ggAstro Astronautics

ggame extensions for modeling spacecraft in planetary orbit

Planet

class ggame.astro.Planet(**kwargs)[source]

Initialize the Planet object.

Optional keyword parameters are supported:

Parameters:
  • viewscale (float) – Pixels per meter in graphics display. Default is 10.
  • radius (float) – Radius of the planet in meters. Default is Earth radius.
  • planetmass (float) – Mass of the planet in kg. Default is Earth mass.
  • color (int) – Color of the planet. Default is greenish (0x008040).
  • viewalt (float) – Altitude of initial viewpoint in meters. Default is rocket altitude.
  • viewanom (float) – True anomaly (angle) of initial viewpoint in radians. Default is the rocket anomaly.
  • viewanomd (float) – True anomaly (angle) of initial viewpoing in degrees. Default is the rocket anomaly.

Example:

"""
Example of using Planet class.
"""
from ggame.astro import Planet

EARTH = Planet(viewscale=0.00005)
EARTH.run()
run(userfunc=None)[source]

Execute the Planet (and Rocket) simulation without setting the initial view.

runWithRocket(rocket=None)[source]

Execute the Planet (and Rocket) simulation.

Optional parameters:
 
Parameters:rocket (Rocket) – Reference to a Rocket object - sets the initial view
Returns:None

Rocket

class ggame.astro.Rocket(planet, **kwargs)[source]

Rocket is a class for simulating the motion of a projectile through space, acted upon by arbitrary forces (thrust) and by gravitaitonal attraction to a single planetary object.

Required parameters:

Parameters:planet (Planet) – Reference to a Planet object.

Optional keyword parameters are supported:

Parameters:
  • bitmap (str) – Url of a suitable bitmap image for the rocket (png recommended), default is images/rocket.png
  • bitmapscale (float) – Scale factor for bitmap. Default is 0.1
  • velocity (float) – Initial rocket speed. Default is zero.
  • directiond (float) – Initial rocket direction in degrees. Default is zero.
  • direction (float) – Initial rocket direction in radians. Default is zero.
  • tanomalyd (float) – Initial rocket true anomaly in degrees. Default is 90.
  • tanomaly (float) – Initial rocket true anomaly in radians. Default is pi/2.
  • altitude (float) – Initial rocket altitude in meters. Default is zero.
  • showstatus (bool) – Boolean displays flight parameters on screen. Default is True.
  • int) statuspos ((int,) – Tuple with screen x,y coordinates of flight parameters. Default is upper left.
  • statuslist (list[str]) – List of status names to include in flight parameters. Default is all, consisting of: “velocity”, “acceleration”, “course”, “altitude”, “thrust”, “mass”, “trueanomaly”, “scale”, “timezoom”, “shiptime”
  • leftkey (str) – A ggame.event.KeyEvent key identifier that will serve as the “rotate left” key while controlling the ship. Default is ‘left arrow’.
  • rightkey (str) – A ggame.event.KeyEvent key identifier that will serve as the “rotate right” key while controlling the ship. Default is ‘right arrow’.

Following parameters may be set as a constant value, or pass in the name of a function that will return the value dynamically or the name of a ggmath UI control that will return the value.

Parameters:
  • or float timezoom (function) – Scale factor for time zoom. Factor = 10^timezoom
  • or float heading (function) – Direction to point the rocket in (must be radians)
  • or float mass (fucntion) – Mass of the rocket (must be kg)
  • or float thrust (function) – Thrust of the rocket (must be N)

Animation related parameters may be ignored if no sprite animation:

Parameters:
  • bitmapframe (Frame) – ((x1,y1),(x2,y2)) tuple defines a region in the bitmap
  • bitmapqty (int) – Number of bitmaps – used for animation effects
  • bitmapdir (str) – “horizontal” or “vertical” use with animation effects. Default is “horizontal”
  • bitmapmargin (int) – Pixels between successive animation frames
  • tickrate (float) – Frequency of spacecraft dynamics calculations (Hz)

Example:

"""
Example of using Rocket class.
"""
from ggame.astro import Planet, Rocket

EARTH = Planet(viewscale=0.00005)
EARTH.run()

ROCKET = Rocket(EARTH, altitude=400000, velocity=7670, timezoom=2)
planet = None

Reference to an app object of Planet class

tickrate = None

Target animation frames per second.

localheading = None

Heading (angle) of travel

timezoom = None

Reference to a function that will dynamically determine the time zoom factor. An integer: 1,2,3 faster, -1, slower.

heading = None

Reference to a function that will dynamically calculate spaceship orientation or heading (in radians)

mass = None

Reference to a function that will dynamically calculate the spaceship mass (in kg).

thrust = None

Reference to a funtion that will dynamically calculate the rocket thrust (in N).

addStatusReport(statuslist, statusfuncs, statusselect)[source]

Accept list of all status names, all status text functions, and the list of status names that have been selected for display.

Parameters:
  • statuslist (list[str]) – List of status names to include in flight parameters. Default is all, consisting of: “velocity”, “acceleration”, “course”, “altitude”, “thrust”, “mass”, “trueanomaly”, “scale”, “timezoom”, and “shiptime”.
  • statusfuncs (list[func]) – List of function references corresponding to statuslist parameter.
  • statusselect (list[str]) – List of names chosen from statuslist to display.
Returns:

None
xyposition

Report the x,y tuple for logical position of the spaceship.

tanomalyd

Report/set the spaceship position as a direction relative to central body (degrees).

altitude

Report/set the spaceship altitude of planet surface in meters.

velocity

Report the spaceship velocity scalar in m/s.

acceleration

Report the spaceship acceleration scalar in m/s.

tanomaly

Report/set the spaceship position as a direction relative to central body (radians).

r

Report the spaceship distance (radius) from central body center of mass.