Does anyone know how exactly efficiency is calculated?
I know it reduces charge consumption. I just wanna know in detail what you can expect from the numbers
As example, I thought it works like this, as the sample seemed to fit with the scenario.
I run Botany Knowledge with a yellow medkit. With the 24 charges I can fully heal twice and still have a tiny rest left over, so it would consume something about 11.x charges for a full heal instead of 16. My idea was instead of 1 charge per second, you consume 33% less with Botany Knowledge, which is 0,67 charges.
16*0,67 = 10,72 (would be close enough to 11.x, can't count the pixels after using the yellow medkit :) )
But either the other perks work differently or won't stack, or the calculation is not correct and just by chance very close. I tried the following: Run a brown medkit with Streetwise, Botany Knowledge and Selfcare, which is 33+25+20 = 78% so I thought 16*0,22 = 3,52 would take less than 4 charges for a full heal. But a brown medkit which would give me then a bit more than 4 heals just gave me a bit less than 3 heals
I tried it again without Streetwise, so 53% but with +8 charges, which gave me a bit more than 2 heals (so roughly took 11,x charges. In the same game, someone with an item build gave me the same medkit (brown with +8 charges) but additional addon for +16 charges. Using this medkit with 40 charges healed me not even twice, the first usage used up like 60% of the medkit. Which somehow makes no sense. So pretty sure we also have a bug here as well, and thinking about it, testing it doesn't give me a result knowing there is a bug XD
Does anyone know details, how it should be without bugs?
Comments
I think there is something weird going on with multiple addons or perks that use percentages on some value. For instance, I know there's some kind of order in which you have to put either the filanment first and then green battery on a flashlight to make it more efficient, or it's other way around, I don't know since I don't really use flashlights. I suspect the calculations use () parameters in the equations which would cause different results in different equip orders?
You were adding up those percentages in 33+25+20, but it might be that the different percentages affect eachother probably, somehow. I guess it should be the same thing.
I tried to make some calculations but didn't make sense to me after all and I have no idea what is happening in the code itself.
Percentages work individually, not cumulatively. So it's like 33 brings it down to 67, then it's -25% of that 67, so about 50, then -20% of the 50, so its final calculation would be about 40% of the normal consumption rate. So a brown medkit should be able to heal about 2 and a half health states.
If thats true then its the opposite of how percentages mostly work in this game, but its possible
I believe that percentage increases work cumulatively. Cuz individually, they would increase very quickly. Like stacking pwyf and noed
Did you only use the medkits in question on yourself? The Self-Care bonus to medkit efficiency only applies if you're healing yourself, not others.
@Fibijean Yes, only on me.
@DWolfAlpha What now, cumulative or not? :P Percentages on movement speed is a bit irritating I think. Adding 10% and another 10% woudlnt make you go to 121% ms because it is actually just a fix m/s value added. I also never understood how "running survivor" is set as 100%. They should just write 4m/s and add 0.2 m/s and so on. Btw your calculation isn't working as well, because I had the +8 charges. So it should be 3 full heals. But there is most likely a bug as well, when there is already the bug with the two items in the same game, where the more charges got consumed faster.
I see. Because I worked out what I think is the correct maths for the first two scenarios you gave, but the last two have me beat. Because you're right, if both medkits were at full charges when you started using them, and you only used them on yourself, and there was nothing like Coulrophobia or Sloppy Butcher or any Mangled add-ons in play, then I can't see any reason why 24 charges should heal you more than 40 charges with the same perk loadout.
Item efficiency and Action Speed actually work against each other. Botany knowledge is the perfect example of this.
If you're using a medkit, you'd think it would make you consume 0.33 charges less per second, but because you're contributing 0.33 charges more per second as well, it evens out back to 1 charge/second.
Thats not the problem. You spend the charges faster, but speed does not affect (or should not) how many charges you need to spend for a full heal
Is that how it works? I would think it would be more logical if the 33% efficiency bonus brought you up to 1 charge consumed every 1.33 seconds instead of every second, and then the 33% speed bonus would just make you consume less charges overall because the heal wouldn't take as long.So with the healing speed boost, at default healing speed, one full heal would consume about 12 charges with the efficiency boost at a rate of 1 charge every 1.33 seconds, but with the speed boost the heal itself would only take 12 seconds, so at the same rate of 1 charge every 1.33 seconds only about 9 charges would be consumed overall.But that's just my guess as to what "healing item efficiency" actually means, mathematically speaking, so if you have a source that disproves that I'd be very interested to see it.Nevermind, I think I've just understood what you're saying - that the charges gained from the efficiency bonus is the same amount as the seconds gained from the speed bonus, so the rate still ends up as 1 charge/second. Both effects do play a role in healing more quickly and efficiently, though, because you still end up with more charges in less time after a full heal.
