Bouncing Ball. Making it slow down at peak of height

Use ‘real’ physics for that.

  1. ball have parameters

    • acceleration a(ax,ay,az) [m/s^2]… this is sum of all forces driving ball divided by its mass
    • velocity v(vx,vy,vz) [m/s]… actual speed = integration of acceleration v += a * dt
    • position p(x,y,z) [m]… actual position = integration of velocity p += v * dt
    • radius r [m]
    • mass m [kg]
    • dt [s] … iteration step (update time)

    init start a,v values to (0,0,0) and p to start position

  2. apply gravity, friction, collision

    • gravity for example g(gx=0,gy=-9.81,gz=0)
    • friction f2 = -(|v|^2)*c2 * (v/|v|) … in gas
    • friction f3 = -(|v|^3)*c3 * (v/|v|) … in liquid

    if position before and after cross collision border reflect velocity * collision coef <=1 by impact normal also you can reflect position if crossing border is not possible.

  3. put it all together in some timer / updating code with dt interval

    a =g+(f2+f3+(driving force))/m
    v+=a*dt
    p+=v*dt
    test_collisions()
    redraw()
    
  4. for manual change of position

    just set p(x,y,z) to new position and also can set v=(0,0,0) to stop the ball

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