for celestia, version 1.3.1 , created by chris laurel
for Celestia, version 1.3.1+, created by Chris Laurel
()
Written by Don Goyette, with contributions from the Celestia developers and forum members. Editing by Selden Ball, Jr. and other Celestia forum members Version 1.0g Last revised on June 17, 2004
Table of Contents
Table of Contents.................................................................................................................... iiIntroduction............................................................................................................................ 1 Viewing This Document .............................................................................................................................................. 1 Acknowledgements ....................................................................................................................................................... 2 Disclaimer....................................................................................................................................................................... 2 Introduction .................................................................................................................................................................... 2 Symbols Used in this Guide ........................................................................................................................................ 3 Terms Used in this Guide............................................................................................................................................. 3 Argument......................................................................................................................................................................3 Data Types....................................................................................................................................................................3 Default ..........................................................................................................................................................................5 Null ...............................................................................................................................................................................5 Celestia .CEL Scripts .............................................................................................................. 6 What Is a Celestia .CEL Script?.................................................................................................................................. 6 Writing Celestia Script Commands ............................................................................................................................ 7 Comment Lines ............................................................................................................................................................8 Your First Celestia .CEL Script ...................................................................................................................................8 Coordinate Systems .............................................................................................................. 10 Celestia's Coordinate Systems................................................................................................................................... 10 Chase (Chase).............................................................................................................................................................11 Ecliptical (Follow)......................................................................................................................................................12
Equatorial (n/a)...........................................................................................................................................................13
Lock (Lock) ................................................................................................................................................................13 Universal (Free - Esc key pressed).............................................................................................................................13 Observer/Local ...........................................................................................................................................................14 Geographic (Sync Orbit) ............................................................................................................................................14 Web pages that discuss Coordinate Systems in more detail: .....................................................................................14 .CEL Script Commands ........................................................................................................ 16 .CEL Script Command Descriptions ........................................................................................................................ 16 Command Reference -- Alphabetical .........................................................................................................................16 Command Reference -- Category: Object Control and Display.................................................................................18 Command Reference -- Category: Overall Display - Rendering - Flags ...................................................................19 Command Reference -- Category: Movement - Navigation ......................................................................................20 Command Reference -- Category: Date and Time .....................................................................................................20 Alphabetical Listing of Commands............................................................................................................................21
cancel ....................................................................................................................................................................21
center .....................................................................................................................................................................21
changedistance ......................................................................................................................................................22 chase......................................................................................................................................................................22
cls ..........................................................................................................................................................................24
follow ....................................................................................................................................................................24
goto........................................................................................................................................................................25
gotoloc...................................................................................................................................................................27 gotolonglat ............................................................................................................................................................30
labels .....................................................................................................................................................................31
lock........................................................................................................................................................................32
lookback ................................................................................................................................................................33
mark ......................................................................................................................................................................33 move......................................................................................................................................................................34
orbit .......................................................................................................................................................................34
preloadtex..............................................................................................................................................................35
print .......................................................................................................................................................................36
renderflags.............................................................................................................................................................38 rotate......................................................................................................................................................................39
select......................................................................................................................................................................39
ii
set ..........................................................................................................................................................................40 setfaintestautomag45deg .......................................................................................................................................41 setframe .................................................................................................................................................................41 setorientation .........................................................................................................................................................42 setposition .............................................................................................................................................................43 setsurface...............................................................................................................................................................43 setvisibilitylimit ....................................................................................................................................................44 seturl......................................................................................................................................................................44 synchronous ..........................................................................................................................................................45 time........................................................................................................................................................................46 timerate..................................................................................................................................................................47 track.......................................................................................................................................................................47 unmark ..................................................................................................................................................................48 unmarkall ..............................................................................................................................................................48 wait........................................................................................................................................................................48 Deprecated CEL Scripting Commands ......................................................................................................................49
Document Version History.................................................................................................... 50 1.0f – Feb 2, 2004.......................................................................................................................................................50
iii
Celestia .CEL Scripting Guide
Introduction
Viewing This Document
If you downloaded this file (ie. not reading the HTML version on-line), please make sure you are reading the file with a program that fully supports the file type. For example, if this is the Word document (.doc) file, then you should be using one of the following products: , Microsoft Word
, Microsoft Word Viewer, available at
;CTT=98
, OpenOffice.org, available at
Warning: The .doc file will not display properly in WordPad.
If this file is the Rich Text Format (.rtf) file, make sure that the program you are using fully supports this format, so the file is displayed properly. For example, Windows WordPad works fine, but Windows Notepad will not display it properly. Note: URLs (links) do not function in the RTF text
file.
Here are a couple of checks to make sure the program you are using is formatting and displaying the document correctly:
1) The heading page of this guide should contain a graphic image which includes
the text "Celestia" on one line, ".CEL Scripting Guide" on the next line, with
graphics of telescopes and some space objects above and to either side of the
text.
2) Below, there should be two graphic images. The first is a Stop sign with an
open hand in it, and the second is a sticky-note with a thumb tack in it.
If you see all of these images, then it should be okay for you to continue using the document display program you are currently using.
If you do not see these images, try a different program with known support for the file type you are trying to view.
- 1 -
Celestia .CEL Scripting Guide
Acknowledgements
First, I would like to thank Chris Laurel, and the entire Celestia development team, for creating such an incredible 3-D space simulation program. If it wasn't for Chris, we'd all be doing something boring, like watching TV, or writing an e-mail to Aunt Nellie!
By the way, if you are an experienced C++ programmer with a little extra time, who has an interest in advancing Celestia to new heights, please check out the Celestia Source Forge Project page,
located at , and consider offering some of your valuable time
and experience. Celestia users seem to generate more good ideas for new features than our programmers have time to implement them!
Thank you to the folks who provided Celestia scripting information in the past: , Unknown for their Scripting.html document:
, Selden Ball, Jr. for his List of Resources for Celestia web page:
~seb/celestia/
A sincere thank you also goes to all the folks who post messages on the Celestia Forums, located at
, that relate to the topics covered in this Guide – which are many.
Your names are too numerous to list here, but we are all indebted to you for sharing your Celestia and astronomical knowledge and experience with us.
If you have not yet checked out the Celestia Forums (), you should!
They are educational, a lot of fun, and you will meet some interesting characters there too. Disclaimer
As much as I and the editors have tried to make sure the information and example code contained in this guide is correct, there are bound to be mistakes, omissions, or some things that are confusing or not explained well enough. If you happen to find one of these, please tell us about it by leaving a
message on the Celestia Scripting forum () so
we can fix it. Thank you!
Introduction
If you are new to Celestia, the best place for you to start is the Celestia User's Guide, written by
Frank Gregorio. It can be downloaded from the Celestia Documentation web page, located at
's Guide is available in the
following languages and file formats:
, English (MS Word, HTML, and Adobe PDF
, French (MS Word)
, Japanese (MS Word and Plain Text)
The Celestia User's Guide takes you on a step-by-step guided tour of Celestia and its user interface, explaining and demonstrating what many of the mouse, keyboard, and menu options do. Once you
- 2 -
Celestia .CEL Scripting Guide
are familiar with the keyboard and menu options available in Celestia, and how they function, you may want to automate some of your Celestia journeys so other folks can enjoy them too. The easiest way to do this is through Celestia's simple, built-in scripting capability called .CEL Scripting, which
is what this guide is all about.
If you find that .CEL Scripting is too easy and want more of a challenge, or if you already know another programming language, you might want to explore the Lua programming language interface to Celestia, which was introduced in version 1.3.1. This guide does not currently cover any of Lua's capabilities or how to write a Celestia script using Lua. However, you can find Lua information at , and a few example Lua scripts for Celestia at the Celestia project site on SourceForge at
In addition, Harald Schmidt has created a "Summary of Lua-support in Celestia" PDF document that
is available on his Celestia web page at , along with several
example .celx (Lua) scripts for Celestia.
Symbols Used in this Guide
Warning
Note
Terms Used in this Guide
Argument
Sometimes referred to as a variable or parameter, an argument is merely a human-readable name that is assigned to the place in your computer's memory where the value you are assigning to the argument is stored. For example, the wait command has one argument, named duration. Other
commands, like the print command, can have more than a single argument.
Data Types
A Data Type describes the type, or kind, of data that is used by the argument. The Data Types used by Celestia .CEL scripts include , , and , each of which is described in
detail below:
, This Data Type consists of any number of characters (text) enclosed in double quote
marks ( " ). For example, "Hello world." is a Data Type, and the text contained
between the quote marks is sent to the script interpreter as a .
For example:
select { object "Mars" }
Some commands require the value to be one item from a specific list of strings (text),
and will reject any other values you might assign. For example, the set command uses an
- 3 -
Celestia .CEL Scripting Guide
argument called name, which is a value, but the value must be one of the following
values:
MinOrbitSize
AmbientLightLevel
FOV
StarDistanceLimit
If you assign text to the name argument that is not one of these values, such as "Hello", you will receive a script error and the script will not run.
, This Data Type consists only of digits, the numbers 0-9. It may, or may not, include any of the following, depending on the argument:
* Decimal point
* Sign prefix ("-" for negative numbers, such as -98.53)
* Exponent suffix (such as 31.0e+15)
When you assign a value, you do not use double quote marks around the value, as is done with a value. For example, to assign a value of 5.5 to a argument, you simply enter the digits, such as:
wait { duration 5.5 }
* Do not use a negative number for the time argument. This will
freeze your Celestia display, without warning, and you will then need
to press the Esc key to reset the display.
