[G] ~8% faster gas mining

30 Apr. 2015 Added 4 new maps for 2015 Season 2
23 Feb. 2015 Added 8 new maps for 2014 Season 3 & 2015 Season 1
Added a link to an excellent research done by Sholip: The Reasons of Gas Mining Imbalance
27 Apr. 2014 Added 4 new maps for 2014 Season 2
13 Jan. 2014 Added HotS maps.
14 Jan. 2013 Added Akilon Flats and Newkirk District images.
02 Nov. 2012 Added Bel'shir Vestige and Metalopolis under Maps section. Added Other Sources section.
29 Oct. 2012 Added 2 more tables for much easier [gas/min] comparison at "More supplemental tables" under Research Results section. Edited Imbalanced Entombed Valley section accordingly.

Let me first talk about obvious facts:
1. There are 2 vespene geysers per base. (Ignore a few exceptions for now.)
2. CC/Hatchery/Nexus cannot be placed too close to vespene geysers.
3. Relative locations of 2 vespene geysers to CC/Hatchery/Nexus depend on the resource layout of each base.
4. T/Z/P race requires Refinery/Extractor/Assimilator, respectively, built on top of a vespene geyser in order to mine gas from it.
5. Workers need to be assigned to mine gas from these facilities. 1 trip mines 4 gas. (For the sake of easier discussion in this thread, ignore high yield gas = 6 gas per trip.)
6. Generally speaking, assigning 3 workers per gas is the most efficient.
7. After total of 2500 gas is mined = 625 trips, a vespene geyser depletes.
8. Rate of mining is not dependent on the race played.

So, how does one mine gas faster? It all boils down to this simple fact:
At some diagonal angles to CC/Hatchery/Nexus, the location of a vespene geyser is so far that 3 workers cannot mine as efficiently as at other non-diagonal closer vespene geyser locations. At these diagonal angles, a worker emerges out of the gas mining facility before the next worker arrives at it, while maximum efficiency means that the next worker waits right next to the structure for the prior worker to emerge out.



OK, some of you have been aware of this fact even from the days of Metalopolis like the picture above. As I said, there is no new “trick” that I show you here. Basically, you can mine gas faster simply by having a spawning location on a map without these far diagonal vespsne geysers. Question is, among a few hundred vespene geyser locations in the current map pool, which ones are far diagonal and which are not? Let's not jump to the conclusion. There are still some things you must learn to fully understand the map images 3 sections below.

Far, close, diagonal etc. are all vaguely defined terms. Therefore, in order to study further, locations must be defined in more scientific way with no ambiguity. Vespene geyser is a 3X3 neutral structure, so using the center grid to denote the location should make sense. Also, CC/Hatchery/Nexus must be at a certain distance away, yet as close as possible. My research has found that there are only 48 locations available for vespene geysers relative to CC/Hatchery/Nexus, all of which can be categorized into 7 different groups (A~G). Numbers in the image show the angles in degrees. Basic math knowledge is expected.



Image above must be pretty much self-explanatory. Since everything is square-based and symmetric, categorizing everything within 45 degrees makes discussion much easier. Remember again, that A~G are just the center grid of the 3X3 vespene geysers. So, in reality, all 8 adjacent grids (just like King's movement in Chess) are also occupied. Apparently, there is no way 2 vespene geysers of a base can be, say, B and C right next to each other because 2 structures cannot occupy the same grid. Black 5X5 CC/Hatchery/Nexus is fully shown.

Naming Rule
A~E: use alphabet + range of degree
[A,0-45] shows A within 0-45 degeres.
[C,225-270] shows C within 225-270 degrees.

F,G: use alphabet + exact degree.
[G,90] shows G at 90 degrees.
[F,315] shows F at 315 degrees.

For example, [D,90-135] cannot coexist with [F,135] because their surrounding grids overlap.

Example image: [B,180-225] and [E,45-90] at Cloud Kingdom bottom spawning location natural base.

