Editing Technology

{{Version|2.8}}
{{Technav}}
''Technology'' in Stellaris is divided into 3 research areas with each area corresponding with one of the research resources: {{iconify|Engineering|21px}}, {{iconify|Physics|21px}} and {{iconify|Society|21px}}. Additionally, each of the ~300 techs belongs to one of 12 subcategories divided between the areas (most appearing pre-dominantly in one area though not exclusively).

The user interaction aspect utilizes a ''card shuffle'' approach rather than a traditional ''tech tree'' presentation, thereby introducing an element of semi-randomness into the system.

== Research areas & fields ==
{{SVersion|2.8}}{{anchor|Categories}}
[[File:UI tech.png|right|thumb|400px|Technology interface. Every slot here can have one research project active at a time and every research area has its own slot.]]
There are three different main ''research areas'' in-game, with each area corresponding with one of the research resources. Additionally, each research area has multiple subcategories, for a total of 12 such subcategories, and every tech belongs to one of these subcategories.

The areas and their subcategories are as follows:

'''{{icon|Engineering}} [[Engineering research]]'''
:* {{iconify|Industry|21px}}: Mineral production and storage, robots, building construction.
:* {{iconify|Materials|21px}}: Armor, strategic resources.
:* {{iconify|Propulsion|21px}}: Kinetic and explosive weapons, thrusters.
:* {{iconify|Voidcraft|21px}}: Ship types and hulls, starbases, strike craft.

'''{{icon|Physics}} [[Physics research]]'''
:* {{iconify|Computing|21px}}: Science Labs, research, science ships, ship computers, point-defense, sensors.
:* {{iconify|Field Manipulation|21px}}: Power Plants, shields, some strategic resources.
:* {{iconify|Particles|21px}}: Ship reactors, energy weapons, FTL, some strategic resources.

'''{{icon|Society}} [[Society research]]'''
:* {{iconify|Biology|21px}}: Food production, leader lifespan and policies, species modification, army types, some strategic resources.
:* {{iconify|Military Theory|21px}}: Fleet command limit, naval capacity, army buildings and statistics, claim cost.
:* {{iconify|New Worlds|21px}}: Tile blocker clearance, terraforming, starbase capacity, administrative capacity.
:* {{iconify|Statecraft|21px}}: Unity, edicts, leader pool and recruitment, planetary and empire capitals.
:* {{iconify|Psionics|21px}}: Exotic mid- to late- game technologies. Unlocked through the {{icon|Psionic Theory|24px}} {{tech|rare|Psionic Theory}} technology.

== The card system ==
{{SVersion|2.8}}
[[File:Card system.png|thumb|400px|The "card" system. Every time a research project is to be initiated, the game will draw a hand of cards like this one from which the player then can pick one technology to research.]]
Although the underlying technology system is based on the familiar ''tech tree'' structure, it does away with its standard interaction/presentation in favor of the ''card shuffle'' approach. This injects a semi-random element into research, making it somewhat less predictable as well as more non-linear.

Whenever the player is prompted to initiate a research project, the game gives them a "hand of cards" consisting of a semi-random selection of technologies available for research which are picked randomly from a hidden "deck of cards" consisting of all valid research options that can appear.

Every time the player meets the requirements for a given technology to become obtainable, the technology in question is added into the main "card deck" and will then have a chance of appearing in the "card hand" whenever the game draws a new hand for the player to pick from. There are two basic parameters affecting a tech's chances of appearing in a given card hand:

* ''Tiers'' – Technologies are divided into 6 levels (T0 to T5) of advancement. Higher tier technologies require obtaining a certain number of technologies from the preceding tier in the same area of research (set at 6 for all tiers<ref>See {{path|common/technology/tier/00_tier.txt}} for details.</ref>) before they become available as research alternatives.
* ''Weight'' – A base value denoting the ''relative'' chance (out of all the valid options) of a particular technology to be drawn as an alternative. This may be further modified by an empire's composition (ethics, civics, etc.) and its current state (scientist's traits, past tech, etc.).

To further increase variation, a tech which appeared as an alternative in the previous card hand will have its weight set to 0 in the next prompt.

As a general rule of thumb, the more advanced a technology is, the lower its weight (and the higher its cost). Systematically important techs (e.g. terraforming) have a higher weight (typically between 150% and double normal) to help ensure empires get a chance to research them, whereas {{tech|rare|rare technologies}} have significantly lower weight (typically one-eighth normal without the matching expertise). Some factors increase the weight of rare techs:
<!-- These factors are omitted from [[Society research]] because they're (almost) universal. Don't put other modifiers here e.g. expertise because they vary. -->
* Being in a level 3 or higher [[File:Federation research.png|21px]] Research Cooperative [[federation]] with another member who knows the tech doubles the weight.
* The [[File:Ap technological ascendancy.png|21px]] Technological Ascendancy ascension perk increases the weight of {{tech|rare|rare technologies}} by 50%.

