Placing a texture tile on a planetary surface?

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Reiko
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Placing a texture tile on a planetary surface?

Post #1by Reiko » 14.04.2009, 10:25

I already know how to place models such as buildings etc on a planet's surface but how to I place a tile of texture? For example, I place a building at a location then how do I add a more detailed ground texture beneath it? Is there a way to do it without having to make a flat model and texturing it?
Can I place texture on a specific spot of a moon or planet and define the area it covers?

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selden
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Re: Placing a texture tile on a planetary surface?

Post #2by selden » 14.04.2009, 11:01

One way to do it on the surface of a planet or moon is to create a level 12 VT (Virtual Texture) containing a tile or two in that area.

You only need to provide tiles in the directories level0 and level12, although all of the intermediate directories need to exist.

Celestia user "Jim" wrote a utility to calculate which tile to create given a longitude and latitude, but his web site has evaporated :( Maybe someone has a copy. I don't seem to.
Selden

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jogad
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Re: Placing a texture tile on a planetary surface?

Post #3by jogad » 14.04.2009, 11:25

Hello,

If your need a very high level of detail you may have to use a big tile.
For example on the Earth, to have a resolution of about one meter by pixel, you must use a tile of 4096x4096 pixels.
But if your planet is small, smaller tiles are good for the same resolution.
You have to learn a bit about virtual textures and make a close-up.
Have a look here
http://www.lepp.cornell.edu/~seb/celestia/textures.html

French speaking people can find some documentation on virtual textures with formulas to calculate the tiles positions.
Maybe formulas are not so difficult to understand even for English speaking people.
http://www.ikiru.ch/celestia/wiki/index ... _Virtuelle
There is even links on tutorials to make close-ups with a utility to calculate the tiles and much more.
http://www.ikiru.ch/celestia/wiki/index.php/Tutoriels

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t00fri
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Re: Placing a texture tile on a planetary surface?

Post #4by t00fri » 14.04.2009, 12:05

selden wrote:One way to do it on the surface of a planet or moon is to create a level 12 VT (Virtual Texture) containing a tile or two in that area.

You only need to provide tiles in the directories level0 and level12, although all of the intermediate directories need to exist.

Celestia user "Jim" wrote a utility to calculate which tile to create given a longitude and latitude, but his web site has evaporated :( Maybe someone has a copy. I don't seem to.

Here is the tile calculator utility by Jens Meyer (aka Jim), which used to work quite well.

http://www.celestiaproject.net/~t00fri/VT-tile ... ator_2.zip

Since spring is coming on so beautifully, my obvious suspicion is that Reiko is planning to plant LOTS of blue crocus at level 12 :mrgreen: :lol:

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Topic author
Reiko
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Re: Placing a texture tile on a planetary surface?

Post #5by Reiko » 14.04.2009, 13:40

Thank you,
Still not quit understand how to create VT textures or how to place them but I will try again. :)

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Re: Placing a texture tile on a planetary surface?

Post #6by BobHegwood » 15.04.2009, 14:23

Reiko,

You can find a number of useful tutorials guides either on the Motherlode
or at Selden's home page. Have a look at the VT Guides available HERE.

Thanks, Brain-Dead
Brain-Dead Geezer Bob is now using...
Windows Vista Home Premium, 64-bit on a
Gateway Pentium Dual-Core CPU E5200, 2.5GHz
7 GB RAM, 500 GB hard disk, Nvidia GeForce 7100
Nvidia nForce 630i, 1680x1050 screen, Latest SVN

Topic author
Reiko
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Re: Placing a texture tile on a planetary surface?

Post #7by Reiko » 15.04.2009, 23:57

BobHegwood wrote:Reiko,

You can find a number of useful tutorials guides either on the Motherlode
or at Selden's home page. Have a look at the VT Guides available HERE.

Thanks, Brain-Dead
Thank you. :)


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