#you can set the restitution (bouncyness) of an object in the URDF file
#or using changeDynamics

import pybullet as p
import time

cid = p.connect(p.SHARED_MEMORY)
if (cid < 0):
  cid = p.connect(p.GUI)
restitutionId = p.addUserDebugParameter("restitution", 0, 1, 1)
restitutionVelocityThresholdId = p.addUserDebugParameter("res. vel. threshold", 0, 3, 0.2)

lateralFrictionId = p.addUserDebugParameter("lateral friction", 0, 1, 0.5)
spinningFrictionId = p.addUserDebugParameter("spinning friction", 0, 1, 0.03)
rollingFrictionId = p.addUserDebugParameter("rolling friction", 0, 1, 0.03)

plane = p.loadURDF("plane_with_restitution.urdf")
sphere = p.loadURDF("sphere_with_restitution.urdf", [0, 0, 2])

p.setRealTimeSimulation(1)
p.setGravity(0, 0, -10)
while (1):
  restitution = p.readUserDebugParameter(restitutionId)
  restitutionVelocityThreshold = p.readUserDebugParameter(restitutionVelocityThresholdId)
  p.setPhysicsEngineParameter(restitutionVelocityThreshold=restitutionVelocityThreshold)

  lateralFriction = p.readUserDebugParameter(lateralFrictionId)
  spinningFriction = p.readUserDebugParameter(spinningFrictionId)
  rollingFriction = p.readUserDebugParameter(rollingFrictionId)
  p.changeDynamics(plane, -1, lateralFriction=1)
  p.changeDynamics(sphere, -1, lateralFriction=lateralFriction)
  p.changeDynamics(sphere, -1, spinningFriction=spinningFriction)
  p.changeDynamics(sphere, -1, rollingFriction=rollingFriction)

  p.changeDynamics(plane, -1, restitution=restitution)
  p.changeDynamics(sphere, -1, restitution=restitution)
  pos, orn = p.getBasePositionAndOrientation(sphere)
  #print("pos=")
  #print(pos)
  time.sleep(0.01)