* Do not use a negative number for the duration argument, as the
command will be ignored.
, This Data Type consists of an array (or grouping) of three individual values, enclosed within square brackets "[ ]". Each value is separated by a space (spacebar). The Data Type in Celestia, is mostly used to set 3-dimensional coordinates in space via three values that represent the X, Y, and Z Axes, from left to
right in the array. The X, Y, and Z values represent different things depending on the argument.
For example, the setposition command requires two values, base and offset.
The values shown below will position the camera outside of the Milky Way:
setposition {
base [ -64132.43 47355.11 196091.57 ]
offset [ 0 0 -1.52e-005 ] }
In some commands, a is used to specify a single X, Y, or Z axis, by entering a value of 1 in the corresponding axis position and entering a 0 in the other axis positions. For example, the up argument of the goto command uses a value for describing which axis of the selected Coordinate System you want to point "up". The example below sets the "up" axis to Y, since the represents the three axes in the [X Y Z] format:
select { object "Sol/Earth" }
goto { time 5
distance 5.5
- 4 -
Celestia .CEL Scripting Guide
upframe "follow"
up [0 1 0] }
wait ( duration 5 }
, This Data Type consists of characters copied from a Celestia Cell://URL which are
encoded in Base-64.
For example, the setposition command can use x, y, and z values from a Cell://URL that
are encoded in Base-64. The values shown below will position the camera outside of the Milky
Way:
setposition {
x "AMDCXoJK/3+IyGgR8f///w"
y "BvP2LRdAAAD/n5UGCw"
z "VUrGoeQJ+/8DyvenLQ" }
Default
A default value is the value automatically assigned to an argument by the script engine if you do not
include that argument in the command code. However, not all arguments have a default value (ie. select) so if you do not specify an argument in the command you are using, make sure it has a default value, or you will get a script error. For example, if you do not specify the duration
argument in the wait command, a value of 1.0 seconds will automatically be assigned, as in:
wait {}
Null
A null value means that no arguments are used with that command. For example, the lock command
does not accept any arguments, so it is coded as follows ...
lock {}
... with nothing between the curly braces.
- 5 -
Celestia .CEL Scripting Guide
Celestia .CEL Scripts
What Is a Celestia .CEL Script?
A Celestia .CEL script is simply a plain-text file that contains a list of instructions for Celestia to carry out automatically. For example, when a default installation of Celestia is run, the on-screen display (which will be called the camera in this guide), moves to Jupiter's moon Io. This action is
taken automatically when Celestia is run, via the included startup script, named start.cel, which
is located in the main Celestia program folder. You also may have learned that pressing the [d] key
on your keyboard runs a Demo of Celestia. This too, is a Celestia .CEL script. The filename of this script is demo.cel and it is also located in the main Celestia program folder.
You can open a Celestia script with any plain-text editor, such as Notepad, Wordpad or Word (for Windows users). Just make sure that when you save your script file to disk, that its filename uses the file extension ".cel", as this is how your computer's operating system knows the file is one of Celestia's script files, and also that you save it as a plain text file (Rich Text Format files will not work). If you are interested in seeing what a .CEL script looks like, run your favorite plain-text editor now, and open the start.cel script in Celestia's main folder.
Before modifying either of these scripts (start.cel or demo.cel),
please copy the original script files to a safe place FIRST, just in case you need them at a later date.
The start.cel script that comes with Celestia should look similar to the following:
{
select { object "Sol/Jupiter/Io" }
follow {}
goto { time 5 }
# gotolonglat { time 0 distance 1e11 longitude 0 latitude 0 }
# gotolonglat { time 0 distance 2.5 longitude -122 latitude 47 } #
Seattle!
# wait { duration 0.1 }
# orbit { axis [ 0 1 0 ] rate 10 duration 7 }
# goto { time 5 distance 10 }
# wait { duration 5.0 }
}
All of the commands and arguments shown in this script will be discussed later in this guide. If you are familiar with Celestia's keyboard commands, you should understand a lot of it just by looking at it. The select command is the same as pressing [Enter] and typing in an object name. The follow
command is the same as pressing the [f] key on your keyboard. And, the goto command is the same
as pressing the [g] key.
- 6 -
Celestia .CEL Scripting Guide
The lines that start with the "#" character are comment lines, that are not executed. When the "#"
character is removed, that line of code will be executed the next time you run the script. Chris Laurel,
the creator of Celestia, included these commented lines for user experimentation. Writing Celestia Script Commands
The very first character in a Celestia .CEL script must be an opening curly brace "{". The very last
character in a script must be a closing curly brace "}". Therefore, an empty, but valid, Celestia .CEL script file looks like the following:
{ }
That's right, the opening and closing curly braces would be the only text in the script file. However,
this script does absolutely nothing at all, which makes it pretty useless. Every script you create for
Celestia will have at least one command line in it, which is a line of text instructing Celestia to set or
do something.
A typical single Celestia script command line consists of the following pieces: , A command name, such as wait
, A space (spacebar)
, An opening curly brace {
, Zero or more argument names, such as duration, along with the value you want the argument
set to ... For example: duration 5.5 or object "Mars"
, A closing curly brace }
Here are some command line examples:
, Assign a value of 5.5, to the argument duration, in the command wait, which
tells Celestia to pause for the number of seconds you enter:
wait { duration 5.5 }
Notice there are no double quote marks (") around the value (5.5) because double
quote marks are used only to specify a value.
, Assign a value of "Mars", to the argument object, in the select command:
select { object "Mars" }
Here, double quote marks tell Celestia that a , or text value (Mars), is being sent to it.
When sending a to Celestia, the value must be enclosed in double quote marks.
Some Celestia .CEL scripting commands, such as print, send more than one argument. In these cases, you enclose all arguments and their associated values between the command's opening and
closing curly braces, such as:
print { text "Hello universe." row -4 column 1 duration 5 }
or
print { text "Hello universe."
row -4
column 1
duration 5 }
All arguments for each command must be enclosed within the command's curly braces, such as the
example above shows. You may include as much white space (spaces, blank lines, etc.) as you deem
- 7 -
Celestia .CEL Scripting Guide
necessary, and you may even specify each argument and its associated value on a different line – all
for clarity.
Comment Lines
The "#" character can be used as the first character in a script line to make that line a comment line,
which the script engine will ignore (not execute). For example:
# ---------------------------------------
# This is my Celestia script
# ---------------------------------------
select { object "Sol/Earth" }
center { time 3 }
wait { duration 3 }
# ---------------------------------------
Every line beginning with the "#" character will be ignored by Celestia's script engine (the internal
part of Celestia that reads and interprets a script file into Celestia commands).
Your First Celestia .CEL Script
The first Celestia script you create should probably be a template script (see below for an example), that contains the specific settings you want Celestia to have every time you run one of your scripts.
Actually, you don't have to create this script at all, as it has already been done for you. All you need to
do is modify it to suit your needs, once you learn more about Celestia script commands. Here is a
very short example of a template script:
{
#------------------------------------------------------------------
# Written by:
# on:
#
# The purpose of this script is ...
#------------------------------------------------------------------
# Set Celestia values (modify to meet your needs)...
#------------------------------------------------------------------
# Render the following objects...
renderflags { set "cloudmaps|planets|stars" }
# Unmark all objects...
unmarkall {}
# Set Field of View...
set { name "FOV" value 30.0 }
# Set Time Rate (1x, 100x, 1000x, etc.)...
timerate { rate 1.0 }
#------------------------------------------------------------------
# Script Body - Your code goes here ...
#------------------------------------------------------------------
#------------------------------------------------------------------
- 8 -
Celestia .CEL Scripting Guide
# End of Script - Let the user know the script is done running ...
#------------------------------------------------------------------
print { text "The script is finished."
row -3
column 25
duration 5 }
wait { duration 5 }
}
A template script saves you time because you don't have to remember or code all of the initial start-up values you want to set, in every script you write. And, the settings in the template script can be easily modified whenever you use it to begin a new script.
The example template script above also demonstrates the value of using comment lines to describe the script, who wrote it, when it was written, what the script is supposed to do, and what each section of the script code is doing. Comments are particularly useful when you want to share your scripts with other Celestia users, who did not write it, and may not fully understand what your intent was when you wrote it.
To obtain a free, much more in-depth template script, visit the Celestia Scripting Forum, located at
:
(Template Script for .cel scripts). Or visit
) and download the latest version. Don G's Celestia Page (
When you save a Celestia .CEL script file to disk, the file extension must be ".cel", which allows
your operating system to recognize the file as belonging to Celestia, and allows Celestia to know this file is one of its .CEL scripts. Also, you must save the file as plain text. Rich Text Format files do
not function in Celestia because they also contain embedded formatting information.
When you double-click on a script filename in your file browser, the operating system will automatically run Celestia (if it's not already running), which will in turn run the script file. In Microsoft Windows, this is called File Association.
The example template script above can be copied, pasted into your text editor, and then saved to a file on your computer named template.cel. Or, just download the complete, free template from Don
G's Celestia Page (). When you learn more about
Celestia .CEL scripting commands, you will want to edit your template script to setup Celestia the way you like to see things.
You now have a ready-made, beginning script that you can use whenever you want to create a new script. Simply open the template.cel file and immediately save the file as another name (File /
Save As) – and enter the name of your new script.
- 9 -
Celestia .CEL Scripting Guide
Coordinate Systems
Celestia's Coordinate Systems
The following definition is from Astronomy Answers -- Astronomical Dictionary
(~strous/AA/en/woordenboek.html#coordinate_system) ...
