// 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)
}
}