What is your calculation? On the second one, I reported that as bug with screenshots. There were no other influences
It's really iffy and complicated and I've only recently been able to get a good grasp on the efficiency part of it.
Think of it as a bar that requires a certain amount of things to be filled.
Healing requires 16 charges. You have a yellow Med-Kit (which has 24 charges)
Self-Caring with a med-kit does not apply the speed boost, so you would be able to heal yourself 1.5 times over 24 seconds.
Take the same situation with Botany Knowledge.
You are now contributing 0.33 charges more (1.33c/s), but with item efficiency, you're not actually taking 1.33c/s from the Med-Kit, but 1.0 instead.
So what this really means is that you can heal 0.33 charges more per second, giving a total 1/3 bonus to your total charges, effectively giving your yellow Med-Kit 31.92 charges. However, you're still contributing more charges per second, so your heal takes 12.03 seconds instead of 16. This means you can heal yourself just barely under 2 times in about 23 seconds.
Yeah, I think I understood what you're saying. I edited my comment above after I realised my mistake. But thank you very much for the polite and well-reasoned explanation, it's much appreciated 😊
No problem. The whole charge system of dbd is really confusing and I'd love to spread the (botany) knowledge about it!
Don't worry about it - both fortunately and unfortunately, @AntiJelly helped me to see that I'd made a mistake in some of my calculations, so I'm still stumped, sorry 😕
But that is not correct. Botany + yellow medkit can heal you more than twice. There is enough left to fire a steptic or syringe.
But the idea is good, had that in mind as well. The "basekit" is: Put one charge per one second into one progress. A gen needs 80 progress, a healing needs 16 progress. For healing others and repairing every survivor has "unlimited charges", when using items you use the item charges.
Speed increases the middle value: putting one charge per'modified'seconds into progress.Speed should lower the middle value, but that gets complicated and not linear. To remember: a 100% speed increase does not mean you need 0% of the time, you need half of it. So lets say:
Speed increases the outer values: Putting 'increased' charges per one second into 'same increased' progress
Efficiency reduces the first value: putting 'modified' charges per one second into progress.
I wish there were more official information about it. I still don't think I really understand what the difference is, mathematically, between healing efficiency and reduced item consumption. I know there is a difference, but I don't know how each one is calculated beyond an educated guess.
@AntiJelly
So Botany Knowledge should do the following:
Only the efficiency: Put 0.67 charges per 1 seconds into healing progress
To remember: 100% speed means: Put 2 charges per second into 2 progress
So the speed does: 0.89 charges per second into 1.33 progress
That means, you need roughly 12 seconds to finish healing and spend roughly 10.7 charges
Are you sure there is a difference? I know they had several strange wordings like on flashlight addons, which should mean the same. And then stuff like enduring, when they said "75% faster recovery" to change it to "50% less stun time" because the first is simply causing knots in the brain to understand
I just noticed I have a difference in my explanation, need to edit it in the second last post
@Fibijean @Deadeye
I realized I've done my math wrong.
I think the problem is multiple modifiers don't play well together.
A self-caring Medkit plus Botany Knowledge in an isolated environment (just those two) works pretty well though.
Anyways, it should have been this:
Healing: 16 / (1.0 + 0.33) = 12.03 seconds to heal
MedKit: 24 / (1.0 - 0.33) = 35.82 charges in the med-kit
Each heal takes 12.03 seconds, but is still consuming those 16 charges. First heal removes 16 charges of the 35.82 effective charges in the med-kit. That takes you down to 19.82 charges effectively. Heal one more time, that brings you down to 3.82 charges left in the Med-Kit (effectively).
So Deadeye, you were right.
The issue is more modifiers (med-kit add-ons, efficiency perks, etc). They don't work like how I think they work, and I need to do more testing.
