Wow, thank you.
You can clearly see that the guy’s arm is up, his elbow pointed towards the back like he’s holding a gun to someone and is getting ready to fire.
We know from earlier photos he was carrying an AK with a folding stock. It is obviously hard to tell from the grainy photo, but it looks like he is holding the rifle in front of him, not quite at 45 degrees. The driver is sitting low in comparison, but it still isn’t pointing at him yet. Totally justified shooting, but the evidence is ambiguous enough that there may be trouble for the shooter in liberal Travis county.