A Coordinate System is a tool that allows fixing of positions by measuring
distances in different directions. Those distances are the coordinates. There are
two often-used classes of coordinate systems: those that use rectangular (or
cartesian) coordinates, and those that use polar coordinates. Polar coordinates
use angles (for the direction) and one distance, and usually have a base plane that
the angles are tied to. Rectangular coordinates use only distances, measured in
mutually orthogonal directions from a common origin. Coordinate systems are
often named for the thing in or on which they measure positions, or for the base
plane or origin with which they are associated.
The names of polar coordinate systems that fix positions on a celestial body are
often made up of the Latin or Greek name of the body, followed by graphical, for
example geographical for the Earth. The names of the corresponding rectangular
coordinate systems (with the center of the body as origin) usually have the same
first part, but followed by centric, for example geocentric for the Earth,
planetocentric for planets in general, or heliocentric for the Sun.
When running Celestia interactively, you can see that it has several different modes, including
Follow, Sync Orbit, Lock, Chase, and Free (none, Esc key was just pressed). Together with one or two selected objects, these modes define a Celestia Coordinate System. In Celestia's interactive
mode, you control your exact position (longitude, latitude, orientation, orbit type, etc.) with keystrokes. In .CEL scripting, there are no interactive keystrokes, so you need to tell Celestia exactly
where you want to be located in the 3-dimensional universe, and how you want the camera to be oriented. This is where Celestia's Coordinate Systems come into play. This section describes how the X, Y, and Z, axes of each 3-dimensional Coordinate System are aligned.
Each of Celestia's interactive modes is represented by a Coordinate System in .CEL scripting, which is set via the setframe command. The following list shows each of Celestia's interactive Modes along with its corresponding Coordinate System:
Related Coordinate
Celestia Mode System (setframe)
Chase chase
Follow ecliptical
Lock lock
- 10 -
Celestia .CEL Scripting Guide
Free (none set) universal
Sync Orbit geographic
n/a equatorial
n/a observer/local (both used in code and Bookmarks)
Below, is a brief description of the Coordinate Systems Celestia uses, which you will find helpful when using the goto, gotoloc, gotolonglat, and setframe commands. You may want to skip
this section until you actually have a need to select a Coordinate System in your script, then come back here to learn more about how each system is aligned.
All of Celestia's Coordinate Systems are orthonormal, meaning that the X, Y, and Z axes are all at
right angles to each other and all have unit length (there is no stretching).
Chase (Chase)
The Chase Coordinate System (which is also a .CEL script command) tells Celestia to chase the
currently selected object through space, which keeps your orientation constant with respect to the direction in which an object is moving. This Coordinate System is similar to lock (explained
below), except that the Z axis points in the direction of motion relative to the target object's parent
body (the Sun for planets, a planet for moons). The keyboard command for chase is the quote
mark ["].
In Chase mode, your position remains fixed relative to the target's direction of motion. If you're directly in front of or behind the target (in terms of its motion), you'll remain there regardless of how it moves. In the case of the Moon, Chase is similar to Sync Orbit mode (Geographic Coordinate System, although the Moon wobbles around quite a bit) because the Moon's direction of motion is nearly fixed with respect to its surface, in terms of longitude, at least.
Try Chase mode with a comet other than Halley. Because comets generally have highly eccentric orbits, the direction of motion will not always be almost perpendicular to the direction to the Sun. In Lock mode the Sun will stay fixed, but it will drift across the field of view in Chase mode.
Note: When you click any of the example links below, if Celestia is not currently running, the program will be started. Celestia will then be directed to display the scene as described in a saved Cell://URL. All of the visual, on-screen examples in this guide are presented in this manner, as saved Cell://URLs. If the file format you are using does not support these links (ie. does not run Celestia or display these scenes), copy the Cell://URL text and then paste it into the Address bar of your browser.
Here is a "Chase Moon" example with the Earth in view and time sped up.
cel://Chase/Sol:Earth:Moon/2003-08-21T06:52:13.46379?x=MEnpHzvMcjbLDA
&y=bGaLyzeEfg&z=tSb1nY+r83gI&ow=0.134317&ox=-0.116625&oy=-0.982872&oz
=-0.048167&select=Sol:Earth:Moon&fov=11.232885&ts=10000.000000<d=0&
rf=2711&lm=49152
Here is an example of chasing the International Space Station as it passes over the southwest
U.S.A.
- 11 -
Celestia .CEL Scripting Guide
cel://Chase/Sol:Earth:ISS/2003-08-18T18:22:00.50613?x=Rxar44rgPtTKDA&y=Hm5zfcxKFg&z=5S0VG5mqnxcJ&ow=-0.014557&ox=0.125254&oy=0.991866&oz=0.017389&select=Sol:Earth:ISS&fov=20.172722&ts=10.000000<d=0&rf=2711&lm=49216
A closer view of the ISS.
cel://Chase/Sol:Earth:ISS/2003-08-18T16:37:40.92238?x=QO/LBT1WltHKDA&y=BZ8v5eYeHA&z=eIK69cCeARwJ&ow=-0.162169&ox=0.470633&oy=0.847726&oz=0.183212&select=Sol:Earth:ISS&fov=83.034142&ts=10.000000<d=0&rf=2967&lm=49152
Following the ISS provides quite a different perspective,
cel://Follow/Sol:Earth:ISS/2003-08-19T00:24:04.39120?x=CXQ5i5ZQ9t3KDA&y=21xfnfIhGg&z=ANUFePvmhAkJ&ow=-0.719911&ox=-0.444001&oy=0.511589&oz=0.151222&select=Sol:Earth:ISS&fov=68.312462&ts=100.000000<d=0&rf=2967&lm=49216
while locking ISS and Earth is similar to Chasing ISS.
cel://PhaseLock/Sol:Earth:ISS/Sol:Earth/2003-08-18T18:18:31.55462?x=UU5NeFeULtTKDA&y=OAawihL8Fg&z=mMJ0Da9JARgJ&ow=-0.034557&ox=-0.179894&oy=0.968668&oz=0.167710&select=Sol:Earth&fov=96.122467&ts=10.000000<d=0&rf=2967&lm=49216
Ecliptical (Follow)
The Ecliptical Coordinate System tells Celestia to follow the selected object. As the object moves through space, the camera moves with it. The object can rotate on its axis below you, which
means the longitude will constantly change – but you will remain the same distance and latitude above the object. The keyboard command for follow is the [f] key.
The X axis points away from the Sun in the direction of the Julian 2000.0 vernal equinox. The Y
axis is normal to the ecliptic with positive Y north. The Z axis completes the right-handed
coordinate system.
Example: Moon orbiting Earth (starting from the lower right corner). cel://Follow/Sol:Earth/2003-09-08T15:36:16.17625?x=IGbgoHFF/RPNDA&y=6sEjCL2tNQ&z=TZe8QsgxgPkD&ow=0.590026&ox=0.108706&oy=0.797316&oz=-0.065877&select=Sol:Earth&fov=25.745958&ts=10000.000000<d=0&rf=2711&lm=49152
Another example of how Ecliptical/Follow works: Follow Earth with Orbits displayed.
cel://Follow/Sol:Earth/2003-09-12T02:43:49.61548?x=AAAlIfvXfCK4DA&y=Xg1baTz60mG4&z=VSokNenF8cm6/////////w&ow=0.365811&ox=0.459924&oy=0.685501&oz=0.429815&select=Sol:Earth&fov=25.745955&ts=1000000.000000<d=0&rf=2743&lm=49154
Using the Ecliptical Coordinate System on our sun (Sol), allows you to watch the planets orbit the sun.
cel://Follow/Sol/2006-09-08T13:07:56.45071?x=AADER1J42VPWDA&y=CkwO3rHqa8Q2&z=VcpAbDhE8G9k/////////w&ow=-0.141244&ox=-0.566118&oy=0.806803&
- 12 -
Celestia .CEL Scripting Guide
oz=0.092897&select=Sol&fov=25.745993&ts=1000000.000000<d=0&rf=2743&lm=49154
Equatorial (n/a)
??? This Coordinate System is selectable in the setframe command but is not available as a keystroke command.
Lock (Lock)
As when running Celestia interactively, this coordinate system involves two objects – the first
object selected is called the reference object, and the second is called the target object. When
two objects are locked together as a pair, as you rotate the scene, the target object stays locked to
the reference object, and the distance displayed is the distance between the two objects. The
keyboard command for lock is the colon [:].
The Z axis points from the reference object (first object selected) to the target object; the Y axis
lies in the plane defined by the Z axis and the rotation axis of the reference object, at a right angle
to the Z axis. The X axis completes the right-handed coordinate system.
In Lock mode, your position remains fixed relative to a line between the reference object and the
target object. As the target object moves around the reference object (relatively speaking) so do
you. Thus if the target object is Sol, the illuminated fraction of the reference object (its "phase")
remains the same because you're moving around the object in sync with Sol.
From the developers: Unfortunately, this definition does not work
when the rotation axis is perfectly aligned with the reference to target
direction. It also produces strange results with precessing objects. We are looking into changing it so that this Coordinate System is defined by
the axis of precession instead of the axis of rotation.