Which ones are “far" vespene geysers? To find out, I just mined at all those 48 different locations with 3 workers each. Easy to say, but it took years to finish the work. I double/triple checked all numbers, so margin of error is 1-2 seconds maximum. Numbers in the following table shows how many seconds it takes for 3 workers to mine out 2500 gas:


Coloring the earlier image according to the result above: (1291=most efficient=blue)


Non-blue locations are so-called “far diagonal” locations where 3 workers mine inefficiently. 1291 seconds = blue locations = standard/efficient/optimal mining. 1291 is a useful number to keep in mind as I will keep calling blue locations “1291 (standard) gas” and other locations "inefficient gas" later in this thread. What surprised me was that the result was not symmetric. Prior to the research, my hypothesis was that locations with same alphabet have exactly the same mining time. However, after double, triple, quadruple checking, there is no denying that these numbers are true and each D,E,F location has different efficiency, ignoring the symmetry. I tried to come up with a mathematical model to explain this asymmetric nature, but I gave up due to too much randomness. Whatever reason there might be, the results are true anyways.

Supplemental tables:
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More supplemental tables:
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As you can see, [E,0-45], [E,180-225] and [E,225-270] are the most inefficient ones which take as much as 104 more seconds to mine out and mines as inefficiently as 92.5% compared to 1291 standard gas locations. Loss is 8.7 [gas/minute] in these cases.

The results above are totally useless if you don’t know which vespene geyser on a map is categorized into which. In the following map images, bold letters inside spoilers mean that these locations are non-1291 inefficient gas. Refer to map and table to find out location/exact inefficiency if needed.

Akilon Flats

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Newkirk District

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Antiga Shipyard

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Cloud Kingdom

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Condemned Ridge

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Daybreak

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Entombed Valley

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Ohana

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Shakuras Plateau

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Tal’darim Altar

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Whirlwind

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Abyssal City

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Bel'shir Vestige
Bel'shir Vestige research is done with the map currently available on battlenet. Image originaly released by GOMTV has different gas locations. I'm not 100% sure which verstion is played at GSL, but I assume that they modified gas locations after the image release, and the one released on battlenet is the newer correct version. (Edit: yes, this is the case. GSL gas locations are the same as my coloring.) Because of this, I completely ignored the gas locations in the image and colored sololy based on my research.

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As you can see, majority of gas locations are 1291 standard gas which can be mined optimally with 3 workers. However, all maps have inefficient gas locations as well: minimum = 1 on Ohana, maximum = 11 on Condemned Ridge, and maximum among tournament maps = 10 on Entombed Valley. Just for reference, good old Metalopolis had 10 as well when it had 4 less bases = 8 less gas locations than Entombed Valley. Having 10 / 24 gas in total on Metalopolis = 41.7% “far” vespene geysers is probably the reason why Metalopolis gas imbalance was easier to notice. Look how colorful Metalopolis is.
Metalopolis

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Echo ~2015 S2


Expedition Lost ~2015 S2


Vaani Research Station ~2015 S2


Inferno Pools ~2015 S2


Secret Spring ~2015 S1


Catallena ~2015 S1


Deadwing ~2015 S1


Overgrowth ~2015 S1


Foxtrot Labs ~2014 S4


Nimbus ~2014 S4


Merry Go Round ~2014 S4


King Sejong Station ~2014 S4


Waystation ~2014 S2


Habitation Station ~2014 S2


Alterzim Stronghold ~2014 S2


Frost ~2014 S2


Daedalus Point ~2014 S1


Heavy Rain ~2014 S1


Polar Night ~2014 S1


Yeonsu ~2014 S1


Star Station TE ~2013 S6


Derelict Watcher ~2013 S6


Bel'Shir Vestige ~2013 S6


Akilon Wastes ~2013 S5


Whirlwind ~2013 S5

In Feb. 2015, Sholip's outstanding research post, The Reasons of Gas Mining Imbalance, explains in detail why this gas imbalance exists.
It concludes that units' movement properties depend on the angle they are facing. What a surprise!

