Game Mechanics Quiz 1 - How much do you really know?

[UpperKEES]

You have to stick to your own rules.  ;)

Yep, and I do that (which has cost me a gold tournament medal as you know).

I wasn't sure however if others would get that close to the answer, but the accuracy surprised me to be honest.

[UpperKEES]

6:50?

Please tell me which question you're trying to answer....

[Blaze]

I revoke my answer!

I thought it was for the new one, it's late and I miss-read it. :D
I base my guess on others, sorry, but I go with a gut feeling as well.
I use the others answers to give me a smaller range to guess upon.

[UpperKEES]

I use the others answers to give me a smaller range to guess upon.

Well, that turned out a smart thing to do. :)

I thought it was for the new one

I'll post the next question on Monday. Probably the last one, unless Sqaz makes it a tie.

[Blaze]

I use the others answers to give me a smaller range to guess upon.

Well, that turned out a smart thing to do. :)

I thought it was for the new one

I'll post the next question on Monday. Probably the last one, unless Sqaz makes it a tie.

I look forward to seeing the victor.
I know it won't be me, I only got one point. :P

[mthw2vc]

An interesting side issue:
When processing the game frame by frame you'll notice another remarkable thing: when an emitter emits, the creeper from that cell will spread to all neighboring cells 8 frames later, but no creeper is left in the center! You can clearly see this in the creeper clock for frames 2 to 8. Again 8 frames later the creeper flows back from the neighbors to the center cell. You would never see this behaviour with heat or fluids spreading, but it explains why you can see the emitters flashing during the game (I always wondered why).

I also noticed this (Even without advancing frame-by-frame). "But I didn't say anything."

Essentially, what happens when the creeper updates (Barring terrain and walls) is that it sets the creeper value of a cell to the average thickness of the surrounding cells, not even taking into account the current cell. Creeper can't flow through walls, so the creeper that would have flowed into a wall is redirected to the original cell, and a similar rule applies for terrain differences. The flow of creeper is, as with heat, directly proportional to the gradient. The fact that a cell keeps none of its original creeper if surrounded by empty space is an effect of cranking up the spread rate as high as the formula allows without increasing how often the calculations are performed.

[UpperKEES]

Ah, so it's basically an optimization issue? Not that it really matters, because the cell is only empty for 8 frames (instead of one, due to another optimization), so it doesn't affect gameplay at all.

By the way: this slightly changes the explanation of the answer to question 1 of this quiz, but not the answer itself.

Thanks for the addition! :)

Edit: now I think of it: this also means the wall element with the survival pod gets exposed to the creeper 8 frames less, because the cell containing the emitter was empty for that duration. This makes it very likely that 14688 frames (exactly 408 seconds) is the correct answer to question 9. Nate Dog gave this answer, so I decided to award him with a point as well. My apologies! Blaze can keep his, because I should have made a better testmap.

As a result these are the exact decay times for wall elements:

A wall element with 2 sides exposed to the creeper will decay in ¹/₂ x 14688 = 7344 frames = 204 seconds.
A wall element with 3 sides exposed to the creeper will decay in ¹/₃ x 14688 = 4896 frames = 136 seconds.
A wall element with 4 sides exposed to the creeper will decay in ¹/₄ x 14688 = 3672 frames = 102 seconds.
A wall element with 5 sides exposed to the creeper will decay in ¹/₅ x 14688 = 2938 frames = 81.6 seconds.
A wall element with 6 sides exposed to the creeper will decay in ¹/₆ x 14688 = 2448 frames = 68 seconds.
A wall element with 7 sides exposed to the creeper will decay in ¹/₇ x 14688 = 2099 frames = 58.3 seconds.
A wall element with 8 sides exposed to the creeper will decay in ¹/₈ x 14688 = 1836 frames = 51 seconds.

I'm glad we got that straightened out.

Edit 2: see here for more corrections regarding this topic.

[Blaze]

"But I didn't say anything."

                                                  p(-_-)q

[ontheworld]

"But I didn't say anything."

                                                  p(-_-)q

I repeat: Forums are just more fun that way.

[mthw2vc]

Edit: now I think of it: this also means the wall element with the survival pod gets exposed to the creeper 8 frames less, because the cell containing the emitter was empty for that duration. This makes it very likely that 14688 frames (exactly 408 seconds) is the correct answer to question 9. Nate Dog gave this answer, so I decided to award him with a point as well. My apologies! Blaze can keep his, because I should have made a better testmap.

As a result these are the exact decay times for wall elements:

A wall element with 2 sides exposed to the creeper will decay in ¹/₂ x 14688 = 7344 frames = 204 seconds.
A wall element with 3 sides exposed to the creeper will decay in ¹/₃ x 14688 = 4896 frames = 136 seconds.
A wall element with 4 sides exposed to the creeper will decay in ¹/₄ x 14688 = 3672 frames = 102 seconds.
A wall element with 5 sides exposed to the creeper will decay in ¹/₅ x 14688 = 2938 frames = 81.6 seconds.
A wall element with 6 sides exposed to the creeper will decay in ¹/₆ x 14688 = 2448 frames = 68 seconds.
A wall element with 7 sides exposed to the creeper will decay in ¹/₇ x 14688 = 2099 frames = 58.3 seconds.
A wall element with 8 sides exposed to the creeper will decay in ¹/₈ x 14688 = 1836 frames = 51 seconds.

I'm glad we got that straightened out.

No...

Creeper can't flow through walls, so the creeper that would have flowed into a wall is redirected to the original cell, and a similar rule applies for terrain differences.

If you pause as the creeper first spreads, there is 3/8 of a layer of creeper over the emitter and touching the wall, assuming the emitters are intensity 1. Your original answer was correct.

[UpperKEES]

The creeper only updates every 8 frames, so unfortunately our display is not always up to date, making this rather hard to test. Maybe when you shift the starting frame of the emitter by a few frames you would be able get a better view on it. This can be achieved by manually adjusting the start time by 1 frame using this info, but I am kind of done with this question.

Besides that I think it makes sense that Virgil chose a round number for the default decay time and 408 seconds can be divided by 2, 3, 4, 6 and 8, so that seems a rather logical choice. Only Virgil knows the real answer, but I don't want to bother him for every single quiz question. Anyway, the correct answer seems to be between 14688 and 14700 frames, so I think it's fair that both people who answered within that range earned a point as I shouldn't have asked for such a precise answer while I couldn't be this precise myself (due to the program optimizations that I initially didn't take completely into account).

[mthw2vc]

I'm not asking you to look at what you see directly on the game screen itself. I use the value shown at the bottom of the screen in the elevation display, which is always more up-to-date rendering you see in the main game area, and takes into account changes in the creeper grid before any recalculations, responding instantly to the damage caused by a weapon or an emitter firing. Advancing frame-by-frame, the moment when the creeper first spreads outward from the emitter in the attached map, there are 3 units of creeper on top of the emitter and 1 in each of the adjacent empty squares.

[UpperKEES]

Question 10 has been posted. :)

[Aurzel]

I'm not going to look at the maps but just by looking at the picture you put up I'm going to guess that the emitter in the middle has a shorter interval  in the unsuccesful map, causing the blaster on the right to focus its fire on the emiter in the middle instead of on the emitter on the right (due to very fast interval emitters needing 2 blasters to cap it) this will allow creeper to spread on the right and destroy collector there, thus preventing the win

[Sqaz]

The blaster placed last will target the middle pool, this causes the difference.
Why? Probably because the last placed blaster starts with checking where the creeper is, and thus will shoot at the middle pool, the other one can't fire there, cause there isn't any creeper left, so it shoots at one of the side pools, I guess.