[SOLVED] Is it possible to create physics simulation (with Bullet Physics Engine and Panda3D) without the `render` object

Is it possible to create physics simulation (with Bullet Physics Engine and Panda3D) without the `render` object

Is it possible to create physics simulation without the render object?

I tried but it prints the identity matrices:

from panda3d.bullet import BulletWorld
from panda3d.core import Vec3
from panda3d.bullet import BulletBoxShape
from panda3d.bullet import BulletRigidBodyNode

world = BulletWorld()
world.setGravity(Vec3(0, 0, -9.81))

shape = BulletBoxShape(Vec3(0.5, 0.5, 0.5))
node = BulletRigidBodyNode('Box')
node.setMass(1.0)
node.addShape(shape)
world.attachRigidBody(node)

for i in range(10):
    world.doPhysics(0.016)
    print(node.getShapeTransform(0))

Solution

Solution:

from panda3d.bullet import BulletWorld
from panda3d.core import TransformState, Vec3, Quat, Point3
from panda3d.bullet import BulletBoxShape
from panda3d.bullet import BulletRigidBodyNode

world = BulletWorld()
world.setGravity(Vec3(0, 0, -9.81))

shape = BulletBoxShape(Vec3(0.5, 0.5, 0.5))
node = BulletRigidBodyNode('Box')
node.setMass(1.0)

p = Point3(1, 0, 0)
q = Quat.identQuat()
s = Vec3(2, 2, 2)

transform = TransformState.make_pos_quat_scale(p, q, s)
node.setTransform(transform)

node.addShape(shape)
world.attachRigidBody(node)

for i in range(10):
    world.doPhysics(0.016)
    print(node.getTransform())

Output:

T:(pos 1 0 0 scale 2)
T:(pos 1 0 -0.002507 scale 2)
T:(pos 1 0 -0.007521 scale 2)
T:(pos 1 0 -0.015042 scale 2)
T:(pos 1 0 -0.02507 scale 2)
T:(pos 1 0 -0.037605 scale 2)
T:(pos 1 0 -0.052647 scale 2)
T:(pos 1 0 -0.070196 scale 2)
T:(pos 1 0 -0.090252 scale 2)
T:(pos 1 0 -0.112815 scale 2)