Looking for a VT Tile location calculator

[Shadow-Dragon-777]

A while back, like really really long ago when I was like still a kid, a tool was made that allowed you to look up where a VT tile was which would aid you in creating VT closeups. Right now I am trying to make a VT closeup for the Huygens probe but its near impossible without understanding complicated maths or a tool like the one that user Jim made.
viewtopic.php?f=5&t=3350
Sadly, this tool was hosted on Shatters net and thus doesn't exist anymore unless someone has managed to keep a copy this whole time.
If anyone could find a similar tool, that would be great as it would help me a lot for not only Huygens but also when I get around to doing Venus, Moon, and Mars landing site VT closeups.

[john71]

As I know it was made by Jens Meyer (Jim).

The name of the file was: VT-tile-calculator.zip

It disappeared in 2005, but Fridger had a copy of it.

Jens Meyer provided some textures too: Amalthea is a shaded relief map by Phil Stooke, colored by Wm. Robert Johnston
(http://www.johnstonsarchive.net/spaceart/cylmaps.html), and further modified
by Jens Meyer, Grant Hutchison, and Askaniy.

https://celestia.space/forum/viewtopic.php?f=2&t=8178

https://celestia.space/forum/viewtopic.php?f=15&t=13675

Maybe someone can contact him.

[Shadow-Dragon-777]

Jens has not been seen for a long time. Email probably doesn't work.
As for Fridger, how do I contact him? He has been gone for a few years and new people have taken over development of Celestia since.

[john71]

Maybe he is the same person, I don't know. Seems like a busy man.

https://www.desy.de/~t00fri/

Try this:

https://tools.geofabrik.de/calc/

[Sirius_Alpha]

The x value is the circumference of the planet/moon divided by how many tiles are in the level you're working with, multiplied by the (longitude in degrees)/360.

The y value is half the circumference of the planet/moon, divided by how many tiles (in y-axis) you're working with, multiplied by the Abs(latitude in degrees - 90)/180.

[john71]

So in the case of Apollo 11:

degrees N latitude degrees E longitude
Apollo 11
LRRR 0.67345 23.47307
Lunar Module 0.67416 23.47314

The moon's equatorial circumference is 10917 km.

Let's see this when we have 2 tiles:

x=(10917/2)*(23.47314/360)=5 458,5*0,0652031666666667=355,91148525

???????

What am I doing wrong?

[Shadow-Dragon-777]

I found a solution on this problem.
In Gimp, it shows the coordinates of a pixel. With Gimp you can add a grid and make it whatever size each level subdivides a world map into.
By taking the pixel coordinates of the upper left corner pixel of a tile in the grid, I can then divide the coordinates of said pixel by the grid size to get the Celestia tile number.
For example, at level9 upper left corner of Huygens tile is at 63232, 18304 on a 64K map.
level9 would display areas normally only 64 pixels on my map subdivided by 2K tiles in each level. The tile number of this tile would be
X = 63232/64 = 988
Y = 18304/64 = 286
Thus at level 9, Huygens would be in tile 988_286.

It requires math and the exact visual location of a spacecraft or other landmark on a map yes but its a method that works.

[john71]

We need the math for identifying "the" tile from only the coordinates in degrees.

So we should be able to identify "the" tile, no matter the size of the tiles and the number of levels.