OpenRocket versions¶

orhelper supports OpenRocket 22.02, 23.09, 24.12 and 26.xx (the development version, for which there is no stable release yet). The integration tests, and every example, run against each of them. orhelper detects the Java package layout of the version it loads, so the same script works with all of them.

For 26.xx the tests were run on a snapshot build. For the other three, on the official releases.

What differs between versions¶

Most things are the same. These are the differences you may run into.

	22.02	23.09	24.12	26.xx
Members of `FlightDataType` you can request	56	56	60	73
Latitude and longitude in the results are in	radians	radians	degrees	degrees
`SIM_WARN` and `SIM_ABORT` events	no	no	yes	yes
Listener hooks `startSimulationBranch` and `endSimulationBranch`	no	no	no	yes
Java package of the classes	`net.sf.openrocket`	`net.sf.openrocket`	`info.openrocket.core`	`info.openrocket.core`
Java method of a flight branch that returns its name	`getBranchName()`	`getBranchName()`	`getName()`	`getName()`

Latitude and longitude change unit in 24.12

The same simulation, from a launch site at 45°N 10°E, gives 0.7854 and 0.1745 for TYPE_LATITUDE and TYPE_LONGITUDE in OpenRocket 22.02 and 23.09, and 45.0 and 10.0 in 24.12 and 26.xx. There is no error. If your script reads them, check the version, or convert with numpy.degrees.

Asking for a variable that your version doesn't have, for example TYPE_CNA (26.xx only), raises an AttributeError; the flight data reference shows where each is available. TYPE_PROPELLANT_MASS is a legacy name of TYPE_MOTOR_MASS, and both work with every version.

Picking a version¶

By default orhelper uses the installed OpenRocket. To use another one, pass its jar:

orhelper.OpenRocketInstance(jar="/path/to/OpenRocket-23.09.jar")

You can download every release from the OpenRocket releases page (OpenRocket-<version>.jar). A Python process can start only one JVM, so to compare versions, run each in its own process.

Java¶

OpenRocket 23.09 and newer need Java 17. 22.02 also runs on Java 11. The OpenRocket installers include a Java runtime that orhelper uses.