Why do monsters hit you so easily/quickly when you land on top of them?

Expecting a simple answer, but I have noticed that (particularly with demons/spectres) if I land on top of them I get hit instantly, almost every time.

It may be the source port your using. In vanilla you can't actually stand "on top" of them but rather fall down. What source port do you use? It might be it's codding probably.

Sorry, gzdoom

Yes, it's probably the codding. I'm not entirely sure what causes it beyond that however.

The way melee attacks work with monsters is you will always take damage if you're touching their bounding box at the time they slash or bite, so if you you're standing on top of them, you're probably touching them, which makes you take damage from the bite. Depending on whether the source port your using "fixes" it, you can actually stand at the edge of a really tall ledge, with spectres or demons on the bottom, they can bite from down below just by lining up the edges of your bounding box, even from a 1000 foot height difference. Its unfair sometimes but Doom wasn't designed to consider vertical combat, involving mouse looking or standing on top of things.

Perfect, just the answer I was looking for!

Thanks guys.

40oz said:

Its unfair sometimes but Doom wasn't designed to consider vertical combat, involving mouse looking or standing on top of things.

Call it engine limitations since it wasn't really designed to determine 3D collisions, at least not with actors. Though it probably wasn't in their best interest to showcase the flaw in one of the Ultimate Doom demos. XD

Hahah yeah that MAP05 demo really irks me. He would have lived a lot longer if he didn't take that 30+ damage from those imps at the bottom of the window :P

40oz said:

Hahah yeah that MAP05 demo really irks me. He would have lived a lot longer if he didn't take that 30+ damage from those imps at the bottom of the window :P

Yeah, it also had a stupidly easy death even considering the fact that 1. he picked up a FUCKING SOULSPHERE 2. demos are by definition designed to die in them (except for the first one of Shareware Doom, though the dude still barely escapes E1M2 due to a probably forced stupidity). So much for this little "thread derail".

Anyways... my "favourite" moment with infinite heights occurred once with E3M6, in the initial FIREBLU building. Trying to bypass and escape from the Baron, but unable to proceed through that window because of the monsters gathering down there. Funny that I still only almost died in the crossfire, I clearly remember having like 15 per cent life running back down the stairs.

Somewhat related, the speed of projectiles on the z-axis can be hilariously fast depending on the x/y distance & difference in height between the attacker and its target. Just another side-effect of Doom's "2.5D" nature.

I've noticed lost souls can suddenly ascend upward very quickly in source ports.

They did full 3D collision with projectiles. I wonder why they didn't with monsters and obstacles.

That's a good question.

Collision detection with non-solid objects is easier to do, because you don't need to handle shifting objects in case of collision (for example, if the player fell onto a monster and collided with it, shift him upwards on the level of the monster's height). Combining vertical and horizontal collision would be increasedly complicated if shifting was considered (and supposed to be as smooth as possible). Also, since it was impossible to look up and down anyway, maybe they (at least initially) didn't want the player to stand on top of enemies and things. That might be why the feature wasn't worked on with priority.

GoatLord said:

I've noticed lost souls can suddenly ascend upward very quickly in source ports.

We have a name for that: Quantum lost soul

It's simple, when you land on top of a monster they can easily swat your nutsack. Ouch OUCH!