plugin and OrbitView ?

[vfabien21]

Hello, I wonder if it is possible to alter the behaviour of a ressouce thanks to a plugin ?
For example, I'd like to OrbitView to record points on a fix time rate instead of every n calculated points (mix of selection / interpolation between calculated points). Would such a thing be possible, or do I need to dive into the source code ?

Regards

[jjkparker]

Hi, thanks for the question. This mode of operation isn't supported in the current OrbitView resource, so it would require some kind of software development to make it work. We don't support plugins to existing GUI resources right now, so I think the only course of action here would be to implement the change directly in the existing OrbitView. Or create a new type of OrbitView based on the original. But yes, both of these would require getting into the source code.

Joel

[vfabien21]

Hello Joel,

Thank you for your reply. Ok, so the way to go would be to develop a new OrbitView. Hmm, I'll have a look at that, but it'll depend on the ressource I have...
I see some features which could be interesting :
- Time based animation
- Icon and text inclusion along the trajectory (for example periapsis/apoapsis localisation, spacecraft, burns,...). Maybe controlled with a plugin/ressource
- Color of each trajectory point (for example ranging from red to blue, where red is the minimum speed in the simulation, and bleu the max). Maybe controlled with a plugin/ressource.
EDIT :
- Correct me if I am wrong, but OrbitView can follow a craft or a planet moving in the referential. It might be another nice addition.

Well, if I was to focus on the animation speed only, an easier solution might be to modify a propagator in such a way that the output is a fixed time step (even in the box the propagator uses the usual variable time step).

[jjkparker]

Yes, we're working on labeling and different trajectory colors in OrbitView now. Those should be in our next release.

If you want time-based animation right now, you could do what you suggest and propagate at fixed steps. The recommended way of doing this is:

Code: Select all

Create ForceModel DefaultProp_ForceModel
DefaultProp_ForceModel.ErrorControl = None    % set this to 'None'

Create Propagator DefaultProp
DefaultProp.FM = DefaultProp_ForceModel
DefaultProp.InitialStepSize = 60    % set this to the fixed time step you want


[vfabien21]

Thank you joel,

Ok, so I won't touch colors yet.
Yes, that solution would work, but also waste the benefit of variable step size of propagators. Calculation and display are 2 different things...

[jjkparker]

I created a feature request for the fixed-step animation. Feel free to provide more details on the ticket.

http://li64-187.members.linode.com:8080/browse/GMT-4223

[vfabien21]

Okay, thank you. But apparently it is more complicated than I thought...

[JohnMarshall]

If you go with traditional style of altering the behavior of plug-in it will not work. But, if you can follow the tutorial article which is published in thesis review service blog and implement those steps which are said in that tutorial you can easily change the mode of operation of orbit view.