// Handle movement assuming there is a physics body associated with the camera. // This attempts to smooth out movement by adding a higher initial velocity push // and then capping movement once max accelleration is reached. func (c *cam) move(bod vu.Pov, x, y, z float64, dir *lin.Q) { if body := bod.Body(); body != nil { boost := 40.0 // kick into high gear from stop. maxAccel := 10.0 // limit accelleration. sx, _, sz := body.Speed() if x != 0 { switch { case sx == 0.0: // apply push in the current direction. dx, dy, dz := lin.MultSQ(x*boost, 0, 0, dir) body.Push(dx, dy, dz) case math.Abs(sx) < maxAccel && math.Abs(sz) < maxAccel: dx, dy, dz := lin.MultSQ(x, 0, 0, dir) body.Push(dx, dy, dz) } } if z != 0 { switch { case sz == 0.0: dx, dy, dz := lin.MultSQ(0, 0, z*boost, dir) body.Push(dx, dy, dz) case math.Abs(sx) < maxAccel && math.Abs(sz) < maxAccel: dx, dy, dz := lin.MultSQ(0, 0, z, dir) body.Push(dx, dy, dz) } } } else { bod.Move(x, y, z, dir) } }