Example: Lock Earth-Moon showing Moon Phases. Earth is the reference object and Moon is the
target object.
cel://PhaseLock/Sol:Earth/Sol:Earth:Moon/2003-08-17T01:32:18.13069?x=8Fk2UN0+TJHKDA&y=vkY4eIHMOw&z=RdFCjP5pPHgJ&ow=0.808591&ox=0.166290&oy=0.535185&oz=-0.179180&select=Sol:Earth:Moon&fov=11.232886&ts=100000.000000<d=0&rf=2711&lm=49152
Another example using Earth as the reference object, but Sol as the target. cel://PhaseLock/Sol:Earth/Sol/2007-08-28T06:59:21.22591?x=AKS7pOkuDy3MDA&y=zLG9Rjcl&z=1drjcBB3a+oG&ow=0.824363&ox=0.118785&oy=-0.520150&oz=0.189101&select=Sol:Earth:Moon&fov=1.595636&ts=1000.000000<d=1&rf=35735&lm=49156
Universal (Free - Esc key pressed)
Setting the Coordinate System to universal de-selects the current Coordinate System and places Celestia into free (or absolute) mode, which is what happens when you press the [Esc] key on the
- 13 -
Celestia .CEL Scripting Guide
keyboard. This mode is not time dependent – a given position (using one of the goto commands)
will always place you at the same point in space regardless of the current simulation time. Observer/Local
??? This Coordinate System is selectable in the setframe command but is not available as a
keystroke command.
Geographic (Sync Orbit)
The Geographic Coordinate System allows you to remain in a stationary, or geosynchronous
orbit above the selected object (not just Earth). As the object rotates below, the camera moves with it, as if it were attached to the object. The keyboard command for Sync Orbit is [y].
In the Geographic Coordinate System, the axes rotate with the selected object. The Y axis is the
axis of rotation – counter-clockwise, so it points north for prograde rotators like Earth, and south for retrograde rotators like Venus. The X axis points from the center of the object to the intersection of its zero longitude meridian and equator. The Z axis (at a right angle to the XY plane) completes the right-handed coordinate system. An object with constant geographic coordinates will thus remain fixed with respect to a point on the surface of the object.
The origin of all Celestia Coordinate Systems, except universal, is
the center of the reference object. For example, if you are following
Mercury and execute a gotoloc command with a position of [0 0
0], you will travel to the center of Mercury. In universal mode, [0 0
0] is a location near the Sun (Sol).
The position argument in gotoloc is a point in the current
Coordinate System specified in units of kilometers.
Web pages that discuss Coordinate Systems in more detail:
Astronomy Answers -- Astronomical Dictionary (text only):
~strous/AA/en/woordenboek.html#coordinate_system
Coordinate Systems Overview (text and graphics):
Celestial Coordinate System (text and graphics):
Coordinate Systems in Astronomy (text and graphics):
~teacha/130_manual/node9.html
Earth Coordinate System (text and graphics):
~js/ast121/lectures/lec02.html
- 14 -
Celestia .CEL Scripting Guide
Beyond Our Skies: Discovering the Cosmos -- Coordinate Systems (text and graphics):
Coordinate system transformation (equations and graphics): ~pbourke/projection/coords/
- 15 -
Celestia .CEL Scripting Guide
.CEL Script Commands
.CEL Script Command Descriptions
This section lists all Celestia .CEL script commands, as of version 1.3.1, along with a description of what each command does, what its arguments are, default argument values, valid values for the arguments (if any exist), and examples of how to code the command.
Remember, experimentation can be the most enjoyable part of learning, so please take your time and experiment with each of the commands. If you discover a particularly interesting effect when implementing a series of commands, please, by all means, share it with all the other Celestia users in the Celestia Scripting Forum ().
The first part of this section provides an alphabetical reference list of script commands, and a
categorized list, by the type of command.
* All Celestia script commands must be entered in lower-case only, as shown, or
they will not be recognized by Celestia. You should also enter all argument names in
lower-case only, even though some are not case sensitive.
* When you code a command that includes a time or duration argument, such as
goto, print, center, etc., you must include a wait command after it, with a
duration equal to or greater than the length of time used in the command. If you
forget to do this, the command may be ignored or may not function as you intend.
Command Reference -- Alphabetical
cancel Cancels goto and track commands, and resets the
Coordinate System to universal.
center Center the currently selected object in the display.
changedistance Change your distance from the selected object.
chase Set the Coordinate System to chase.
cls Clear the display screen of all text printed using the
print command.
follow Follow the currently selected object – Sets the Coordinate
System to ecliptical.
goto Go to the currently selected object using the current
Coordinate System.
- 16 -
Celestia .CEL Scripting Guide gotoloc Go to the specified position and orientation of the
currently selected object using the current Coordinate
System.
gotolonglat Go to the specified longitude and latitude of the
selected object.
labels Set or clear labels to be displayed.
lock Lock two objects together in the camera's view. Sets the
Coordinate System to lock.
lookback Change the current camera view by 180 degrees. mark Mark the defined object with the specified symbol. move Move the camera at the specified velocity.
orbit Orbit the currently selected object using the current
Coordinate System.
preloadtex Pre-load a texture file from disk to memory. print Display a text message on the display screen. renderflags Set or clear items to be rendered/displayed on-screen. rotate Rotate the camera view.
select Select an object (planet, moon, galaxy, etc.). set Set the Min Orbit Size, Ambient Light Level, Field Of
View, Star Distance Limit, or Star Style.
setfaintestautomag45deg Set the Magnitude of stars to be displayed when
Auto-Magnitude is ON.
setframe Set the Coordinate System to be used.
setorientation Set the camera's orientation.
setposition Set the camera's position in space.
setsurface Set the name of an alternative surface for the selected
object.
setvisibilitylimit Set the Magnitude of stars to be displayed when
Auto-Magnitude is OFF.
seturl Move the camera to the location of a saved "location
URL" (or Cell://URL).
synchronus Orbit the currently selected object in Synch Orbit mode.
Sets the Coordinate System to geographic. time Set the date and time in JulianDay format.
timerate Set the time multiplication factor, ie. 100x.
track Keep the currently selected object centered in the display. unmark Unmark the specified object.
unmarkall UnMark all objects and disable the display of Marks. wait Pause script execution for the specified number of
seconds.
- 17 -
Celestia .CEL Scripting Guide Below, is a categorized listing of script commands that should help you find the type of command you need, with some commands being listed in multiple categories. Each category is separated by a
page-break in case you want to print them out on paper:
Command Reference -- Category: Object Control and Display
center Center the currently selected object in the display.
chase Set the Coordinate System to chase.
follow Follow the currently selected object – Sets the Coordinate
System to ecliptical.
lock Lock two objects together in the camera's view. Sets the
Coordinate System to lock.
lookback Change the current camera view by 180 degrees.
orbit Orbit the currently selected object using the current
Coordinate System.
rotate Rotate the camera view.
select Select an object (planet, moon, galaxy, etc.).
setframe Set the Coordinate System to be used.
setorientation Set the camera's orientation.
setposition Set the camera's position in space.
setsurface Set the name of an alternative surface for the selected
object.
seturl Move the camera to the location of a saved "location
URL" (or Cell://URL).
synchronus Orbit the currently selected object in Synch Orbit mode.
Sets the currently active Coordinate System to
geographic.
track Keep the currently selected object centered in the display.
- 18 -
Celestia .CEL Scripting Guide
Command Reference -- Category: Overall Display - Rendering - Flags
cls Clear the display screen of all text printed using the
print command.
labels Set or clear labels to be displayed.
lookback Change the current camera view by 180 degrees. mark Mark the defined object with the specified symbol. preloaxtex Pre-load a texture file from disk to memory. print Display a text message on the display screen. renderflags Set or clear items to be rendered/displayed on-screen. set Set the Min Orbit Size, Ambient Light Level, Field Of
View, Star Distance Limit, or Star Style. setfaintestautomag45deg Set the Magnitude of stars to be displayed when
Auto-Magnitude is ON.
setframe Set the Coordinate System to be used. setsurface Set the name of an alternative surface for the selected
object.
setvisibilitylimit Set the Magnitude of stars to be displayed when
Auto-Magnitude is OFF.
unmark Unmark the specified object.
unmarkall UnMark all objects and disable the display of Marks.
- 19 -
Celestia .CEL Scripting Guide
Command Reference -- Category: Movement - Navigation
cancel Cancels goto and track commands, and resets the
Coordinate System to universal.
center Center the currently selected object in the display.
changedistance Change your distance from the selected object.
chase Set the Coordinate System to chase.
follow Follow the currently selected object – Sets the currently
active Coordinate System to ecliptical.
goto Go to the currently selected object using the current
Coordinate System.
gotoloc Go to the specified position and orientation of the
currently selected object using the current Coordinate
System.
gotolonglat Go to the specified longitude and latitude of the
selected object.
lookback Change the current camera view by 180 degrees.
move Move the camera at the specified velocity.
orbit Orbit the currently selected object using the current
Coordinate System.
rotate Rotate the camera view.
setframe Set the Coordinate System to be used.
setorientation Set the camera's orientation.
setposition Set the camera's position in space.
seturl Move the camera to the location of a saved "location
URL" (or Cell://URL).
synchronus Orbit the currently selected object in Synch Orbit mode.
Sets the currently active Coordinate System to
geographic.
track Keep the currently selected object centered in the display.
Command Reference -- Category: Date and Time
time Set the date and time in Julian Date or UTC format.
timerate Set the time direction (forward or backward) and set the
time multiplication factor (ie. 100x).
wait Pause script execution for the specified number of
seconds.
- 20 -
Celestia .CEL Scripting Guide Alphabetical Listing of Commands
cancel
(null)
Cancels goto and track commands, and resets the Coordinate System to universal, which means it also cancels follow, synchronous and other Coordinate System related commands.
This command is much like pressing the ESC key when running Celestia in its interactive mode.
