Sbuilder altitude bitmaps

[Guest ScottR]

I guess Luis Sa could best answer this one.I have had great success using the USGS finished seamless downloads to create mesh scenery with Sbuilder. The Sbuilder BSQ to Bitmap tool produces an altitude bitmap that is an RGB with the green value appearing to represent the altitude, but the value changes in "bands" from 0 to 255 as altitude increases up the side of a mountain. I.e. a smaller G value in an adjacent band can still be higher altitude than a larger value in an adjacent band. My question is. Can you use an image editor (e.g PSP) to adjust the bitmap to modify the altitude? If so, what are the "rules" governing the format of the bitmap and what colours represent each altitude?cheersScott

[Guest Horst]

Hello,Yes you can use a paint programm, save it to the same format.Please read in Sbuilder Options/Preferences/other settings the Help buttom (also press OK to continue).I think this explains the colourisation.RegardsHorst

[Guest ScottR]

Thanks Horst, I have had a look at the help info. I am confused by the fact that on the mesh bitmap that Sbuilder generates there is not just one RGB value for a specific altitude. If the mesh map covers a mountain for example, the G value starts off at say 10 at the base of the mountain then goes gradually up to 255 as you move up the slope, then it drops back to say 4 or 5 then starts to rise again. In other words there are bands of 1-255 G values as you move up the mountain. Sbuilder interprets the map fine and the mesh looks great in FS9, but if you want to "tweak" the map a bit by painting in a different colour, how do you know what colour to choose for each altitude since the same colour seems to represent a different altitude depending on which band you are in?Scott

[Guest Horst]

Hello Scott,Have a look to your RED value!For example 400m = R 1 / G 145 / B 010 m = R 0 G 10It is a time consuming work.Some threads down I linked this article:http://www.shadedrelief.com/dem/dem.htmlSome ideas, worth to read.Another thing to mention:The LOD level and the TMVL setting in the fs9.cfg.I uploaded once two screenshots to an Austrian forum.First link will show you the Matterhorn in Switzerland.LOD9 mesh and TMVL =19 in the fs9.cfg:http://www.wcm.at/forum/attachment.php?postid=1402927Second the same dataLOD9 mesh and TMVL=20http://www.wcm.at/forum/attachment.php?postid=1402928So take care about the relationship between these two values in the FS game.Horst

[Guest luissa]

Scott,Horst pointed you to that Help message that explains the altitude.0 meters is B=255 R=G=0 so blue is for water or 0 meters.For an altitude of X in meters you have:X= 256 * R + G with R(red) going from 0 to 255 and G(green going from 0 to 255). And B=0If you are in a given band, it is to use a paint programe to change the green channel. But if the mountain spans sveral REDs than it is more difficulty if not impossible.May be there exist a more useful format, but the one I adopted was the first that came to my mind.Luis

[Guest ScottR]

Thanks Luis and HorstI now understand the bitmap and can adjust it knowing what I am doing!!Scott