Show all scene child nodes

[imnegan]

Hi all,

I am building a model of the solar system using the Scene class. In the model each planet is a child node of the sun, and the moons are child nodes of their respective planets.

Is there a way to show all child nodes of a selected node on screen without adding them as child node of the Scene itself? For example: Jupiter, when selected, is at the centre of the screen as the parent node. All of its moons (Io, Europa, etc) are Jupiter's child nodes and would be shown also.

[ccc]

It is hard to answer these questions without working code. My sense is that a sprite's children need to be inside its frame while the planets orbit around the outside of the sun's frame. I am no good with scene animations but we need some sample code of a rotating planet in an elliptical orbit around a star... (help needed!)

import scene

'''
Trying to create a rotating earth in an eliptical orbit around the sun.
'''

class SolorSystemScene(scene.Scene):
   def setup(self):
       center = self.bounds.center()
       sun = scene.SpriteNode('plc:Star', position=center, parent=self)
       earth = scene.SpriteNode('plc:Tree_Ugly', position=center + (150, 150),
                                parent=self, speed=0.2)
       earth.run_action(scene.Action.rotate_by(10))
       earth.run_action(scene.Action.move_to(center.x - 150, center.y - 150))

scene.run(SolorSystemScene())

[abcabc]

Hope this helps

import scene
from math import pi

'''
Trying to create a rotating earth in an eliptical orbit around the sun.
'''

class SolorSystemScene(scene.Scene):
    def setup(self):
        center = self.bounds.center()
        sun = scene.SpriteNode('plc:Star', position=center, parent=self)
        earth_anchor = scene.Node(position=center, parent=self)
        earth = scene.SpriteNode('plc:Tree_Ugly', position=(0, 150))
        earth_anchor.add_child(earth) 
        self_rotate_action = scene.Action.repeat(scene.Action.sequence(scene.Action.rotate_to(20*pi, 5),
            scene.Action.rotate_to(0,0), 0),0)      
        earth.run_action(self_rotate_action)
        rotate_action = scene.Action.repeat(scene.Action.sequence(scene.Action.rotate_to(20*pi, 20),
            scene.Action.rotate_to(0,0), 0),0)
        earth_anchor.run_action(rotate_action)

scene.run(SolorSystemScene())

[ccc]

Cool... more appropriate icons, clockwise rotation, etc...

Edit: counter clockwise rotation and orbit in alignment with @JonB comments below...

import scene
from math import pi

'''
Trying to create a rotating earth in an eliptical orbit around the sun.
'''


class SolorSystemScene(scene.Scene):
    def setup(self):
        center = self.bounds.center()
        sun = scene.SpriteNode('emj:Sun_1', position=center, parent=self)
        earth_anchor = scene.Node(position=center, parent=self)
        earth = scene.SpriteNode('emj:Moon_5', position=(0, 150))
        earth_anchor.add_child(earth)
        A = scene.Action
        self_rotate_action = A.repeat(A.sequence(A.rotate_to(20 * pi, 5),
                                                 A.rotate_to(0, 0), 0), 0)
        earth.run_action(self_rotate_action)
        rotate_action = A.repeat(A.sequence(A.rotate_to(20 * pi, 20),
                                            A.rotate_to(0, 0), 0), 0)
        earth_anchor.run_action(rotate_action)

scene.run(SolorSystemScene())

[JonB]

In this solar system, all the planets orbit counterclockwise, and most rotate that way too...

[ccc]

Thanks @JonB I corrected inline above... Now all is right with the universe ;-). Happy 2017!

[ccc]

More Planets...

import scene
from math import pi

A = scene.Action

'''
Trying to create a rotating earth in an eliptical orbit around the sun.
'''

def make_action(steps, speed):
    return A.repeat(A.sequence(A.rotate_to(steps * pi, speed),
                               A.rotate_to(0, 0), 0), 0)


class Planet(scene.Node):
    def __init__(self, parent, orbit=150, image_name=''):
        parent.add_child(self)
        self.position = parent.bounds.center()
        self.run_action(make_action(20, orbit / 5))
        image_name = image_name or 'emj:Moon_5'        
        planet = scene.SpriteNode(image_name, parent=self, position=(0, orbit))
        planet.run_action(make_action(20, 5))
        
        
class SolorSystemScene(scene.Scene):
    def setup(self):
        center = self.bounds.center()
        sun = scene.SpriteNode('emj:Sun_1', position=center, parent=self)
        earth = Planet(self)
        venus = Planet(self, 75, 'emj:Blue_Circle')
        mars = Planet(self, 225, 'emj:Moon_2')
        saturn = Planet(self, 300, 'emj:Moon_4')
        jupiter = Planet(self, 375, 'emj:Moon_1')

scene.run(SolorSystemScene())