When moving from one object to another, it's a good idea to use the cancel command between them, in order to release any functional hold that exists on the currently selected object. If you
want to maintain your current Coordinate System setting (if other than universal), you will need to reset it via the setframe command after executing the cancel command.
For example, the first part of this script selects the Earth, goes to it, and then performs other
commands, maybe to change it's view, speed up time, etc. The second section executes a cancel command, selects Mars, and then performs other commands on Mars:
select { object "Sol/Earth" }
goto { time 3 }
wait ( duration 3 }
# ...
#
# ...
cancel { }
select { object "Sol/Mars" }
goto { time 3 }
wait { duration 3 }
# ...
#
# ...
If the currently selected object has follow enabled, then it will be automatically overridden by selecting and following a new object.
If the currently selected object has track enabled, as of Celestia version 1.3.1 you can use the
following code to cancel only a track command:
select { object "" }
track { }
center
time (default 1.0)
Centers the currently selected object in the display. You must first use the select command to select an object to be centered.
- 21 -
Celestia .CEL Scripting Guide
time Number of seconds to take centering the object.
Do not use a negative number for the time argument. This will freeze your
Celestia display, without warning, and you will then need to press the Esc key to reset the display.
The following example selects the Earth and takes 5-1/2 seconds to center it on the screen. If you
do not see the Earth, press the "g" key on your keyboard and you should see the Earth zoom into
view from the center of the display:
select { object "Sol/Earth" }
center { time 5.5 }
changedistance
duration (default 1.0)
rate (default 0.0)
Changes the camera's distance from the currently selected object. You must first use the select
command to select an object.
duration Number of seconds to take when changing the distance.
rate Speed at which to change the distance. Small values work best, from
decimal values, to 5 or 6. A negative value moves the camera closer to the
object, while a positive value moves the camera further away ("+" sign is
not necessary).
Do not use a negative number for the duration argument, as the
command will be ignored.
The following example selects the Earth, travels to it, and then spends 2-1/2 seconds changing
your display distance to be further away from the Earth: select { object "Sol/Earth" }
goto { time 3 }
wait { duration 3 }
changedistance { duration 2.5 rate 0.5 }
wait { duration 2.5 }
chase
(null)
Tells Celestia to set the active Coordinate System to chase, which chases the currently selected
object through space (please refer to the Coordinate Systems section earlier in this guide). This
keeps your orientation constant with respect to the direction in which an object is moving. This
Coordinate System is similar to lock (please see below), except the Z axis points in the direction
- 22 -
Celestia .CEL Scripting Guide
of motion relative to the target object's parent body (the Sun for planets, a planet for moons). The keyboard command for chase is the double quote mark ["].
In Chase mode, your position remains fixed relative to the target's direction of motion. If you're directly in front of or behind the target (in terms of its motion), you'll remain there regardless of how it moves. In the case of the Moon, Chase is similar to Sync Orbit mode (Geographic Coordinate System, although the Moon wobbles around quite a bit) because the Moon's direction of motion is nearly fixed with respect to its surface, in terms of longitude, at least.
Try Chase mode with a comet, other than Halley. Because comets generally have highly eccentric orbits, the direction of motion will not always be almost perpendicular to the direction to the Sun. In Lock mode the Sun will stay fixed, but it will drift across the field of view in Chase mode.
* Before using the chase command, you must first use the select command to
select an object.
Only one Coordinate System can be active at any given time:
, chase (Chase)
, equatorial , ecliptical (Follow)
, geographic (Sync Orbit)
, lock (Lock)
, observer
, universal (Free – ie. Esc key pressed)
The following example selects the Moon, sets the Coordinate System to chase, and then goes to
the Moon:
select { object "Sol/Earth/Moon" }
chase { }
goto { time 2 }
wait { duration 2 }
The following Cel:/URLs (links that display pre-defined scenes on your Celestia program)
demonstrate a couple views of Earth, from the Moon, with the Moon set to chase:
Chase Moon, with Earth in view
cel://Chase/Sol:Earth:Moon/2003-09-29T02:24:01.65592?x=NmgtqSucTmfNDA
&y=Dawu7ij5HA&z=J0zEiSliAYP+/////////w&ow=0.936040&ox=0.018333&oy=0.3
47256&oz=0.053905&select=Sol:Earth:Moon&fov=25.000031&ts=10000.000000
<d=0&rf=2711&lm=49152
Chase Moon with Earth and Sun
cel://Chase/Sol:Earth:Moon/2004-06-18T23:52:25.45421?x=4O/tRdjxFRe9DA
&y=Gjek9BgxYv7//////////w&z=VVoLa31FBhcQ&ow=-0.989363&ox=0.047153&oy=
-0.113197&oz=0.078252&select=Sol:Earth:Moon&fov=25.745911&ts=100000.0
00000<d=0&rf=2967&lm=49156
- 23 -
Celestia .CEL Scripting Guide
cls
(null)
Clears the display screen of any left-over text that was printed via the print command.
Personally, I have not found a need to use this command in any of the scripts I have written.
Example:
cls { }
follow
(null)
This command tells Celestia to set the Coordinate System to ecliptical, and to follow the
currently selected object (please refer to the Coordinate Systems section earlier in this guide). As the object moves through space, the camera moves with it. The object can rotate on its axis, which means the longitude will constantly change, but the camera will remain the same distance and latitude above the object.
The X axis points away from the Sun in the direction of the Julian 2000.0 vernal equinox. The Y axis is normal to the ecliptic with positive Y north. The Z axis completes the right-handed coordinate system.
You must first use the select command to select an object to be followed.
Only one Coordinate System can be active at any given time:
, chase (Chase)
, equatorial
, ecliptical (Follow)
, geographic (Sync Orbit)
, lock (Lock)
, observer
, universal (Free – ie. Esc key pressed)
When you follow Earth, this coordinate system makes Earth the center of the solar system, where the Sun revolves around the Earth: Cell://URL Follow Example.
This example selects Mars, sets the Coordinate System to ecliptical (follow), and then travels to
Mars:
select { object "Sol/Mars" }
follow { }
goto { time 2 }
wait { duration 2 }
- 24 -
Celestia .CEL Scripting Guide
goto
time (default 1.0)
distance (default 5.0)
upframe (default "observer")
up (default [0 1 0] "Y")
Moves the camera to the currently selected object, taking time seconds, stopping distance
from the object, using the upframe Coordinate System, and defining the axis that points up. You
must first use the select command to select an object.
time The number of seconds to take going to the object.
distance Describes how far away from the object you want to be positioned, in units
of the object's radius, plus 1. For example, if the object's radius is 10000
km, and you specify 6 for distance, you will be positioned 50000 km
from the object's center.
An easy way to compute this value is: distance = distance you want to be
from the object, divided by the object's radius, plus one.
For example, if you want to be 1,000,000 km from Earth, which has a radius
of 6,378.1 km, then the calculation is:
(1000000 / 6,378.1) + 1 = 157.7865
Special distance values:
0 (zero) = Center of the object. In version 1.3.1, using this value causes the
program to incorrectly recognize further positioning values, so do not use
zero.
1 = Surface of the object. Traveling to the exact surface level of an object
may cause some graphics cards to display random polygons on the display
screen, so it is best to use a value slightly above the surface.
upframe Sets the specified Coordinate System, which must be one of the following
values (for more information, refer to the Coordinate System descriptions
earlier in this guide):
, chase
, ecliptical
, equatorial
, geographic
, lock
, observer
, universal
up Defines which axis points up, X [1 0 0], Y [0 1 0] or Z [0 0 1].
- 25 -
Celestia .CEL Scripting Guide
Do not use a negative number for the time argument. This will freeze
your Celestia display, without warning, and you will then need to press the Esc key to reset the display.
* Before using the goto command, you must first use the select
command to select an object.
* You can use other non-movement commands, such as print, while the
camera is moving towards its destination.
* Before using other commands that have a time argument, you must
execute a wait command with a duration equal to or greater than the value
of the goto command's time argument. Otherwise, the camera will not
execute the goto command, but will instead execute the next time-based
command.
The following example selects Mars and takes five seconds to travel there:
select { object "Mars" }
goto { time 5 }
wait { duration 5 }
Invalid example -- The following is an example of how not to perform a time-based command in Celestia. One might assume that this series of commands would select Mars, taking five seconds to get there; then select Earth and take three seconds to get there. However, since the
required wait command was not performed after the first goto command, Celestia ignores the first goto command and executes only the second one. You would only see Earth, and not Mars.
select { object "Mars" }
goto { time 5 }
select { object "Earth" }
goto { time 3 }
wait { duration 8 }
The correct way to script the above example is as follows: select { object "Mars" }
goto { time 5 }
wait { duration 5 }
select { object "Earth" }
goto { time 3 }
wait { duration 3 }
The next example shows how a non-movement command can be used after a goto command, by displaying a message on the screen while Celestia is going to Mars:
select { object "Mars" }
goto { time 5
distance 8.5
upframe "follow"
up [0 1 0] }
- 26 -
Celestia .CEL Scripting Guide print { text "We're on our way to Mars."
row -3 column 1
duration 5 }
wait { duration 5 }
gotoloc
time (default 1.0)
position (default [0 1 0])
xrot (default 0.0)
yrot (default 0.0)
zrot (default 0.0)
-or-
time (no default)
x (no default)
y (no default)
z (no default)
ow (no default)
ox (no default)
oy (no default)
oz (no default)
The gotoloc command moves the camera to the currently selected object, taking time seconds, traveling to the specified position (or the Base64 values x, y, and z from a Cell://URL), using the orientation specified via xrot, yrot, and zrot (or ow, ox, oy, and oz). You must first use the select command to select an object. (Note: gotoloc does not reset the coordinate system. It retains the previously set coordinate system.)
