channel from a tiff image, but I certainly could believe there are bugs in the code. The docs say tifftopnm uses its own routines to decode tiff images rather than using the standard tiff library.

You might try something a little different just to see what happens: send the alpha channel to a named file instead of standard output, and not dicing it.

e.g.

Code: Select all

tifftopnm -alphaout=alpha.pgm file.tiff > /dev/null

[Buzz]

I did not find any spec map in the 2 x 21k version either using PhotoShop. I don't think there is any, just a rudimentary one in the 8k.

[Guest]

Forgive me, I'm new (and don't even have an logon for the forums yet), so my thoughts may be way off base.

Assuming you can't extract a spec map from the TIFF files, why not create the spec map from the 32k surface texture - it is already conveniently broken up into tiles. If enough people get on board to help and do a set of tiles each it would almost be manageable wouldn't it? 2048 tiles by 20 people would be 100 tiles each. Still a lot of work, but not impossible.

A gimp script or two to automate the worst of it so it's only a matter of tidying trickier land edges and lakes would certainly help.

Is this feasible, or am I being foolish?

Leland McInnes.

[jim]

Hi texture makers,

I've built a basic 43k specular map for the Bluemarble texture. Basic means that only the oceans are maped but all the small waters (river and lakes) must be still added. With the 43k Bluemarble TIFF's and some image edit it should be possible to do this. Sorry, I see at the moment no chance to get (download) the Bluemarble TIFF's to do this job.
Now there are some fine people in this forum so I hope a 32k spec map (VT) with all waters will be soon available.

http://www.celestiaproject.net/~jim/files/basi ... ec_43k.zip (1,13mb, splited in 21k west and east tile)

Bye Jens

[t00fri]

Hi texture makers,

I've built a basic 43k specular map for the Bluemarble texture. Basic means that only the oceans are maped but all the small waters (river and lakes) must be still added. With the 43k Bluemarble TIFF's and some image edit it should be possible to do this. Sorry, I see at the moment no chance to get (download) the Bluemarble TIFF's to do this job.
Now there are some fine people in this forum so I hope a 32k spec map (VT) with all waters will be soon available.

http://www.celestiaproject.net/~jim/files/basi ... ec_43k.zip (1,13mb, splited in 21k west and east tile)

Bye Jens

Thanks Jens!

While the spec reflections in the innumerous little lakes is the main reason for going to such hires spec textures, this is a good start...

Bye Fridger

[Don. Edwards]

Well if anyone has $11,995 laying around doing nothing we could get a specmap to die for from the TrueEarth site. Although their main textures color is just the worst I have ever seen they have a beautiful specmap with everything we all want. Actually they have two nice ones with ice and without. If they can do this and ask what they asking someone should be able to pull off the same thing for pennies on the dollar or for free.
TrueEarth has a free downloadable sample of their textures at 1350x675.
Here is a link to there site if anyone is interested http://www.truearth.com/index.html

Here are what their specmaps look like. Click the thumbs for the full size.
-

As you can see or barely see most of the rivers are even covered well. I suppose we can make our own and use these as a measuring stick.

[Buzz]

Good news: no need for megabucks to get a decent specmap! I have posted a 16k specmap for earth at my site (http://home.tiscali.nl/celestia/), and I have the "raw material" for a 32k one!!! So, another addon to celebrate the 1.3.1 release! I had to split it into three files because of restrictions of my provider

Unfortunately, I did not succeed in creating the 32k version yet. The 16k one was made with Fridger's Virtualtex, that did a great job until I tried 32k with an eastern and a western part... Any ideas Fridger? I have a pentium III 1GHz, 384 MB RAM, SuSE 8.1. Are there any minimum size requirements for partitions, swap space or RAM when you process 32k textures?

[danielj]

Sorry,but in your site there is only a 8k specmap.I am looking for a DDS or JPG specmap file,because even a 8k specmap png is too much to my system.I read in some place that Normal Maps "incorporate" the specular.So if I have a Normal Map,I don?t need a spec map?

[Don. Edwards]

danielj,
No specmaps can't be in the normalmap as far as I know. We used to plug the specmap into the main texture by placing it in the alpha channel. But it tended to make the texture larger and prohibitive for faster downloads. That is why Chris implemented the separate specmap scheme. There are still some textures floating around that I and others have made that have a specmap plugged in. I only do it know for special projects so that there are not a who bunch of extra files to include. Hope that clears up you misunderstanding about this.


Don. Edwards