Unable to see two .stl at the same time

[rickysaettone]

The issue:

I can't visualize two of the .stl objects at the same time but I can see them separately.
Not only does the plane disappear while trying to show both, but also the position of the actuator seems transformed and a two vertices appear in a weird position too.
Can anyone help me please? I am starting to learn SOFA and python in general.

Location of the objects: STL.zip

• actuator located in STL/actuador.stl
• plane located in STL/plane.stl

Version:

• OS: Windows 11 version: 10.0.22631
• SOFA v23.06.00 via the installer
• Python 3.8.10

The code:

#-*- coding: utf-8 -*-
import Sofa
#import contoller.py

def createScene(rootNode):
    
    # Required plugins
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.IO.Mesh') # Needed to use components [MeshSTLLoader]
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.Mapping.Linear') # Needed to use components [IdentityMapping]
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.Mass') # Needed to use components [UniformMass]
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.StateContainer') # Needed to use components [MechanicalObject]
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.Visual') # Needed to use components [VisualStyle]
    rootNode.addObject('RequiredPlugin', name='Sofa.GL.Component.Rendering3D') # Needed to use components [OglModel]
    rootNode.addObject('VisualStyle', displayFlags='showForceFields showBehaviorModels')
    
    rootNode.addObject('DefaultAnimationLoop')
    rootNode.addObject('DefaultVisualManagerLoop')

    # Setting the timestep in seconds
    rootNode.dt = 0.01
    rootNode.addObject('RequiredPlugin',
                       pluginName='SoftRobots SofaPython3')
    
    # Load the mesh file of the actuator and the plane.
    rootNode.addObject('MeshSTLLoader', name='loader_actuator', filename='STL/Actuador.stl')
    rootNode.addObject('MeshSTLLoader', name='loader_plane', filename='STL/plane.stl')

    # Basic mechanical modelling of the actuator
    actuator = rootNode.addChild('MechanicalModel')
    actuator.addObject('MechanicalObject', name='actuator',
                       translation=[0,0,0],
                       showObject=True, showObjectScale=1.0,
                       rotation=[0.0, 0.0, 0.0])
    actuator.addObject('UniformMass')

    # Visual object for actuator
    visual_actuator = rootNode.addChild('VisualModelActuator')
    visual_actuator.addObject('OglModel', name='renderer_actuator',
                              src=rootNode.loader_actuator.getLinkPath(),
                              color=[1.0, 1.0, 1.0, 0.5])
    visual_actuator.addObject('IdentityMapping',
                              input=actuator.actuator.getLinkPath(),
                              output=visual_actuator.renderer_actuator.getLinkPath())
    
    
    
    # Basic mechanical modelling of the plane
    plane = rootNode.addChild('MechanicalModelPlane')
    plane.addObject('MechanicalObject', name='plane',
                    position=rootNode.loader_plane.position.getLinkPath(),
                    showObject=True, showObjectScale=1.0,
                    rotation=[0.0, 0.0, 0.0])
    plane.addObject('UniformMass')

    # Visual object for plane
    visual_plane = rootNode.addChild('VisualModelPlane')
    visual_plane.addObject('OglModel', name='renderer_plane',
                           src=rootNode.loader_plane.getLinkPath(),
                           color=[0.5, 0.5, 0.5, 1.0])
    visual_plane.addObject('IdentityMapping',
                           input=plane.plane.getLinkPath(),
                           output=visual_plane.renderer_plane.getLinkPath())
    
    
    '''
    def onAnimateBeginEvent(event):
    rootNode = event['rootNode']
    pressureComponent = rootNode.getObject('pressureComponent')
    if pressureComponent:
        pressure = pressureComponent.findData('pressure').value
        print(f'Pressure: {pressure}')
    
    '''
    return rootNode

def main():
    import Sofa.Gui
 
    root=Sofa.Core.Node("root")
    createScene(root)
    Sofa.Simulation.init(root)
 
    Sofa.Gui.GUIManager.Init("myscene", "qglviewer")
    Sofa.Gui.GUIManager.createGUI(root, __file__)
    Sofa.Gui.GUIManager.SetDimension(1080, 1080)
    Sofa.Gui.GUIManager.MainLoop(root)
    Sofa.Gui.GUIManager.closeGUI()
 
    print("End of simulation.")
 
 
if __name__ == '__main__':
    main()

[hugtalbot]

Thanks for rising the point @rickysaettone
I will create an issue from your discussion, this seems to be a real problem. Thanks for reporting 👍

[epernod]

Hi,

I just checked on my side. The problem is not coming from the MeshSTLLoader but how you structured your scene file.

