Fix logging in SparseLDLSolver and update gravity in tutorial

- Disabled `printLog` in `SparseLDLSolver` within `header.py` for
cleaner output.
- Set `root_node.gravity` to `[0, -9.81, 0]` in `tuto_5.py` for
realistic gravitational effect.
- Added flexibility in constraint setup for `cable_node` by introducing
`is_constrained` parameter.
- Included missing `return root_node` statement to ensure complete scene
creation in `createScene()`.

examples/python3/useful/header.py

@@ -146,7 +146,7 @@ def addSolverNode(parent_node, name='solverNode', template='CompressedRowSparseM
     if iterative:
         solver_node.addObject('CGLinearSolver', name='Solver', template=template)
     else:
-        solver_node.addObject('SparseLDLSolver', name='Solver', template=template, printLog=True)
+        solver_node.addObject('SparseLDLSolver', name='Solver', template=template, printLog=False)
     if isConstrained:
         solver_node.addObject('GenericConstraintCorrection', linearSolver=solver_node.Solver.getLinkPath())
 

tutorial/tuto_scenes/tuto_5.py

@@ -34,7 +34,7 @@
 Params = Parameters(beam_geo_params=geoParams, beam_physics_params=physicsParams, simu_params=simuParams)
 
 femPos = [[0.0, 0, 0], [15., 0, 0], [30., 0, 0], [45., 0, 0], [60., 0, 0], [66., 0, 0], [81., 0.0, 0.0]]
-
+is_constrained = False
 
 class ForceController(Sofa.Core.Controller):
     def __init__(self, *args, **kwargs):
@@ -101,9 +101,9 @@ def onKeypressedEvent(self, event):
 
 def createScene(root_node):
     addHeader(root_node, is_constrained=True)
-    root_node.gravity = [0, 0., 0.]
+    root_node.gravity = [0, -9.81, 0.]
 
-    solver_node = addSolverNode(root_node, name="cable_node", isConstrained=True)
+    solver_node = addSolverNode(root_node, name="cable_node", isConstrained=is_constrained)
 
     # create cosserat Beam
     cosserat_beam = solver_node.addChild(CosseratBase(parent=solver_node, params=Params))
@@ -117,6 +117,8 @@ def createScene(root_node):
 
     finger_node, fem_points_node = addFEMObject(root_node, path=path, name="Finger")
 
+    return root_node
+
     #  This creates a new node in the scene. This node is appended to the finger's node.
     cable_state_node = cosserat_frames_node.addChild('cable_state_node')