Celestia Forums

Please people DO NOT use shaded images AS a Heightmap
this is an example of what NOT to use

this is just the first add on i opened today and the first image i looked at
just random

this is NOT a height map


Nor is this a height map



please DO NOT use these AS HEIGHT MAPS!!!

this is more like what a Heightmap for the TOP image might look like
that image looks to be a crop of a CTX or HIRES mars image
a SFS ( shape from shade ) might look like this

just a "down and dirty " quick image -- it needs a lot of work yet
and would require WAY more explaining than this thread is fore

I am getting very tired OF REPEATING things
the photoshop and Gimp tool called " Bumpmap"
Dose not and NEVER EVER did "make" heightmaps !!!
IT NEVER DID SO DO not use that tool !!!!!!
that tool ADDS shadows to a image USING a Heightmap TO ADD THEM
it dose NOT make the HEIGHT MAP

for example the texture

was ran through one of these tools to make this


i WILL fail EVERY ONE I SEE
no if's and's or buts !!!!
this is "closer" to what a Topographic /DEM / Height map "might " look like

and this STILL would need a lot of work , do to the errors put in this by using the whole image

people please , since the 1970's the question of "computer vision " has been the BANE and worst nightmare
now there are some things that "well it sort of works, some what well "
things that for a FAST PASSED first person shooter " work some what well" ( being a FPS you do not have time to pay attention to the textures and shading )
then there are things that DO NOT work well for 3d programs that ARE.... S.. L.. O.. W..
so slow that one has time to really examine the shading


3d artists have for YEARS been trying to find something "simple" , with out luck
what might work somewhat well in a FPS will not work all that well in Celestia

if you must 100% use a image that has shadows in it ( first don't)
but if you will die if you do not then
1)
REMOVE the shadows
this will require a lot of time "hand painting " the image to LIGHTEN up the shadows and to DARKEN the highlights .
this is no easy task and gets much harder the bigger the image is
2)
then use something like a combination "hi-pass" and "DOG" to come up with something that "might" look good for a STARTING POINT
you basically want outlines and ridges

3)
then hand paint the depth
-- there will be painting
( some line in a movie is stuck in my head )
" and yes there will be blood "
so yes THERE WILL BE PAINTING involved

I was NOT planning on naming names , but...

the images look nice , it is just that they are NOT height maps

bdfd
from the normal you posted above this is a 3d rendering
the light is from above and to the left

and extracting the Z access from the normal i get this reconstructed Heightmap

and that looks a heck of a lot like a black and white ( desaturated copy) of the color map

and as you can SEE the GROUND is BELOW sea-level
not good
and the ice is on top of a "Mt. Everest " of TALL plateaus

in Height maps
the lighter the tone the HIGHER UP it is
the peak of Mt. Everest would be a white #ffffff color
and the lowest place would be black #000000

I admit it is a learning process and, it doesn't bother me whatsoever. I am proud of my first attempt.

it's not bad ,just a HUGE undertaking with a VERY large learning curve
the textures for the most part look nice
and so do the ships

it is just NEAR imposable to get a good looking and passable Heightmap from a shaded or not so shaded images that both you and bdfd are using

This is the reason that i only posted two
jupiters io and callisto - they were experiments
and took WEEKS of work for each
and the Io normal i have on the ML , is frankly garbage
the mimas bumpmap STILL dose not look good after YEARS of tinkering


mind you IT IS easier to make a synthetic artificial pseudo HeightMap of a water world ,
than of a dry cratered world .

but Bumpmaps/Heightmaps/NormalMaps are not a 100% must use

try this
temporally replace the texture with a light gray only image
that way the ONLY information celestia will render IS the Height map being used

Avandar-normal.png
-- this one got left in a testing folder

and the above normalmap "Coridan_little-normal.png "


that gives you a preview

Did you use gimp for light gray ?
If yes, How (desaturate or grayscale or another) ?
How must the ssc file be ?

