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Run
22 Nov 2007, 22:16
what did this arrow in turn 3 hit?

i demand answers
Melon
22 Nov 2007, 22:36
Oh yeah I remember that match. That arrow was just crazy. wtf happened?

I demand answers too.
KRD
22 Nov 2007, 22:58
Curious indeed.

I vote for rounding error resulting in the arrow traveling for a frame after its "feathers" hit the top of that other arrow. Let's see what DC & CS have to say.
bloopy
23 Nov 2007, 10:35
If you single-step it you can see what's going on. It seems that in a frame where an arrow collides with the terrain, the arrow still moves a frame's worth of distance before coming to rest, no matter how close the arrow was to the terrain in the previous frame. In this case, the arrow was already halfway past the terrain in the previous frame, and the back of the arrow was extremely close to the collision. So in the frame where the collision happens, the arrow moves to its final resting place in mid-air. :cool:
Deadcode
23 Nov 2007, 10:47
Congratulations on finding such a bizarre glitch!

The longbow has very weird mechanics. Its collision mask is a single pixel, but every frame it checks against the arrow mask. So, it can either collide due to its arrow mask, or the pixels in between the gaps.

If it's the pixel mask that collides, the arrow doesn't instantly stop. It waits until the next frame to stop and embed itself. However, if it's the arrow mask that collides, then it instantly stops because it's already at a frame boundary.

I probably could have explained that better, but this picture should help. Notice that occasionally, the green pixels poke out from behind the longbow arrow mask. That is where this weird kind of collision can happen:
Melon
23 Nov 2007, 12:12
Wow. How extremely interesting.

I notice that the longbow actually starts it's collision check inside your worm. I guess this is why you hit yourself if you're standing right next to an enemy/wall when you fire.
KRD
23 Nov 2007, 12:20
I love these glitch threads. Two green pixels sticking out. Two! :eek:
bloopy
23 Nov 2007, 12:29
Silly of me to have thought that there might be a sensible explanation. Blame the pixel. ;)
AndrewTaylor
23 Nov 2007, 14:02
Does that image show every frame's arrow mask or every other frames? It looks like that would leave a lot of arrows entirely within walls and I've never seen that happen.
Splongul
23 Nov 2007, 14:24
I remember that glitch. I'd like to claim it lost me the game but I think my poor bowmanship is the real factor
Mr.Bad
23 Nov 2007, 17:46
Does that image show every frame's arrow mask or every other frames? It looks like that would leave a lot of arrows entirely within walls and I've never seen that happen.

the attached image also shows that the arrow could stop even far as in the replay (about 10 pixels more %)) but i also never seen that happen.