@AntiJelly If it helps, here are three screenshots. The first two regarding the bug, the third is a separate situation
You know, now that you mention it, I'm not actually sure that there is a difference. I thought that the phrasing was implying two different things, perhaps due to the contrast between "reduced" and "increased" in the two descriptions, but "efficiency" is actually a very vague word, and one could quite reasonably describe reduced item consumption rate as "increased efficiency". So I'm really not sure. I think the truth is those descriptions are just too vague for us to figure out concretely what the formula is, without the devs just giving it to us.
Those pictures actually help a lot. You didn't mention that the brown medkit you ran with all three perks had additional charges equipped, nor that an Abdominal Dressing was in play in the fourth scenario, which actually decreases the charges (you may have gotten it confused with the Gel Dressing). With that information, I'm going to redo the maths when I get home and see if I can figure out a solution for you.
DAMN! IT's THE WRONG ADDON XD -.-
But that's only to that thing. The calculation is still open and not fitting to what I expected regarding the screenshots 1 and 3 :P
But the new information has made me think that maybe I was on the right track with my calculations, so that's why I'd like to take another look at it when I get the chance.
Okay, so, I think I've figured it out. This is all based on the assumption that reducing item consumption rate is the same thing as increasing the item efficiency.
In the first scenario, with Streetwise, Botany Knowledge and Self-Care, Streetwise reduces consumption rate by 25%, which is the same thing as increasing efficiency by 1/3, because 16 x 75% = 16/1.33333... In other words, Streetwise increases item efficiency by 33.3333...%, which we'll round off to 33% for simplicity's sake. So with the combined effects of Streetwise, Self-Care and Botany Knowledge, medkit efficiency is increased to ~186%, so each heal will consume 8.6 charges (or maybe even 9 - I don't know if the game calculates charges other than in whole numbers). Since there are 24 charges on the medkit, this will give you just under three heals.
Without Streetwise, each heal would consume roughly 10.5 charges, giving you a bit over 2 heals.
The Brown medkit with Abdominal Dressing basically just has added healing speed. Both charge add-ons cancel each other out. So the medkit the other player gave you has 16 charges, and at the above rate of 10.5 charges per heal, a single heal would use up around 60% of the medkit's charges.
All of the above concurs with your description of events and what is displayed in your screenshots. Did I finally get it? 🤞
Ok so you mean wording might actually have impact on the calculation, meaning
Reduced consumption rate: Put less charges per one second into one progress
Increased efficiency: Put one charges per one second into increased progress
If this is the case, efficiency would in addition have a higher speed XD but I don't wanna drive it too far o.o How do you get from 25% reduced consumption to 33% efficiency?
@Fibijean And how do you calculate the 186% to 8.6 charges?
Btw I just checked again, I'm pretty sure they changed something recently. Because I can't think of always hitting at least one great skillcheck during 2 heals. Apparently just Botany Knowledge is a tap too less for 2 full heals on 24 charges. I'm 100% sure this worked before
Basically, I ignored the whole "charges per second" thing, because the fact that it isn't affected by things like speed boosters was just confusing my calculations, and thought of it in terms of "charges per heal" instead, with the standard being 16 charges per heal. I guessed that "increased effeciency" just means "takes less charges to heal". It probably amounts to the same thing, I just found it less confusing to look at it that way.
I also suspected initially that Streetwise and Botany Knowledge did two different things, the way you're saying, but what AntiJelly said above made me realise that maybe it's essentially the same effect for both, just worded differently. Which seems to be the case, since it led to apparently correct calculations.
How do you get from 25% reduced consumption to 33% efficiency?
Firstly, I assumed, as I explained above, that reduced consumption and increased efficiency were basically the same thing. Kind of like how saying "I'm going to make the water less cold" is the same as saying "I'm going to make the water warmer". As for the numbers themselves, that was just a matter of maths. If you know how to do basic fraction-based arithmetic, multiplying by 3/4 is the same as dividing by 4/3. So Streetwise both reduces consumption rate to 75% and thereby brings the efficiency up to 133%, and then adding on the 33% from BK and the 20% from SC, you get 186%. Then you divide 16 by 186%, because 16 is the base number of charges needed per heal, and you get 8.6, which is how many charges each heal consumes with the increased efficiency from the three perks.
I'm not sure if I explained that very well - I'm also finding it a bit difficult to wrap my head around - but I hope that makes sense.
Ok, makes sense, thank you.
Final result is definitely, that it is not worth spending 3 perks for that effect, if it barely gives you another heal XD. There's not much difference in 2 and a half heals and almost 3 heals, if you wanna heal yourself :P