??????????????/
just make a new image that has a value 50%

By default the Wilbur's lighting shader is so:



Thus the post-processing heightfield's shader will match that settings. if you get colors from the shaders' elevation, they will hold that lighting position. Once the custom lights direction is specified, it must be recalculate and all maps will agree. Note that the menu's option concernig the "recompute lighting" is shown only when a shader is applied and not when one works in bumpmap/normalmap mode.



EDIT LATER:
Read "menu shader setup is shown" instead of "recompute lighting"

bdfd wrote:Hi, fenerit,
Tell us more between the 2 pictures please !
I feel the next end on this subject...

First, you must follows all that John is saying, because him and not me is the boss in these matters. I can only suggest few programs which can help, and one is Wilbur. My experiments with it are somewhat naives, since I'm not involved in these matters now.

This a random heightfield terrain on which shader has been applied a lighting from top.


This is its normalmap equivalent (scale=1)


This is how such normalmap only looks once applied on Callisto.

This is how Callisto looks with both maps.


This the Callisto' south pole. At least no seams.


I unable to tell where the things are wrongs.

P.S.
Maps are 2K

Continuing the story...
In the previous images, as shading map has been used a map which itself had lights. But if one does use its height code, the map will match with its normalmap like must be, without "false" scale height.





Note that you must not save the images as "PNG surface"; but as "PNG textures" or you will get the gray heightfield only.

irst, you must follows all that John is saying, because him and not me is the boss in these matters.

i do not care what people use
wilber is fine
i am just surprised that is still works
i was under the impression that it was OLD very OLD
"Windows 2000 and Windows XP. Earlier versions worked under Windows 9x "
guess i was wrong there is a 2012 update 1.78
http://www.ridgenet.net/~jslayton/wilbur.html
and see the tutorials on using it

i do not care what people use( never have) , as long as the map is close to technically right
and the photoshop/gimp tool" bumpmap IS NOT anywhere near to being " close to technically right "

pla879
did you read the PM i sent you
do NOT use 16 bit "bumpmaps" in the add on ( that is why the one i just checked is 1.1 GIG VS the 340 meg of the one before that. )
celestia CAN NOT use them
celestia USES 8 bit "bumpmaps"

john Van Vliet wrote:

irst, you must follows all that John is saying, because him and not me is the boss in these matters.

i do not care what people use
wilber is fine
i am just surprised that is still works
i was under the impression that it was OLD very OLD
"Windows 2000 and Windows XP. Earlier versions worked under Windows 9x "
guess i was wrong there is a 2012 update 1.78
http://www.ridgenet.net/~jslayton/wilbur.html
and see the tutorials on using it

i do not care what people use( never have) , as long as the map is close to technically right
and the photoshop/gimp tool" bumpmap IS NOT anywhere near to being " close to technically right "

I had trying to "recapitulating" with my bad english words and explication sequences all what you were saying about heightfield and normalmap-from-shading issues. Maybe now is clear why a crater's shadows cannot bring to a normalmap. And yes, Wilbur was old, until such update which I found while I was doing order in my web bookmarks. It use VC++ 2010 redistributable package.

As last remark, if the bumps of the normalmap looks exaggerated for your tastes and unfitted for your planetary/moon map, do lower its vertical scale (it was 1 in the previous images).

it takes a few days
first it has to get moved form the Admins "inbox " to the Admins "outbox"
then into MY "inbox"
that might be a few days ( about 1 to 3 days on average )

then I have to check it

depending on how many i have to look at and what i find
it might take 5 min. to 3 or 4 hours to check JUST ONE

I then post my results to the Admin


Then the Motherload Admins contacts YOU

Yes having Me in the loop DOSE add more time on to things

BUT we were getting all kinds of ( there is NO way to put it mildly) garbage posted
things that were Windows ONLY and did not work on Apple or Linux.
And things that did NOT even run on windows , add ons that well DID NOT even work , and/or were MISSING things and DID NOT WORK

no we did not


the Official Motherload Admin
had NOT YET contacted you when you uploaded a different version

you should have received a email about the errors