← Return to topic

Hitboxes of Projectiles

profae · 27 Jul 2026 at 22:26 · permalink

So, I'm trying to do an in-depth, data-based comparison of the projectile weapons, and all of the information seems to be readily available, except for the sizes of the projectiles' hitboxes. Does anyone know, or know a good source for this info? I don't mean the collision hulls of the classes. I know projectiles use the bounding boxes/collision hulls for collision detection. I am asking about the hitboxes of the projectiles themselves. As in, what are the sizes of the different grenades/rockets/syringes/arrows/etc?

Also, I've seen some people claim that Demo's grenades are unique from other projectiles and use the classes' hitscan hitboxes for hit detection instead of the collision hull. That doesn't sound right to me, and I can't find any actual reliable sources to verify it. Is this true?

maxAv3x · 27 Jul 2026 at 22:47 · permalink

The only thing that I know is that soldier's rockets are extremely tight, since they can be shot in the smallest gaps, and about demo's pipes idk, but that can be true, since pipes, as stickies, has hitboxes as actual boxes, unlike soldier's rockets

4ert225 · 27 Jul 2026 at 23:02 · permalink
Rockets have a size of 0 similar to hitscan. Arrows have a size of 1x1x1. I believe syringes do, too. Demo grenades have a fixed size of 4x4x4 when colliding with players. When colliding with the world, they use their physics shape, but there's some weirdness there (some grenade launchers use the same shape as stock despite looking different, etc)
Demo's grenades are unique from other projectiles and use the classes' hitscan hitboxes for hit detection instead of the collision hull
I believe you're thinking of stickies bouncing off players, they bounce off the player's actual hitboxes and not their hull.
hexx2008 · 27 Jul 2026 at 23:15 · permalink

arrows and syringes are 2x2x2 i believe

profae · 27 Jul 2026 at 23:26 · permalink

Thank you! This all makes sense to me. Rockets fly in a straight line, whereas things like arrows/syringes/grenades have arc. That'd make it really easy for rockets to calculate based on their travel down a ray, whereas the others need to be actual objects for physics calculation purposes. Arrows/Syringes being 1x1x1 Hu is just because that's the smallest possible size. Most grenades have tumble that affects drag, so they'd need to be bigger.

I assume other straight-firing projectiles like energy beams and
possibly Dragon's fury fireballs use rays like the rockets (I wonder if the Dragon's Fury uses a trace hull like melee so the fireballs feel bigger...), while Rescue
Ranger bolts behave like arrows and syringes. 🤔

The thing about stickies tracks, as well. I was actually wondering if the people who said the thing about grenades using the character hitboxes were getting them mixed up with stickies.

I might try my hand at scouring the SDK, and see if I can wrap my head around any of it. 🤣

4ert225 · 27 Jul 2026 at 23:27 · permalink

You're right, my bad, I saw the (1, 1, 1) in the code and didn't think about it properly.

profae · 27 Jul 2026 at 23:28 · permalink

Oh, right. They'd need to be 1 Hu along each axis from the center.

4ert225 · 27 Jul 2026 at 23:40 · permalink

Technically rockets are also objects just like the other projectiles, not rays, they just have a special move type that disables gravity and physics, and have their size explicitly set to 0 - here's how that's defined in the code. There's no minimum size.

Dragon's Fury projectile is special in that it's 2x2x2 when colliding with the world, but much larger (45x45x45? not sure of the exact value but it's around that) when colliding with players.

profae · 27 Jul 2026 at 23:43 · permalink

Oooh, interesting. 👀 Thank you.

MikuMiku001 · 28 Jul 2026 at 00:42 · permalink
Dragon's Fury projectile
i think it's basically coded as a "trigger" entity like how in many source games you can pick up hp or ammo drops from a farther distance, it's because they have a big "trigger bounds" that shows up as cyan in the debug overlay it's actually not uncommon for gmod addons to be bugged by not knowing how this trigger system works and they make it so the big trigger box blocks bullets and/or +use traces by doing the wrong collision setup btw as a note, the 2x2x2 is not the df's bonus dmg hitbox, it uses a line trace instead
MikuMiku001 · 28 Jul 2026 at 00:47 · permalink
stickies bouncing off players
something funny about this is that grenades actually have the same behaviour, but since the player model doesnt often stick out of the collision hull, it hits the hull first before it gets to hit a playermodel hitbox i think there was a plugin that changes player hulls for projectiles to be cylinders instead of aabbs and it ended up making grenades bounce off of enemies very often
profae · 28 Jul 2026 at 01:48 · permalink

This would explain why people got confused and thought grenades were an exception!