=== Example ===
Let's assume the game draws a card hand of 3 techs: {{icon|Armored Torpedoes tech|21px}} Armored Torpedoes, {{icon|Autocannons tech|21px}} Autocannons, and {{iconify|Exotic Gas Refining|21px}}. Additionally, the lead engineering scientist has a {{iconify|Propulsion|21px}} field expertise (matching Armored Torpedoes) and the previous card hand had {{icon|Autocannons tech|21px}} Autocannons as an available option.

<math>\text{Total weight} = \text{Armored Torpedoes weight}\, \cdot\, \text{expertise bonus} +\, \text{Autocannons weight}\, +\, \text{Exotic Gas Refining weight}</math>

<math>\text{Total weight} = 75 \cdot 1.25\, +\, \frac{75}{2}\, +\, 170 = 93.75 +\, 37.5 +\, 170 = 301.25</math>

If these were the only three valid techs and only one tech were to be drawn, then each tech's chances of being drawn would be '''29.1%''', '''12.5%''', and '''56.4%''' respectively (rounded to 1 decimal place). Realistically there are usually many more valid picks and so the probability of picking any given tech is significantly lower than the figures given here.

=== Research alternatives ===
{{SVersion|2.8}}
Each card hand drawn will contain 3 research alternatives, which may be further increased by 1 for each of the following:
* {{icon|edict}} Scientific Revolution unity ambition
* {{icon|self-evolving logic|24px}} Self-Evolving Logic technology
* [[File:Tradition_discovery_science_division.png|24px]] Science Division / Mindlink / Research Path Optimization discovery tradition
* {{iconify|Natural Neural Network}} civic
* {{iconify|Static Research Analysis}} civic
* {{iconify|Research Cooperative}} level 2

Additionally, some research cards may be gained as ''permanent alternatives''. They appear below the regular alternatives and are distinguished from them by a {{tech|acquire|golden}} border surrounding the tech card's bezel. These alternatives are usually acquired (along with some partial progress) through post-battle debris analysis, from special projects or [[event]] chains. These options will always appear as available options when drawing a new card hand and will remain as such until completed.

If need be, it is possible to change an on-going research project at any point - without incurring penalties - in order to continue researching it at a later time. It is important to note, however, that the saved progress does ''not'' scale with changes occurring to technology costs (for better or for worse). This tends to lead to the tech's completion percentage getting lower as the empire continues to further exceed its administrative capacity.

As opposed to a permanent alternative, there is no guarantee that the technology in question will appear in the next card hand drawn.

== Research output ==
Each ''research area'' employs the use of a different research resource. 

Each of these individual resources has a base production of {{green|5}} research points a month. This can be further increased by pops working the appropriate [[Jobs]] or {{icon|module|21px}} [[Construction#Research_Stations|research stations]] on the galactic map.

The research production may then be modified by the following:
{{bonus table|Research output|collapse=yes}}

Additionally, each of the resources may also have the following modifiers affecting them (these apply only to a single resource rather than to all of them):
{{bonus table|Engineering output|collapse=yes}}
{{bonus table|Physics output|collapse=yes}}
{{bonus table|Society output|collapse=yes}}

=== Stored research ===
Research output which is not being used for research at the time is being accumulated as ''stored research''. Alternatively, it may also include research resources gained from other avenues such as debris analysis, anomalies, events, and etc.

This method allows for a more "relaxed" research by eliminating the loss of research points due to forgetting to pick a research project while, at the same time, also simulating accelerated periods of research (as opposed to sudden "jumps") caused by newfound knowledge sources. The current storage levels can be seen by hovering over the appropriate resources.

The expenditure rate of stored research can be expressed as follows:

<math>\text{Stored research expenditure length} = \frac{\text{Research resource stored} }{ \text{Research resource produced}}</math>

;Example
An empire produces {{icon|eng|21px}} {{green|+24}} Engineering research a month and has just finished debris analysis granting it {{icon|eng|21px}} {{green|+1000}} Engineering research (stored research).

<math>\text{Stored research expenditure length} = \frac{\text{1000}}{ \text{24}} =\, \text{41.67 months}</math>

The empire will supplement its {{icon|eng|21px}} Engineering research by an additional {{green|+24}} research points for the first 41 months and by another {{green|+16}} research points in the following month, after which the {{icon|eng|21px}} Engineering stored research bank will completely deplete.

== Research speed ==
{{SVersion|2.8}}
''Research speed'' represents a given expertise in a particular research area or field leading to shortened research time of related technologies.

Research speed boosts the perceived research production in the following manner:

<math>\text{Perceived research production} = \text{Research resource produced}\, \cdot\, \sum\text{Research speed modifiers}</math>

The most immediate sources of research speed modifiers are the 3 lead [[scientists]]. As the applied bonus depends on a scientist's skill level and overall traits, it is recommended to assign newly recruited scientists to command a [[science ship]]. Scientists on exploration duty tend to gain experience faster and, if one is in luck, they may also gain a new trait beneficial to research while leveling up.

