DOOM Git Gud

If Nightmare mode is not enough of a challenge for you, you’d better just git gud:

DOOM Git Gud

Possibly the dumbest thing I’ve actually bothered to do based on a joke tweet:

This patch to Chocolate Doom challenges you to really stretch yourself by having the enemies actually shoot straight.

There’s not an easy way to make a new “GIT GUD” label, the graphics live in the WAD file which is separate and I can’t be bothered dealing with it. Just select the one which says “END GAME”.

Of course, DOOM GIT GUD expresses its distaste if you pick any other option:

I was originally intending to patch the enemies’ movement code to have them behave less stupidly than directly walking into fire, but it turns out that a one line patch to make them shoot straight is probably enough …

The change looks like a bit like this, in a few places:

-    angle += P_SubRandom() << 20;
+    angle += (gameskill < sk_gitgud) ? (P_SubRandom() << 20) : (P_SubRandom() << 16);

This code just takes angle, the correct angle for the enemy to be firing at to hit you, and modifies it a bit.

P_SubRandom() returns a random number between -255 and 255.

(Actually: the difference between two pseudo-random numbers between 0 and 255, so between -255 and 255 but with a bias towards the middle much like rolling two dice and adding them up)

angle is a 32 bit number representing 360⁰ of rotation, so P_SubRandom() << 20 represents an aiming error of about ±22⁰. P_SubRandom() << 16 is a much healthier aiming error of about ±1.4⁰, which seems like it’s roughly the same as what the player gets: if you’re shooting at a soldier, they hit you about as often as you hit them.

If that’s still too easy for you, change it to:

angle += (gameskill < sk_gitgud) ? (P_SubRandom() << 20) : 0;

And remember, “if you can win at all it’s because a person made it possible to win.”