Celestia Forums

this is my mars code:


i also try adding
BumpMap "marsbump1k.jpg"
BumpHeight 2.5

or puting BumpHeight 0.0

but what i see is this:


and this


and changing tha my view angle i see this


did you notice that what has to be high is low(like the mountains) and whats has to be low is high?
what can i do?

Yeah I get that to.

It really does my head in to see reversed topography like that. I used to do that and get paid for it!

Regards...bh.

that is a natural optical illusion. Change your angle, and it will change.

but before putting the new 8k dds textures, it didnt happend. and the same thing happens on the moon Mimas, with the big crater, once i see it like a crater and once like a very big mountain.

ElPelado,
Please listen. Its an optical illusion and its in many textures. Mars shows this because most if not all Mar textures have shadows along the right side of craters and the left side of the mountains. To make the illusion go away you need to turn Mars so that the sun is at the right of the planet. Nothing can be done to fix this until someone uses a image editer and go in and repaints all the shadows out. Then you would have a nice uniform texture. Even the Earth textures have this problem to a small degree. It just goes with the territory. You will just have live with it. We all do.

It's certainly nothing to do with your normal map, since you don't even have that installed at present! Celestia is case-sensitive; you should have written:


Grant

can some one please explain me why if my mars code is this:


i can still see the different altitiuds on mars?
the only possible that i think about it is that on the texture map that i use there is also included a bump or a normal.


and an other thing can some one please write me the code for puting a normalmap.

its only NormalMap "texture.dds"
or should i put also BumpHeight?
thanks

ElPelado,

Look more closely.

The shadows do not change as the planet rotates.
They are correct at sunrise but, since they do not change, are reversed at sunset.

This is because the shadows are part of the dds picture that you are using as the surface texture. They are not caused by a bumpmap.

Fridger has made many postings about how to create normal maps. Please read them.

If I understand correctly, the problem is not so much the normal map, which can be created in a straight-forward way from topographic data, but rather the albedo (color) map, which ideally should not include any shading due to topography. Unfortunately, most surface maps incorporate topography via "shaded relief", which needs to be eliminated to make a useful albedo map.

In principle, if you have an accurate normal map, and you know the direction of the illumination used for the shaded relief, it should be possible to remove the relief shading from the surface map, producing a useful albedo map. I don't know if anyone has tried this, but it would be an interesting experiment.

- Hank

Didn't anyone notice in the sample of his .ssc file that all the bumpmap entries are # out. No wonder he isn't seeing any bumpmaping.

ElPelado,
Change this:
Texture "Redmars8k.dds"
#BumpMap "marsbump1k.jpg"
#NormalMap "Redmars-normal-8k.dds"
#BumpHeight 0.0
#BumpHeight 2.5

To this:
Texture "Redmars8k.dds"
#BumpMap "marsbump1k.jpg"
NormalMap "Redmars-normal-8k.dds"
#BumpHeight 0.0
#BumpHeight 2.5
Or:
Texture "Redmars8k.dds"
BumpMap "marsbump1k.jpg"
#NormalMap "Redmars-normal-8k.dds"
#BumpHeight 0.0
BumpHeight 2.5

Give this a try and see if you start getting bumpmaping to work.

HankR wrote:If I understand correctly, the problem is not so much the normal map, which can be created in a straight-forward way from topographic data, but rather the albedo (color) map, which ideally should not include any shading due to topography. Unfortunately, most surface maps incorporate topography via "shaded relief", which needs to be eliminated to make a useful albedo map.

In principle, if you have an accurate normal map, and you know the direction of the illumination used for the shaded relief, it should be possible to remove the relief shading from the surface map, producing a useful albedo map. I don't know if anyone has tried this, but it would be an interesting experiment.

- Hank

Yes I did plenty of experiments along these lines. The idea is pretty obvious;-). So far my results were never too satisfactory, despite going into the right direction.

There are simply too many parameters to fiddle.

a) azimut of sunlight. That is often quoted (SpaceGraphics RedMars, for instance: 60 degs).
b) Altitude?
c) Rescaling of compensating bumpmap

Bye Fridger

Don. Edwards wrote:Didn't anyone notice in the sample of his .ssc file that all the bumpmap entries are # out. No wonder he isn't seeing any bumpmaping.

But El Pelado's problem was that he thought he could see bumps despite having bumpmapping and normal mapping turned off - it's just (as you said first time out, Don) a trick of the relief shading in the original texture.

As to the BumpHeight question, El Pelado, why don't you just experiment and see what happens? It's how most of us learned all we know about Celestia ...

Grant

thanks for all the help!
the problem is that i tought that because of the shadow on the texture, there was an bumpmap or something like that.
now i understand that the shadows are drown in the texture. i want to edit it with the photo shop(i have the dss plug-in), but when i open the texture, the program crashes.

about the normalmap, i think that the problem with it is that i can not see it. maybe becasue my video card. but its strange, cause i can see others 8k dds textures, but this normal map i can't.

i will keep trying to do something else.

ElPelado wrote:thanks for all the help!
the problem is that i tought that because of the shadow on the texture, there was an bumpmap or something like that.
now i understand that the shadows are drown in the texture. i want to edit it with the photo shop(i have the dss plug-in), but when i open the texture, the program crashes.

about the normalmap, i think that the problem with it is that i can not see it. maybe becasue my video card. but its strange, cause i can see others 8k dds textures, but this normal map i can't.

i will keep trying to do something else.

You mean the DDS (not dss) plugin, I guess. It crashes, since you have probably not calculated beforehand, how much memory you /need/ and how much you /have/ available. I bet you started right away with 8K textures;-), instead of first practising with a much smaller one...

Photoshop and the latest NVIDIA plugins (5.4.5) work well also with relatively little RAM (~256MB), if you assign manually sufficiently much virtual memory on your harddisk! I am sure you have studied your Windows manual and know how to increase virtual memory...

Bye Fridger

ElPelado wrote:about the normalmap, i think that the problem with it is that i can not see it.

Difficult, when you have a shaded relief map on top of it. Take off the overlying Mars texture, and replace it with a plain white texture. With this "White Mars" you'll be able to see the effects of bumpmaps and normal maps clearly.

Grant

what i wanted to say is that maybe my computer doesnt support that normal map, and i cant see it.

what i wanted to say is that maybe my computer doesnt support that 8k normalmap and because of this i cant see it

ElPelado wrote:what i wanted to say is that maybe my computer doesnt support that 8k normalmap and because of this i cant see it

And what I'm saying is that you really need to look at the normal map used under a very plain texture before you decide that.

Grant

i did what you told me to do. and here is my result:


i used no texture, only the normalmap. in some places i can see the mountains, but i see those strange colors. i also try in other Ctrl+V mode and i saw a withe texture with some mountains.

Unfortunately, I'm unable to load the 8k Mars bump map on my system, but perhaps someone who can load it could tell me how well it works. Does it provide an adequate high-resolution representation of the topography when used without a suface texture map? I'm wondering whether, if it were possible to remove the topography from the surface texture, would the bump map provide sufficient topographic detail? Can anyone comment on this?

- Hank