If you are attempting to duplicate a position based on a Cell://URL, you will also need to set the
proper Coordinate System, position, and other parameters. (Also see seturl.)
The x, y, and z values represent position as stored by a Cell://URL. The ow, ox, oy and oz
values represent orientation (xrot, yrot, and zrot) as stored by a Cell://URL. These values are
obtained from the following Cell://URL values:
?x= &y= &z= and &ow= &ox= &oy= &oz=
time The number of seconds to take going to the object.
- 27 -
Celestia .CEL Scripting Guide position Defines a point in the current Coordinate System specified in units of
kilometers. For all but the universal Coordinate System, a position of
[ 0 0 0 ] is the center of the object.
The first value represents the camera location, in kilometers, along the X
axis.
The second value represents the camera location, in kilometers, along the Y
axis.
The third value represents the camera location, in kilometers, along the Z
axis.
The kilometer value you specify must include the radius of the object. For
example, if you want to be positioned 100,000 km above the surface of the
Earth, which has a radius of 6378.1 km, you would add the radius of the
Earth to your desired altitude of 100,000 km, which results in a position
value of 106378.1 (see example below).
xrot xrot, yrot, and zrot are the "Eular Angle" or "Angle-Axis" yrot representation of the camera's orientation. Think of them as Pitch, Yaw, and zrot Roll in aviation. These are used to control which direction the camera is
looking. The related keyboard commands are as follows:
X/Pitch (Up/Down Arrow)
Y/Yaw (with NumLock on: Keypad #4 and Keypad #6)
Z/Roll (Left/Right Arrow)
Do not use a negative number for the time argument. This will freeze
your Celestia display, without warning, and you will then need to press the Esc key to reset the display.
The following example displays the Earth 100,000 kilometers away:
select { object "Sol/Earth" }
center { }
follow { }
gotoloc { time 2
position [0 106378.1 0]
xrot 90
yrot 0
zrot 0 }
wait { duration 2 }
The next example is a bit more complex and demonstrates both gotoloc methods. It travels to the Earth, setting a position so you can see the night lights over the USA, view the Sun in the
upper left hand corner of the display, and the Moon in the upper right hand corner:
{
cancel { }
- 28 -
Celestia .CEL Scripting Guide
renderflags { clear "boundaries|comettails|constellations" }
renderflags { clear "eclipseshadows|orbitspointstars|ringshadows" }
renderflags { clear "automag|grid" }
renderflags { set "cloudmaps|galaxies|nightmaps|planets|stars" }
renderflags { set "atmospheres|markers" }
labels { clear "planets|moons|spacecraft|asteroids" }
labels { clear "constellations|stars|galaxies" }
# Pause time and set the date and time...
timerate { rate 0 }
time { jd 2452874.692638889 }
# Place a blue square marker around the Moon...
unmarkall { }
mark { object "Sol/Earth/Moon"
size 20.0
color [0 0 1]
symbol "square" }
# Set the Field Of View...
set { name "FOV" value 47.0 }
select { object "Sol/Earth" }
center { }
follow { }
# Goto location: +7000km-X, +9000km-Y, +11000km-Z # Pitch Up +13X, Yaw Left -32Y, Roll Left -95Z
gotoloc { time 2
position [7000 9000 11000]
xrot 13
yrot -32
zrot -95 }
wait { duration 2 }
print { text "Blue square is the Moon ---"
row -24 column 32 duration 3 }
wait { duration 3 }
#******************************************
print { text "First result done."
duration 2 row -3 column 2 }
wait { duration 2 }
#******************************************
cancel { }
gotoloc {
time 2
x "wJjebddBM3XLDA"
y "Z2/b0Q34Pw"
z "GShiyVOKuxUI"
ow 0.954531
- 29 -
Celestia .CEL Scripting Guide
ox 0.112769
oy -0.272262
oz -0.045019 }
#******************************************
print { text "Second result done."
duration 2 row -3 column 2 }
wait { duration 2 }
#******************************************
}
gotolonglat
time (default 1.0)
distance (default 5.0)
up (default Y [0 1 0])
longitude (no default)
latitude (no default)
Go to the currently selected object, taking time seconds, stopping distance from the object,
using up orientation, positioning yourself above the specified longitude and latitude
surface coordinates. (Note: gotoloc does not reset the coordinate system. It retains the previously set coordinate system.)
time The number of seconds to take going to the object.
distance Describes how far away from the object you want to be positioned, in units
of the object's radius, plus 1. For example, if the object's radius is 10000
km, and you specify 6 for distance, you will be positioned 50000 km
from the object's center.
An easy way to compute this value is: distance = distance you want to
be from the object, divided by the object's radius, plus one.
For example, if you want to be 1,000,000 km from Earth, which has a
radius of 6,378.1 km, then the calculation is:
(1000000 / 6,378.1) + 1 = 157.7865
Special distance values:
0 (zero) = Center of the object. In version 1.3.1, using this value causes the
program to incorrectly recognize further positioning values, so do not use
zero.
1 = Surface of the object. Traveling to the exact surface level of an object
may cause some graphics cards to display random polygons on the display
screen, so it is best to use a value slightly above the surface.
up Defines which axis points up, X [1 0 0], Y [0 1 0] or Z [0 0 1].
- 30 -
Celestia .CEL Scripting Guide
longitude These two values describe the surface coordinates you want to be
latitude positioned above, and should be specified as decimal values.
Longitude is specified as a negative number for the Western hemisphere
and as a positive number for the Eastern hemisphere ("+" sign is not
necessary).
Latitude is specified as a negative number for the Southern hemisphere,
and as a positive number for the Northern hemisphere ("+" sign is not
necessary).
time argument. This will freeze Do not use a negative number for the
your Celestia display, without warning, and you will then need to press the Esc key to reset the display.
gotolonglat command, you must first use the * Before using the
select command to select an object.
* You can use other non-movement commands, such as print, while the
camera is moving towards its destination.
* Before using other commands that have a time argument, you must
execute a wait command with a duration equal to or greater than the value
of the goto command's time argument. Otherwise, the camera will not
execute the goto command, but will instead execute the next time-based
command.
This example selects the Earth and positions the camera over Seattle, Washington, USA:
select { object "Sol/Earth" }
synchronous { }
gotolonglat { time 5
distance 3
up [0 1 0]
longitude -122
latitude 47 }
print { text "Traveling to Seattle, Washington, USA."
row -3 column 1 duration 5 }
wait { duration 5 }
print { text "Hovering over Seattle, Washington, USA."
row -3 column 1 duration 5 }
wait { duration 5 }
labels
set (no default)
clear (no default)
- 31 -
Celestia .CEL Scripting Guide
Set (turn on) or clear (turn off) labeling of one or more of the items below. The set and
clear string values can be any combination of the following items. Multiple values are specified
within a single set of quotes (") by separating them with a vertical bar "|" (ie. "moons|stars"):
, asteroids
, comets
, constellations
, galaxies
, moons
, planets
, spacecraft
, stars
The following two examples demonstrate how to clear and set labels:
labels { clear "comets|constellations|galaxies|stars" }
labels { set "asteroids|moons|planets|spacecraft" }
lock
(null)
This command locks two objects together (please refer to the Coordinate Systems section earlier in this guide). As when running Celestia interactively, this coordinate system involves two objects
– the first object selected is called the reference object, and the second object selected is called the target object. When two objects are locked together as a pair, as you rotate the scene, the target object stays locked to the reference object, and the distance displayed is the distance
between the two objects.
The Z axis points from the reference object (first object selected) to the target object; the Y axis
lies in the plane defined by the Z axis and the rotation axis of the reference object, at a right angle
to the Z axis. The X axis completes the right-handed coordinate system.
In Lock mode, your position remains fixed relative to a line between the reference object and the
target object. As the target object moves around the reference object (relatively speaking) so do
you. Thus if the target object is Sol, the illuminated fraction of the reference object (its "phase")
remains the same because you're moving around the object in sync with Sol.
Only one Coordinate System can be active at any given time:
, chase (Chase)
, equatorial
, ecliptical (Follow)
, geographic (Sync Orbit)
, lock (Lock)
, observer
, universal (Free – ie. Esc key pressed)
- 32 -
Celestia .CEL Scripting Guide The example below will maintain your position with respect to the center of the Earth, and keep
both the Sun (Sol) and the Earth at a fixed location in the camera view. It's the same as if you
typed the following keys on your keyboard: "3 f 0 :" (0 is a zero).
select { object "Sol/Earth" }
follow { }
select { object "Sol" }
lock { }
lookback
(null)
Change the current camera view by 180 degrees (like a rear-view mirror).
