Usually something sudden indicates loss of spark. Check the wires. See if you have spark to the plugs. Go from there.
Oh, yeah,i should have mentioned that. Benny told me the same thing and I actually checked the shaft before he even said anything. When i first saw the shattered rotor,i wondered what the hell could have causedCheck for play in the rotor shaft inside the distributor. If the shaft is able to move off its center it can allow the rotor to impact the inside of the cap and can pretty much look like your pictures.