Real-time 3D visualization of space
https://celestiaproject.space/forum/
https://celestiaproject.space/forum/viewtopic.php?f=25&t=15955
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-- ORBITAL PERIODS OF SOLAR SYSTEM PLANETS
--
-- a CELX script
--
-- by: Gary M. Winter. © 2010. All rights reserved.
--
-- for use with the incredible, free astronomy-simulation software
-- CELESTIA (www.shatters.net/celestia)
--
-- CELESTIA is by:
-- Chris Laurel, , Clint Weisbrod, Fridger Schrempp,
-- Christophe Teyssier, Grant Hutchison, Pat Suwalski,
-- Toti, Da Woon Jung, Hank Ramsey, Bob Ippolito,
-- Vincent Giangiulio and Andrew Tribick.
-- versions 1.4.1 and before: © 2001-2006 Chris Laurel
-- later versions: © 2001-2009 Celestia Development Team
--
--
-- This script gives your distance from the Sun and tells you
-- the Period of any planet whose orbital semi-major axis equals
-- that distance. Remember: as long as planets' masses are small
-- compared to that of their parent star, in a given star system two
-- planets with equal semi-major axes will have the same period;
-- it doesn't matter how eccentric their orbits may be. Therefore,
-- a planet in a highly elongated orbit with a semi-major axis of
-- 2 AU will have the same period as one with a circular orbit with
-- a radius of 2AU. A circular orbit is simply a special case where
-- the orbit's semi-major and semi-minor axes are the same.
--
-- Note for CELX programmers:
-- I started to extend this script to give orbital periods of all planets,
-- stars, moons etc. in Celestia but unfortunately found the following:
-- 1) Celestia's getinfo( ) method does not return a .mass key for stars;
-- 2) worse, even for planets and moons, getinfo( ) always returned zero
-- in its .mass key.
--
-- Code used for above:
-- Selection = celestia : getselection ( )
-- SelectionTable = Selection : getinfo ( )
-- SelectionMass = SelectionTable.mass
--
-- ---------------------------------------------------------
-- BACKGROUND
--
-- 1 AU = 149597869.4 km
-- mu = G ( m1 + m2 ) rigorously, the Gravitational Parameter
-- but m2 (the mass of planet, satellite, etc.) is usually very small compared to m1 (the mass of parent star, planet etc.)
-- so mu = G*m1 is substituted
-- ---------------------------------------------------------
-- CONSTANTS
PI = 3.14159265359
-- ---------------------------------------------------------
-- FUNCTIONS
function celestia_cleanup_callback()
-- empty function
end
function ShowObjectPeriod( )
SunPosition = Bodies[1] : getposition ( celestia:gettime( ) )
ViewerPosition = celestia : getobserver ( ) : getposition ( )
SemiMajorAxisInAU = SunPosition:distanceto ( ViewerPosition ) / 149597869.4
Period = math.sqrt( SemiMajorAxisInAU ^ 3 )
DistanceString = string.format(" Your distance from the Sun is: %5.6f AU.\n A solar planet in an orbit with a \"semi-major axis\"\n this large has a period of: %5.6f Years.\n Press the X key to eXit.", SemiMajorAxisInAU, Period )
celestia:print(DistanceString)
end -- of ShowObjectPeriod( )
function celestia_keyboard_callback(KeyPress)
local TrapKey = false
if KeyPress == "X" or KeyPress == "x" then
TrapKey = true
Exit = true
end
return TrapKey
end
-- ---------------------------------------------------------
-- START PROGRAM
Bodies = { }
Bodies[1] = celestia:find("Sol")
Exit = false
celestia:print(" ORBITAL PERIODS OF SOLAR SYSTEM PLANETS\n © 2010 Gary M. Winter\n All rights reserved.", 100 )
for i=1, 4 do
wait(0.7)
end
celestia:requestkeyboard(true)
repeat
wait(0)
ShowObjectPeriod( )
until Exit
celestia:print("\n\n Exiting \"ORBITAL PERIODS OF SOLAR SYSTEM PLANETS\" . . . May your journeys be joyous!", 3)
-- WE'RE DONEduds26 wrote:OMG!! VB!?! COme on!!
Please use some decent language: C/C++. Of if you prefer scripting: Python, Lua.
And please use some decent toolkit: Qt addon for Visual Studio.
That's what WE use at Celestia for ALL our extensive data related tasks (for good reasons). Perl is certainly a most powerful and modern (obejct oriented) cross-platform scripting language. ajtribick wrote:Hang on a minute here let's not bash the beginning-level programmer over their choice of programming language. And let's bear in mind that VB.Net and VBA are very different beasts. Yes the vendor-specific nature of the .Net environment is not ideal (to put it politely), but the .Net environment is actually quite a nice one to work with.
Apparently "bash Microsoft and all who dare associate with it" trumps encouraging new programmers round here. I think that's a bit of a shame really.
t00fri wrote:ajtribick wrote:Hang on a minute here let's not bash the beginning-level programmer over their choice of programming language. And let's bear in mind that VB.Net and VBA are very different beasts. Yes the vendor-specific nature of the .Net environment is not ideal (to put it politely), but the .Net environment is actually quite a nice one to work with.
Apparently "bash Microsoft and all who dare associate with it" trumps encouraging new programmers round here. I think that's a bit of a shame really.
I agree as to bashing beginning programmers. Yet, as I suggested above, a few lines of Lua for that trivial 3rd Kepler law formula does not seem requesting too much ... Notably since Lua is already there in every copy of Celestia
As to VB.Net etc, I can't see much of a justification for coding tools in such a language., given that they should be supporting cross-platform Celestia! As far as I know, VB.net only works for Windows, right?
Incidentally, there is a large amount of competent "anti-writing" against Microsoft's Net philosophy/environment. The latter doesn't seem to be REALLY "catching on" (despite massive PR-pressure from MS)
Fridger
Also, here's the VB version:Because I'm familiar with them. You got a problem with that?t00fri wrote:What's the purpose of using such antiquated MS-specific code like VisualBasic and Exel??
I thought you wanted to learn a little bit about coding with this simple project? Sorry...W0RLDBUILDER wrote:The spreadsheet CAN be opened on OpenOffice.org Calc.
http://tbh-1138.deviantart.com/art/Orbi ... -166958665Because I'm familiar with them.t00fri wrote:What's the purpose of using such antiquated MS-specific code like VisualBasic and Exel??
You got a problem with that?
. You will make your friends at Deviantart happy with it.
Finally, why didn't you include Perl on the scripting side?
+++++++++++++
Besides your overflowing wise remarks, we would be glad seeing also some neat graphical code from YOU at times, ...
+++++++++++++
F.
I AM SERIOUS, you gotta love CODE SNIPPETS+TEMPLATES used right!Actually you can't be serious to even request Qt widgets for calculating a trivial one-line formula...
As I wrote above, a tiny lua script (coded and tested in 5 minutes) is just adequate for such a simple task.