Nope. This is not about Protoss imba on Entombed, or any X race imba vs Y race for that matter. To avoid race vs race balance discussion for the moment, let’s just limit discussion to PvP. Why not ZvZ or TvT? Because larvae always spawn on the south side of a hatchery = asymmetry/imbalance in ZvZ or add-ons always have to be on the right side = asymmetry/imbalance in TvT. There is no such thing in PvP, so it is the fairest match-up so to say, although following gas imbalance argument also applies to non-PvP match-ups to a slightly lesser degree due to other imbalance factors. Now, of course this is about gas mining. Take a look at the Entombed Valley again.


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Entombed Valley is so imbalanced in terms of gas mining in that
1. all main bases have one inefficient gas with varying degrees of efficiency.
2. all natural bases have one inefficient gas with varying degrees of efficiency.
3. only two 3rd bases out of four have one inefficient gas.
Therefore, all of 1base vs 1base, 2base vs 2base, 3base vs 3base… have different rates of gas mining between players. That is, 2 players can never be equal even in the fairest PvP where they execute exactly the same build without even a 0.00000001 second timing/positional difference. If cloned 2 players with perfectly same skill were to play PvP on Entombed Valley, the one who got a favorable spawning location always wins just because of the gas imbalance. Here are the examples:

1base vs 1base (1gas vs 1gas)
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1base vs 1base (2gas vs 2gas)
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2base vs 2base (4gas vs 4gas)
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3base vs 3base (6gas vs 6gas)
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7 o’clock spawning location is OP no matter what race you or your opponent play. 2.1% - 1.5% - 1.1% lead all the way to 3 bases is a huge deal, especially when we talk about mirror match-ups. I would love to know win rate not just by map, but by spawning locations. Statistically speaking, 11 o’clock vs 7 o’clock mirror match-ups on Entombed Valley has to favor 7 o’clock player. At least for PvP for the reasons I mentioned above, 7 o’clock has no disadvantage vs 11 o’clock or even vs 1 or 5 o’clock actually. Find your opponent at 7 o’clock into QQ is the new PvP metagame. (make it happen ) Other maps have gas imbalance as well, but Entombed Valley looks the worst at the moment unless anyone is still playing unpopular Condemned Ridege.

Maybe this resource distribution is not enough to convince you, but once you have like 2000+ mineral & almost 0 gas, I think it is time to think about sending 4th worker to all those inefficient non-1291 gas locations you have to mine gas faster. At this point, loss of some mineral mining is insignificant compared to the gain by having slightly better gas mining rate overall. Remember that sending 4th worker to those blue 1291 standard gas locations does absolutely nothing. They are already fully saturated with 3 workers. Refer to (or just remember if you are taking this game seriously like a pro) the map images so that you know which gas locations actually benefit from the 4th mining worker. Benefit varies from 1.0%~8.1% each location, but mitigation by several other 1291 gas you have means that the benefit to overall economy is usually less than 1%, which still is better than accumulating another millions of minerals. Always deal with the limiting resource of your build just like chemists do with their “limiting reagent.” What’s abundant is never an issue in both cases. Don't buy oxygen tank to grill meat. Oxygen is already plenty in the air. Buy more meat.

Please stop taking inefficient gas in your main, notably on Entombed, as your first gas because at least one of the two is always 1291 gas for all bases we have today. It’s OK that you’ve done it up until now, but it is inexcusable from now on. There is no drawback in taking 1291 gas. No additional micro whatsoever is required to do so. 8.1% potential mining loss is by no means a small thing when playing at pro level. From what I’ve seen, some pros are already aware of the obvious far gases and actively avoiding them, but there are other pros who aren’t yet. Please step it up.

In ZvP, many Zerg players today take 2 gases around 6:00 at natural instead of main not to disturb optimal 16 mining drones in main mineral line. I understand the logic, but is it always worth it? In fairly recent games, I saw Losira and DRG did this on Entombed 11 o’clock and Antiga 8 o’clock, respectively. Both natural bases include relatively highly inefficient red colored gases. Had they taken two 1291 gases by taking 1 in main and another in natural, they would have mined gas about 4% more efficiently. I’m not so sure how important not disturbing the mineral line is, but it seems that 4% for gas is significant enough to consider when pros like them have enough APM to handle early game task like this. I'm not talking about something like 1% gain at 15min mark when you can never have enough APM, but it’s about 4% at 6~7min mark when things are calm with 200APM. I can’t handle 6min mark myself T_T, but pros should be able to. I would love to see top pros actively avoid inefficient gas. Zerg has 3base = 6 gas locations to choose from at that point.