; Example
An empire is a {{iconify|Materialist|21px}} and produces {{icon|eng|21px}} {{green|+24}} Engineering research a month. It has a lead engineering scientist with a {{iconify|Propulsion|21px}} field expertise while researching {{icon|Armored Torpedoes tech|21px}} Armored Torpedoes.

<math>\text{Perceived research production} = 24\, \cdot\, (1\, +\, 0.05\, +\, 0.15)\, = 28.8 </math>

'''Note:''' A research area without an acting lead scientist receives a penalty to research speed.

Research Speed can be affected by the following:
{| class="mildtable"
! Source
! Research Speed
|-
| {{icon|edict}} Scientific Revolution ambition
| {{green|+20%}}
|-
| {{icon|edict}} Nanite Actuators edict
| {{green|+10%}}
|-
| {{icon|agenda}} Scientific Leap agenda
| {{green|+10%}}
|-
| {{icon|tradition}} Discovery tradition tree finish
| {{green|+10%}}
|-
| [[File:Ap technological ascendancy.png|24px]] Technological Ascendancy ascension perk
| {{green|+10%}}
|-
| {{iconify|Fanatic Materialist}} ethic
| {{green|+10%}}
|-
| {{iconify|Materialist}} ethic
| {{green|+5%}}
|-
| {{iconify|Administrative AI|24px}} technology
| {{green|+5%}}
|-
| {{iconify|Positronic AI|24px}} technology
| {{green|+5%}}
|-
| {{iconify|Erudite}} ruler trait
| {{green|+5%}}
|-
| [[File:R galaxy.png|24px]] Miniature Galaxy relic
| {{green|+5%}}
|-
| [[File:Tech science nexus.png|24px]] Science Nexus megastructure (stage I)
| {{green|+5%}}
|-
| [[File:Tech science nexus.png|24px]] Science Nexus megastructure (stage II)
| {{green|+10%}}
|-
| [[File:Tech science nexus.png|24px]] Science Nexus megastructure (completed)
| {{green|+15%}}
|-
| [[File:Enclaves flag curator.png|24px]] Curator Insight empire modifier
| {{green|+10%}}
|-
| {{icon|lev}} The Singularity Procesor empire modifier
| {{green|+5%}}
|-
| {{icon|lev}} The Mirror of Knowledge empire modifier
| {{green|+10%}}
|-
| {{icon|fed}} Spurred by the Past empire modifier
| {{green|+5%}}
|-
| {{icon|fed}} Full Circle empire modifier
| {{green|+5%}}
|-
| [[File:Resolution technological sanctions.png|24px]] Minor Research Sanctions
| {{red|-5%}}
|-
| [[File:Resolution technological sanctions.png|24px]] Moderate Research Sanctions
| {{red|-10%}}
|-
| [[File:Resolution technological sanctions.png|24px]] Major Research Sanctions
| {{red|-15%}}
|}

== Technology cost ==
{{SVersion|2.8}}
As a game progresses, research option choices will begin to include progressively more advanced and correspondingly more expensive technologies.

Each technology has a ''base cost'' that applies as long as an empire does not exceed its Administrative Capacity. Once that happens, the research cost will be increased by {{red|0.3%}} for each point of exceeded Administrative Capacity.

This means that while overall an empire's research capabilities will increase with additional planets and systems, it will do so with increasingly diminishing returns for every new addition; Meaning, a larger empire will have to invest more resources than a smaller one to gain the same tech. This allows for empires of a somewhat differing size to keep a "relative" technological parity.

== Research progress ==
{{SVersion|2.8}}
In general, ''research time'' can be summarized as the following formula:

<math>\text{Research time} = \sum\frac{\text{Research cost} -\, \text{Partial research done} }{ \text{Monthly research progress} }</math>

Research progress is one of the key elements affecting the time it takes to discover new technologies. It is formulated as follows:

<math>\text{Monthly research progress} = \text{Research resource produced}\, \cdot\, \sum\text{Research speed modifiers}\, +\, \text{min}[\text{Research resource stored},\text{Research resource produced}]</math>

While it is possible for the ''monthly research progress'' to remain constant during the course of researching a certain technology, it is more than likely to fluctuate - for better or for worse - due to consequences of various actions (such as exploration, empire development, expansion, etc.). This, in turn, may increase or decrease the total research time of a given tech.

; Example
The empire from the previous examples (same setup) has just finished debris analysis granting it {{green|+10%}} research progress in {{icon|Armored Torpedoes tech|21px}} Armored Torpedoes along with {{icon|eng|21px}} {{green|+1000}} Engineering research (stored research).

This setup will generate the following monthly research progress:

<math>\text{Monthly research progress} = 24\, \cdot\, (1\, +\, 0.05\, +\, 0.15)\, +\, \text{min}[1000, 24] = 52.8 </math>

Assuming no further changes will impact the above setup, the total research time of the tech would be:

<math>\text{Research time} = \frac{1862\, -\, 1862 \cdot\, 0.1 }{ 52.8 } = \text{31.74 months}</math>

'''Note:''' ''Partial research'' can refer to debris analysis, previous research, event rewards and etc.

== References ==
<references />

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[[Category:Technology]]
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