Initial release (2 March 2016):
Kinematic: Updated locations and velocity every frame based on every GravityMass component in the scene. Can be run in realtime or with a specified step time. Physics substepping supported.
Kepler: Generates a mathematically precise orbit based on a single GravityMass. Can be run realtime or a specified step time.
Blended: Uses kinematic physics for an estimated position, then kepler physics for a precise distance for that location. Slightly more efficient than kepler mode.
-Draw a spline to show the orbit (requested by ruguevara)
-Calculate the future position of the orbit based on a specified time difference
-Calculate the future position of the orbit based on time since periapsis
-Orbit distance based on a specified true anomaly or eccentric anomaly
-Orbit position based on a specified true anomaly
-Get the true anomaly at a location
-Get eccentric anomaly at a location
-Get mean anomaly at a location
-Get a true anomaly from an eccentric anomaly
-Get an eccentric anomaly from a mean anomaly
-Velocity at a orbit location
-Velocity at an orbit true anomaly
-Get the orbit normal
-Get a vector that would generate a circular orbit
-Get a vector pointing to the orbit’s ascending node
Orbit data available
-Gravity direction and magnitude
-Relative orbit velocity
-Orbit type (Elliptical, hyperbolic, parabolic)
-Specific Orbit Energy
-Semi Major axis
-Semi Latus ******
-Time Since periapsis
-RAAN (longitude of ascending node)
-Longitude of descending node
-Argument of Periapsis
wow, great physic blueprints. May i confirm if this asset comes with all templates ?
Do you have documents with description/or use cases of the listed functions (have to confess it’s a bit hard for me to understand the list of functions & the “orbit data available” part)
Also, there’s the “rolling ball” example , I’m wondering if there is or if you have plan to implement a Cannonball Trajectory Arc/throw & bouncing ball - similar to angry birds.
If by templates you mean the “Rolling Template,” “First Person Shooter,” or “Flying” templates that the beginning of the videos start with, then Unreal Engine comes with those directly, not the plugin. You will then need to use those as starting points and follow the video tutorials, the blueprint does not come with the above tutorials already prebuilt.
For a better understanding of the orbital mechanics data, like true anomaly, eccentricity, etc. Wikipedia is probably your best bet for all that, it does a better job explaining those concepts then I could. I’ve also find this open source textbook helpful: https://books.google.com/books?id=O_7TCgAAQBAJ
Finally - you could technically use this blueprint for a cannonball trajectory/arc type functionality…but why would you? The unreal engine physics engine can do that more efficiently than a blueprint plugin. Unless you want gravity to vary as the cannonball gets further away from the ground…which is really just another way of describing an orbit
For the errors, it looks like you need to set the GravityMass ‘Owner’ property to the actor that you want the GravityMass to give gravity to. So, in your case, set the GravityMass owner to be your sun actor.If the Owner is blank it will throw out those errors. Ill add a check on startup to give a better formed error message.
I assume you are using the ‘Circular Orbit’ option, so if you want a planet in a circular orbit to orbit faster, you would need to give the sun more gravity. The “Standard Gravitational Parameter” option in the GravityMassActor defines the amount of gravitational force, so try increasing that. Also be sure to set the owner of the GravityMass actor to your sun.
For the 4.11 update, I will add a better error message for not having the GravityMass Owner defined, and add descriptions to the properties that are missing them.
To everyone, if you are looking into an orbiting physic blueprint. go get this one. For the money, you save your time/get the expert knowledge from Dingtech (yes, looks like he’s a physics expert) , not to mention the super support from him (I asked a few questions, he went ahead created a sample project for me lol)
Would this be capable of simulating a zero gravity experience? I see it can predict orbital patterns, but would it be capable of simulating something like a jetpack controlled space walk through ship debris? Where the ship debris is sort of just floating gently, and the astronaut must fly through to reach a finish.
Hello, yes, you could turn off gravity and use the plugin to have an actor simulate zero gravity. But it would also probably be fairly easy to do that without the plugin also :). The Flying Template that comes with the engine probably would get you 70-80% of the way there.
I am new at Unreal and I am tempted to get your plugin.
I would like to do a game based on a dynamic gravity system like the one you show in this video here, but I can’t find the github codes you mentionned at the beginning of the video.