Or, just generally for any match-ups, please learn which ones are safe blue ones. Then, prioritize taking these before non-blue ones whenever possible. I know that there are tons of other important things to do in game, but it’s never a bad thing to learn a way to increase your income with no additional micro whatsoever. At the very least, GSL/OSL level players need to learn this as they are competing for tens of thousands of dollars. You can never take the game serious enough then. Please don’t disappoint me by taking gas randomly in GSL/OSL finals. It should never happen again.

All I can say for Blizzard is, “fix it.” At the very least, the symmetry among the same alphabet locations needs to be kept in my opinion, but I know it’s not going to happen in any foreseeable future. I posted a glitch 7 months ago in Larva disappearing Glitch (not about 20th larva), but nothing has happened yet. When there are bigger issues like HotS, LAN, name change(???) etc., I don’t think they would ever work on this relatively minor issue that some players didn’t even know before opening this thread. Take your time, Blizzard. I love this game so much anyways that I have spent months doing multiple researches linked at the end of this post.

Since gas mining inconsistency will stay without Blizzard’s intervention, I would like mapmakers to avoid using E and F gas locations when designing a base. As Ohana has shown, it is possible to design a good base layout without E or F. Ohana has one inefficient [D,45-90], but symmetry of the map force one 1291 D on the other side of the map to be one of inefficient [D,45-90] or [D,90-135]. Not having these would be nice as well, but you can’t help it sometimes. Also, it would be nice to at least keep symmetry of the gas locations. For example, Cloud Kingdom natural bases have different alphabets for top and bottom.
Top natural [C,0-45] and [D,225-270]
Bottom natural [B,180-225] and [E,45-90]
In order to keep the symmetry of the map, I feel that bottom natural should have been [C,180-225] and [D,45-90] = exactly 180 degrees rotation from top natural. Ohana and some other maps also have rotationally asymmetric gas layout like this for some reason.

The Gas Issue, second edition
This is a similar research on this gas issue done by spinesheath during beta days(!) in 2010. Unfortunately I didn't know about this research until people posted the link in this thread. Although this research lacks some accuracy supposedly to save time, it is remarkable in that spinesheath did it at very early stage of SC2 and that it includes 2 worker mining research that I skipped. I wish I knew about this research. It would have saved me a lot of time following spinesheath's lead instead of doing everything all on my own.

Wow, I wish writing for my real life responsibility were as fun as this one. I guess some of you remember me, Orek, from various other research posts. I posted 10 other guides/articles before, but this was by far the toughest one. Both research and writing took a long time. With my poor English vocabulary, I might have repeated the same word too many times, but I believe most things are clear enough in this thread. Was the title misleading? Well, I tried to make it as attractive as possible while avoiding being downright lie. At this point, you are probably thinking, “well, this thread was not exactly what I was expecting to read from the title.” I did my best to satisfy those who I intentionally mislead by the title I know that the topic here is not the biggest deal in the whole world, but most of my topics aren’t if you know my previous posts. However, at least among my posts, I consider this gas mining research the best contribution to the community I have made so far, or possibly 2nd best to [G] Zerg Sim City for Spire protection in ZvP for fellow Zerg players.
OSL final spoiler inside
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Similarly, I hope top pros pay some attention to this gas mining research work. I don't think translation of entire thread is necessary. With a little help in understanding the overall concept, images must be self-explanatory just like the spire protection thread. I'm the one who did all this research, but sadly, I am too scrubby of a player to benefit from small gas gain myself Top pros are the ones who benefit the most from this. I forgot to include 2 strong retard viewer magnets: race balance discussion and dramacraft, but I hope this thread gets enough attention of people who actually care about the SC2 gameplay itself. Any feedback/correction/verification is much appreciated. After all, no one else has confirmed any of the facts I presented here yet as of writing. Thank you for reading.