Example:
lookback { }
mark
object (no default)
size (default 10.0)
color (default [1 0 0] - Red)
symbol (default "diamond")
This command marks the object with the specified symbol of the specified size and color.
object Name of the object to be marked.
size Diameter, in pixels, of the symbol.
color Defines the color of the symbol. The three number values define the strength of
Red, Green and Blue (RGB) respectively. Allowable values are from 0 to 1,
with decimals being specified with a leading 0, such as 0.5. Any value over 1 is
handled the same as if it were specified as 1. Here are some example color
values:
Black: [0 0 0]
Red: [1 0 0] (default)
Green: [0 1 0]
Blue: [0 0 1]
Yellow: [1 1 0]
White: [1 1 1]
- 33 -
Celestia .CEL Scripting Guide
symbol Defines what shape of symbol to mark the object with, which must be one of
the following string values:
* diamond (default)
* plus
* square
* triangle
* x
If the object to be marked was previously marked, or if you are unsure, you
unmark the object first. must
The following example marks the Earth with a green "x": unmark { object "Sol/Earth" }
mark { object "Sol/Earth"
size 15
color [0 1 0]
symbol "x" }
move
duration (no default)
velocity (no default)
Move the camera at the specified velocity for the specified duration. A wait command is not necessary after a move command.
duration Number of seconds to take during the move.
velocity Speed, in km/second for each of the X, Y and Z axes, as defined for the
currently active coordinate system. Positive and negative values are used to
indicate forward and reverse respectively ("+" sign is not necessary for
positive values).
Do not use a negative number for the duration argument, as the
command will be ignored.
This example moves the camera along the X axis for 10 seconds at a speed of 100,000 km/second:
move { duration 10 velocity [ 100000 0 0 ] } orbit
duration (default 1.0)
rate (default 0.0)
axis (no default)
- 34 -
Celestia .CEL Scripting Guide
Orbit the currently selected object, using the currently defined Coordinate System, around the
specified axis. You must first use the select command to select an object, and optionally use the setframe command to define a Coordinate System, if one is not currently defined.
duration Number of seconds to orbit the object.
rate Speed at which to orbit the object, in units of degrees per second. Positive
and negative values are used to indicate the direction of orbit ("+" sign is
not necessary for positive values).
axis Define which axis to orbit around [X Y Z]. Set the X, Y, or Z value to 1 for
yes, 0 for no. You may also specify multiple axes. For example, to specify X
as the axis, use [1 0 0], for Y use [0 1 0], and for Z, use [0 0 1]. To
specify both, the X and Y axes, use [1 1 0].
Do not use a negative number for the duration argument, as the
command will be ignored.
The following example orbits Saturn for 12 seconds: select { object "Sol/Saturn" }
center { }
goto { time 3
distance 8
up [ 0 1 0 ]
upframe "equatorial" }
wait { duration 3 }
orbit { axis [ 0 1 0 ]
rate 30
duration 12 }
preloadtex
object (no default)
Pre-load the specified texture file from disk into memory.
object The name of the object who's texture is to be pre-loaded into graphics card
memory.
Depending on the file size of the texture being loaded, you may want to follow this command with
a wait command. If you are preloading multiple textures, or large textures, you should definitely
use a wait command. The wait duration will depend on the size of the texture file(s) and may
require some testing to get it just right.
This example pre-loads the texture file for Mars:
preloadtex { object "mars" }
- 35 -
Celestia .CEL Scripting Guide
print
text (no default)
origin (default "bottomleft")
duration (default 1.0)
row (default 0)
column (default 0)
The print command allows you to display text in Celestia's display window, defining where the text is positioned and for how long it should be displayed. You must follow the print command
with a wait command of a duration equal to or greater than the specified duration is required.
Beware: If the text you want printed is longer than the width of the user's window, it will run off the right edge of the window.
text The text you want displayed, surrounded by quote marks. You may also use
"\n" to generate a CR/LF at any position within the text string.
- 36 -
Celestia .CEL Scripting Guide
origin Starting position of the first character of your text. Must be one of the
following values:
* bottom
* bottomleft
* bottomright
* center
* left
* right
* top
* topleft
* topright
Description of the origins:
bottom: Bottom-center of the screen (not center justified).
bottomleft: Left edge, bottom of the screen.
bottomright: Right edge, bottom of the screen. You must use a negative column value, or your text will be outside the right edge of the window.
center: Center of the display screen (not center justified).
left: Left edge, half way down the screen.
right: Right edge, half way down the screen. You must use a negative column value, or your text will be outside the right edge of the window.
top: Top-center of the screen (not center justified).
topleft: Left side, top of the screen.
topright: Right edge, top of the screen. You must use a negative column value, or your text will be outside the right edge of the window.
Use row and column to adjust the origin vertical and horizontal
positions.
duration Number of seconds to display the text message.
row Defines the starting display line (vertical position), offset from the origin you specify, on which the text should be displayed. Positive values move
the starting row down, while negative values move the starting row up ("+" sign is not necessary for positive values).
For example, if you specify an origin of left, but you want it to start three
rows higher, then you would specify a row value of -3.
If you wanted the text to start three rows lower than the origin, you would specify a row value of 3.
- 37 -
Celestia .CEL Scripting Guide
column The column number (horizontal position) where the first character of the
text should be displayed. Column 0 (zero) is the left edge of the display
screen.
print command must be followed by a wait command with a The
duration equal to or greater than that of the print command. Otherwise, you will not see the text you printed to the screen.
duration argument, as the Do not use a negative number for the
command will be ignored.
This example prints the message "Hello Universe!" three rows up from the bottom of the display screen, starting two columns from the left edge:
print { text "Hello Universe!" row -3 column 2 }
wait { duration 1 }
This example prints the word "Hello" five rows up from the bottom of the display screen, starting
two columns from the left edge, and on the next line, prints the word "Universe!": print { text "Hello\nUniverse!"
origin "left"
duration 5
row -5
column 2 }
wait { duration 5 }
renderflags
set (no default)
clear (no default)
set (turn on) or clear (turn off) one or more of the items below to be displayed on the screen. The set and clear values can be any combination of the following values. Multiple values are specified within a single set of quotes (") by separating them with a vertical bar "|" (ie. "orbits|stars"). The items in the square brackets indicate the related keyboard command:
, atmospheres ...... Atmospheres [Ctrl+a]
, automag .......... Auto Magnitude [Ctrl+y]
, boundaries ....... Constellation boundaries [Ctrl+b]
, cloudmaps ........ Cloud textures [i]
, comettails ....... Comet tails [Ctrl+t]
, constellations ... Constellation labels [Ctrl+/]
, eclipseshadows ... Eclipse shadows [Ctrl+e]
, galaxies ......... Galaxy rendering [u]
, grid ............. Earth-based equatorial coordinate grid [;]
, markers .......... Markers [Ctrl+k]
, nightmaps ........ Night-side planet maps [Ctrl+l (L)]
- 38 -
Celestia .CEL Scripting Guide
, orbits ........... Object orbits [o]
, planets .......... Planet labels [p]
, pointstars ....... [no longer used -- see set command]
, ringshadows ...... Ring Shadows [no keyboard key]
, stars ............ Stars [none]
Examples:
renderflags { set "automag|atmospheres|nightmaps" } renderflags { clear "boundaries|galaxies|markers" } rotate
duration (default 1.0)
rate (default 0.0)
axis (no default)
Rotates the camera using the currently defined Coordinate System. You must first use the
select command to select an object, and optionally use the setframe command to set Coordinate System, if it is not currently defined.
duration The length of time, in seconds, to execute the rotate command.
rate Speed at which to rotate the camera. Positive and negative values are used
to indicate the direction of rotation ("+" sign is not necessary for positive
values).
axis Define which axis to rotate around [X Y Z]. Set the X, Y, or Z value to 1 for
yes, 0 for no. You may also specify multiple axes. For example, to specify X
as the axis, use [1 0 0], for Y use [0 1 0], and for Z, use [0 0 1]. To
specify both, the X and Y axes, use [1 1 0].
The rotate command must be followed by a wait command with a
duration equal to or greater than that of the rotate command.
Do not use a negative number for the duration argument, as the
command will be ignored.
The following example rotates the camera to the right (positive rate value) along the Z axis of the currently selected object for 5 seconds: rotate { duration 5
rate 10
axis [0 0 1] }
wait { duration 5 }
select
object (no default)
- 39 -
Celestia .CEL Scripting Guide
Selects the specified object in order to perform other commands on it. If you are currently positioned outside of our solar system, and want to select an object inside of our solar system, you
must include "Sol/" (our sun's name) in the object value, as shown in the example below.
object The name of a planet, moon, asteroid, comet, galaxy, spacecraft, etc.
If the object does not exist (ie. a misspelled name), the script will simply
continue to the next command without selecting any object at all, even if an object was previously selected.
Examples:
select { object "M33" } #(Galaxy M33)
select { object "Mars" } #(When in our Solar System)
select { object "Sol/Mars" } #(When outside of our Solar System) set
name (no default)
value or (default 0.0 or "")
Set one of the items listed below to the value specified in the value argument.
name Must be one of the following values:
* MinOrbitSize
* AmbientLightLevel
* FOV
* StarDistanceLimit
* StarStyle (How to display stars)
Descriptions for the above:
MinOrbitSize: This value is used when Celestia's render orbits option is
turned on. In general, when an object is very distant its orbit path will not be
shown. MinOrbitSize is the minimum radius (in pixels) which the orbit path
must cover before Celestia will draw it.
AmbientLightLevel: Brightness level of Ambient Light, 0.0 to 1.0 is the min
to max range. For realism, this should be set to 0.0. Setting it to 1.0 will cause
the side of a planet facing away from the sun to appear as bright as the lit side.
FOV: Field of View. Celestia computes this value relative to the size of the
display window, in pixels. The keyboard keys used to adjust FOV are the coma
and period ("," and ".").
StarDistanceLimit: The furthest distance at which Celestia will display
stars. The default value is 1,000,000, however, as of version 1.3.1, Celestia only
uses a distance out to 16,000 light years.
- 40 -
Celestia .CEL Scripting Guide
StarStyle: This allows you to set how Celestia displays stars on the screen.