The first mechanical Object is missing position=rootNode.loader_actuator.position.getLinkPath(),
Then I also suggest that the mapped node should be child of the first node with the mechanicalObject to avoid any confusion in the identityMapping: visual_actuator = actuator.addChild('VisualModelActuator')

Here is a working version with other mesh available in the SOFA source code base.

#-*- coding: utf-8 -*-
import Sofa
#import contoller.py

def createScene(rootNode):
    
    # Required plugins
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.IO.Mesh') # Needed to use components [MeshSTLLoader]
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.Mapping.Linear') # Needed to use components [IdentityMapping]
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.Mass') # Needed to use components [UniformMass]
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.StateContainer') # Needed to use components [MechanicalObject]
    rootNode.addObject('RequiredPlugin', name='Sofa.Component.Visual') # Needed to use components [VisualStyle]
    rootNode.addObject('RequiredPlugin', name='Sofa.GL.Component.Rendering3D') # Needed to use components [OglModel]
    rootNode.addObject('VisualStyle', displayFlags='showForceFields showBehaviorModels')
    
    rootNode.addObject('DefaultAnimationLoop')
    rootNode.addObject('DefaultVisualManagerLoop')

    # Setting the timestep in seconds
    rootNode.dt = 0.01
    rootNode.addObject('RequiredPlugin',
                       pluginName='SofaPython3')
    
    # Load the mesh file of the actuator and the plane.
    rootNode.addObject('MeshSTLLoader', name='loader_actuator', filename='mesh/circle_knot_ascii.stl')
    rootNode.addObject('MeshSTLLoader', name='loader_plane', filename='mesh/dragon.stl')

    # Basic mechanical modelling of the actuator
    actuator = rootNode.addChild('MechanicalModel')
    actuator.addObject('MechanicalObject', name='actuator',
                       position=rootNode.loader_actuator.position.getLinkPath(),
                       translation=[0,0,0],
                       showObject=True, showObjectScale=1.0,
                       rotation=[0.0, 0.0, 0.0])
    actuator.addObject('UniformMass')

    # Visual object for actuator
    visual_actuator = actuator.addChild('VisualModelActuator')
    visual_actuator.addObject('OglModel', name='renderer_actuator',
                              src=rootNode.loader_actuator.getLinkPath(),
                              color=[1.0, 1.0, 1.0, 0.5])
    visual_actuator.addObject('IdentityMapping',
                              input=actuator.actuator.getLinkPath(),
                              output=visual_actuator.renderer_actuator.getLinkPath())
    
    
    
    # Basic mechanical modelling of the plane
    plane = rootNode.addChild('MechanicalModelPlane')
    plane.addObject('MechanicalObject', name='plane',
                    position=rootNode.loader_plane.position.getLinkPath(),
                    showObject=True, showObjectScale=1.0,
                    rotation=[0.0, 0.0, 0.0])
    plane.addObject('UniformMass')

    # Visual object for plane
    visual_plane = plane.addChild('VisualModelPlane')
    visual_plane.addObject('OglModel', name='renderer_plane',
                           src=rootNode.loader_plane.getLinkPath(),
                           color=[0.5, 0.5, 0.5, 1.0])
    visual_plane.addObject('IdentityMapping',
                           input=plane.plane.getLinkPath(),
                           output=visual_plane.renderer_plane.getLinkPath())
    
    
    '''
    def onAnimateBeginEvent(event):
    rootNode = event['rootNode']
    pressureComponent = rootNode.getObject('pressureComponent')
    if pressureComponent:
        pressure = pressureComponent.findData('pressure').value
        print(f'Pressure: {pressure}')
    
    '''
    return rootNode

def main():
    import Sofa.Gui
 
    root=Sofa.Core.Node("root")
    createScene(root)
    Sofa.Simulation.init(root)
 
    Sofa.Gui.GUIManager.Init("myscene", "qglviewer")
    Sofa.Gui.GUIManager.createGUI(root, __file__)
    Sofa.Gui.GUIManager.SetDimension(1080, 1080)
    Sofa.Gui.GUIManager.MainLoop(root)
    Sofa.Gui.GUIManager.closeGUI()
 
    print("End of simulation.")
 
 
if __name__ == '__main__':
    main()

[rickysaettone]

Thank you very much! There was also a problem with the origin of the Actuador.stl, it was far away from its body and the dimensions were also too big.