The StarStyle value must be one of the following:
* fuzzypoints
* points
* scaleddiscs
value The value you want to assign to the name parameter.
Examples:
set { name "FOV" value 35.5 } set { name "StarStyle" value "points" } setfaintestautomag45deg
magnitude (default 8.5)
Set the lowest Magnitude of stars to be displayed when Auto-Magnitude is on.
magnitude The magnitude at which stars will become visible, when Auto-Magnitude
is on. The Celestia user interface allows a range from about 1.0 to 15.0.
Example:
setfaintestautomag45deg { magnitude 9.0 } setframe
ref (no default)
target (no default)
coordsys (default "universal")
Set the currently active Coordinate System (please refer to the Coordinate Systems section earlier
in this guide).
ref Defines the reference (first) object.
target Optional - Defines the target (second) object, for 2-object coordinate
systems, such as lock.
coordsys Must be one of the following values:
* chase
* ecliptical
* equatorial
* geographic
* lock
* observer
* universal
- 41 -
Celestia .CEL Scripting Guide
Only one Coordinate System can be active at any given time:
, chase (Chase)
, equatorial
, ecliptical (Follow)
, geographic (Sync Orbit)
, lock (Lock)
, observer
, universal (Free – ie. Esc key pressed)
The following example sets the Coordinate System to lock, which locks the Earth and Moon
together on the display:
setframe { ref "Sol/Earth"
target "Sol/Earth/Moon"
coordsys "lock" }
setorientation
angle (no default)
axis (no default)
-or-
ow (no default)
ox (no default)
oy (no default)
oz (no default)
Sets the camera orientation. If you are attempting to duplicate a position based on a Bookmark or
Cell://URL, you will also need to set the proper Coordinate System, position, and other
parameters. (Also see seturl.)
angle This value may be obtained from a Celestia Bookmark, which is stored in the
favorites.cel file located in the Celestia directory.
axis This value may be obtained from a Celestia Bookmark, which is stored in the
favorites.cel file located in the Celestia directory.
The ow, ox, oy and oz values represent the angle and axis as stored by a Cell://URL. They are
obtained from the following Cell://URL values:
&ow= &ox= &oy= and &oz=
Examples:
setorientation {
angle 0.945208
axis [ 0.81466 -0.570975 -0.101573 ] }
setorientation {
ow 0.090610
- 42 -
Celestia .CEL Scripting Guide
ox -0.494683
oy 0.860207
oz -0.084397 }
setposition
base (no default)
offset (no default)
-or-
x (no default)
y (no default)
z (no default)
Moves the camera to a specific position in the 3-dimensional universe. If you are attempting to
duplicate a position based on a Bookmark or Cell://URL, you will also need to set the proper
Coordinate System, orientation, and other parameters. (Also see seturl.)
base This value may be obtained from a Celestia Bookmark, which is stored in the
favorites.cel file located in the Celestia directory.
offset This value may be obtained from a Celestia Bookmark, which is stored in the
favorites.cel file located in the Celestia directory.
The x, y and z values represent the base and offset values as stored by a Cell://URL. They are obtained from the following Cell://URL values: ?x= &y= and &z=.
Both examples below position the camera to the same exact position in space outside of the Milky
Way:
setposition {
base [ -64132.43 47355.11 196091.57 ]
offset [ 0 0 -1.52e-005 ] }
setposition {
x "AMDCXoJK/3+IyGgR8f///w"
y "BvP2LRdAAAD/n5UGCw"
z "VUrGoeQJ+/8DyvenLQ" }
setsurface
name (no default)
Allows you to define an alternate surface texture for the currently selected object. An alternate
texture must first be defined in the solarsys.ssc file for the object in question.
For example, if you want to create an alternate surface texture for Earth, called "Earth-2", and it's
related texture filename is earth2.jpg, you would add the following entry to the solarsys.ssc file, after the closing brace for the ' "Earth" "Sol" ' entry:
AltSurface "Earth-2" "Sol/Earth"
- 43 -
Celestia .CEL Scripting Guide {
Texture "earth2.jpg"
}
In this example, "Earth-2" is the name of the alternate texture you will specify in the
setsurface command.
name Defines the name of the alternate texture defined in the AltSurface entry of the
solarsys.ssc file, not the name of the texture file itself.
Before using the setsurface command, you must first use the select
command to select an object.
To use the built-in Celestia "limit of knowledge" textures, instead of the interpretive ones, use:
setsurface { name "limit of knowledge" }
Example:
setsurface { name "Earth-2" }
setvisibilitylimit
magnitude (default 6.0)
Set the Magnitude of stars to be displayed, when Auto-Magnitude is off. The Celestia user interface allows a range from about 1.0 to 15.0.
magnitude Defines the magnitude at which stars will become visible, when
Auto-Magnitude is off.
Example:
setvisibilitylimit { magnitude 6.5 }
seturl
url (no default)
Move the camera to the location of a saved "location URL" (or Cell://URL), which you capture to
the clipboard using the Ctrl+C or Ctrl+Ins keys.
url Defines the Cell://URL to be used.
When you use the seturl command, all of the saved settings stored in the
Cell://URL are transferred to the user's currently running copy of Celestia.
Example:
seturl { url
- 44 -
Celestia .CEL Scripting Guide
"cel://Follow/Sol/2002-09-01T16:58:51.32378?x=AAAAAMCrktOdILb5/////w&y=CkxgAADEXts7E7HX/////w&z=VcpQAAAAAAAAAMIy/////w&ow=0.090610&ox=-0.494683&oy=0.860207&oz=-0.084397&select=Sol&fov=49.499992&ts=1.000000 (Julian Date, no default)
-or-
utc (Universal Time, no default)
Sets the Date and Time using a Julian Date (a decimal number) or a UTC time string, in the format YYYY-MM-DDTHH:MM:SS.SSSSS.
jd A valid Julian date.
utc A valid date in UTC format: YYYY-MM-DDTHH:MM:SS.SSSSS
To obtain a Julian Date from a normal calendar date, try the U.S. Navy Calendar Date/Time to Julian Date/Time converter, located at:
Examples of how to set the date and time to August 11, 2003 at 9:29:24 UTC: time { jd 2452862.89542 }
- 46 -
Celestia .CEL Scripting Guide
-or-
time { utc "2003-08-11T09:29:24.0000" }
timerate
rate (default 1.0)
Set the multiplier (speed) at which time changes.
rate Defines the time multiplier (ie. 100x).
Special values:
0 = Pause time
1 = Reset to Real Time
Negative values reverse time
This example sets the time multiplier to "1000x faster": timerate { rate 1000 }
track
(null)
Track the currently selected object, which keeps it centered in the display. The select command
must be used first, to select an object to be tracked.
For example, release your hold on any currently selected object (cancel), select the Earth (select), goto the Earth, and then track it. The Earth will begin to recede from you at the
speed it actually travels in space, but Celestia will track the Earth by keeping it centered in the display. The code example below demonstrates this, with time sped up by 1000x:
cancel { }
select { object "Sol/Earth" }
goto { time 3 distance 7 }
wait { duration 5 }
track { }
timerate { rate 1000 }
If you want the camera to remain at a constant distance from the object, add a follow command
after the track command.
If the currently selected object has track enabled, as of Celestia version 1.3.1 you can use the
following code to cancel a track command:
select { object "" }
track { }
The cancel command resets the Coordinate System to Universal. Thus, if you
want to use a different Coordinate System, you must use the setframe command
- 47 -
Celestia .CEL Scripting Guide
before using track.
unmark
object (no default)
If an object was previously marked, this command unmarks it.
object Defines the name of the object you want to unmark.
Example:
unmark { object "Sol/Earth" }
unmarkall
(null)
This command removes any previously assigned marks from all objects and disables the display
of marks.
Example:
unmarkall { }
wait
duration (default 1.0)
Pauses execution of the script for the specified duration value in seconds.
Do not use a negative number for the duration argument, as the command
will be ignored.
The following example pauses script execution for 15 ? seconds:
wait { duration 15.25 }
- 48 -
Celestia .CEL Scripting Guide
Deprecated CEL Scripting Commands
The commands listed in this section have been replaced with newer, more powerful or more general
commands. Though they continue to work for now, you should use the new command.
setambientlight
brightness (default 0.0)
Set the brightness level of Ambient Light.
This command was replaced with a value in the name parameter of the set command.
- 49 -
Celestia .CEL Scripting Guide
Document Version History
1.0f – Feb 2, 2004
* Added extra information to the move command and corrected the example.
* Added this section.
1.0g – June 17, 2004
* Corrected the object definition in the preloadtex command and corrected the example.
- 50 -
Celestia .CEL Scripting Guide
-------------------------
---< end of document >---
-------------------------
- 51 -
本文档为【for celestia, version 1.3.1 , created by chris laurel】，请使用软件OFFICE或WPS软件打开。作品中的文字与图均可以修改和编辑，
图片更改请在作品中右键图片并更换，文字修改请直接点击文字进行修改，也可以新增和删除文档中的内容。
该文档来自用户分享，如有侵权行为请发邮件ishare@vip.sina.com联系网站客服，我们会及时删除。
[版权声明] 本站所有资料为用户分享产生，若发现您的权利被侵害，请联系客服邮件isharekefu@iask.cn，我们尽快处理。
本作品所展示的图片、画像、字体、音乐的版权可能需版权方额外授权，请谨慎使用。
网站提供的党政主题相关内容(国旗、国徽、党徽..)目的在于配合国家政策宣传，仅限个人学习分享使用，禁止用于任何广告和商用目的。
浙公网安备 33021202002483