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Common Test Properties
Distance
Dot
Gameplay Tags
Overlap
Pathfinding
Pathfinding Batch
Project
Trace
Within the Environmental Query System (EQS), aTestcan be performed to determine whichItemproduced from a Generatoris the "best" option, given the Context(or frame of reference). Several Tests are provided with the Engine that covers a good percentage of use cases, such as "can an Item trace (see) another Location" or "is the distance between and Item and its Context within a specified range".You can add multiple Tests to a Generator which can be an effective way to narrow down the results, giving you the best possible option.
If the defaultEngine Tests do not accomplish what you desire, you can create custom Tests through C++ code.
Common Test Properties
Each Test type has some unique properties to it that enables you to define how the Test is performed. However, for all Tests, some common properties are used to define what the purpose of the Test is and what to do with the results. For example, is the Test used for filtering out results, oris it being used to score results and weight them, or a combination of both? You can define theTest Purposeamong other properties from theDetailspanel when selecting the Test in the EQS Editor.
Test Properties
Property | Description | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Test Comment | Optional comment or explanation about what the Test is used for. This is useful when the purpose of the Test may not be clear, especially when there are multiple Tests of the same type. | ||||||||
Test Purpose | This defines what additional options are available in the Test and what the test should be used for.
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Filter Properties
The following options are available whenTest Purposeis set toFilter(or set toFilter and Score):
Filtering is done before scoring to avoid calculating thescore on filtered-out items.
Property | Description |
|---|---|
Bool Match | This is the value (true or false)to match to grant a scoring factor. When performing a Test, not matching this value will not change the score. For example, on a TraceTest, true or false did we hit something? Or forPathingdoes a path exist? |
Multiple Context Filter Op | Defines the filtering operator when theDistance ToContext returns multiple items.All Passmeans all Contexts must pass whileAny Passstates at least one Context must pass. |
Float Value Min | Filter any value less than or equal to this value. This option is only available forDistanceandDotTests. |
Float Value Max | Filter any value greater than or equal to this value. This option is only available forDistanceandDotTests. |
Filter Type | Used to change the type of Filter applied toMinimum,Maximum, or aRangeof values. Any values outside the values specified in theFloat Value Min and/orFloat Value Max properties will be culled out. This option is only available forDistanceandDotTests. |
Score Properties
The following options are available whenTest Purposeis set toScore(or set toFilter and Score).
Property | Description |
|---|---|
Multiple Context Filter Op | Defines the filtering operator when theDistance ToContext returns multiple items.All Passmeans all Contexts must pass whileAny Passstates at least one Context must pass. |
ClampMin Type | Defines whether aSpecified Valueshould be used to normalize the raw test value before applying the scoring formula, or if thelowestvalue found (Tested) should be used. This option is only available forDistanceandDotTests. |
Clamp Max Type | Defines whetheraSpecified Valueshould be used to normalize the raw test value before applying the scoring formula, or if the highestvalue found (Tested) should be used. This option is only available forDistanceandDotTests. |
Scoring Equation | This modifies the score of the Test to adhere to a curve of theConstant,Linear,Square,Inverse Linear, orSquare Roottype. This option is only available forDistanceandDotTests. |
Scoring Factor | The weight (factor) in which to multiply the normalized score after the scoring equation is applied. This value can be a negative number. This option is only available forDistanceandDotTests. |
Normalization Type | Specifies how to determine the value span used to normalize score.Absolute(use 0 as the base of normalization range) orRelative to Scores(use the lowest Item score as the base of normalization range). This option is only available forDistanceandDotTests. |
Reference Value | Used to normalize Test's results in such a way that the closer a value is to Reference Value the higher normalized result it will produce. The value farthest away fromReference Value will be normalized to 0, and all other values in between will get normalized linearly with the distance toReference Value. This option is only available forDistanceandDotTests. |
Distance
TheDistanceTest will return the direct distance between the Item and the chosenDistance Toproperty. If Distance To is more than one location, it averages the results of each distance check.
Property | Description |
|---|---|
Test Mode | Themethod used to test Distance: in3D space, in 2D as an XY plane, along theZ or Z (absolute) axis. |
Distance To | The Context that will be used to measure the distanceto. |
Dot
TheDotTest calculates the Dot Product of two vectors. These can be Context rotations or vector from one point to another. This Test is useful for determining if something is facing something else.
The following properties are available for theDotTest:
Property | Description | ||||||
|---|---|---|---|---|---|---|---|
Line A Mode | This is used to define the direction of the first line used by the Test. There are two methods you use toobtain the direction:
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Line B Mode | This is used to define the direction of the secondline used by the Test. There are two methods you can use to obtain the direction:
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Test Mode | Whether the Test should calculate using the complete 3D vector or just the 2D heading vector of theLine AandLine Bvectors. | ||||||
Absolute Value | This will make the Test return the Absolute Value of the Dot Product (a Dot Product returns a value from -1.0 to 1.0). |
TheGameplay TagsTest enables you to specify a Tag to query and attempt to match in your Test.
Property | Description |
|---|---|
Tag Query to Match | Opens the Gameplay Tags Editor where you can specify the Tags to validate against. |
Reject Incompatible Items | Controls how to treat actors that do not implement IGamePlayTgAssetInterface. If true, actors that do not implement the interface will be ignored, meaning they will not be scored and will not be considered when filtering. If false, actors that do not implement the interface will be included in filter and score operations with a zero score. |
Overlap
TheOverlapTest can be used to determine if an Item (or Items) are within the bounds defined in the properties.
Property | Description |
|---|---|
Extent X | Shape parameter for the overlap along the X-axis. |
Extent Y | Shape parameter for the overlap along the Y-axis. |
Extent Z | Shape parameter for the overlap along the Z-axis. |
Shape Offset | Offset from the Item location at which to test the overlap. For example, you may need to offset vertically to avoid overlaps with flat ground. |
Overlap Channel | Geometry trace channel used for overlap. |
Overlap Shape | The shape used for geometry overlap (Box,Sphere, orCapsule). |
Only Blocking Hits | if set, overlap will only look for blocking hits. |
Overlap Complex | If set, overlap will only run on complex collisions. |
Skip Overlap Querier | If set, overlap will skip querier context hits. |
Pathfinding
ThePathfindingTest can be used to determine if a path exists to (orfrom) the Context, how expensive the path to (or from) the Context is, or how long the path is.
Property | Description | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Test Mode | The method in which to apply the Test:
| ||||||||
Context | This is the Context of the path to or from. | ||||||||
Path from Context | Should the pathfinder go to (false) or from (true) the Context. | ||||||||
Filter Class | The optional navigation filter to use in pathfinding. | ||||||||
Skip Unreachable | If set, Items with failed paths will be invalidated. |
WhenTest Modeis set toPath CostorPath Length, theFilterandScoresections of theDetailspanel change to provide the options typically only available to the common properties outlined forDotandDistancetests.
Pathfinding Batch
ThePathfindingTest can be used to determine if a path exists to (orfrom) the Context, how expensive the path to (or from) the Context is, or how long the path is.Every processed Context (paths) will be scored depending on the definedTest Mode.
Property | Description | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Test Mode | The method in which to apply the Test:
| ||||||||
Context | This is the Context that the AI should path to or from. | ||||||||
Path from Context | Should the pathfinder go to (false) or from (true) the Context. | ||||||||
Filter Class | The optional navigation filter to use in pathfinding. | ||||||||
Scan Range Multiplier | The multiplier for the max distance between point and Context. | ||||||||
Skip Unreachable | If set, Items with failed paths will be invalidated. |
WhenTest Modeis set toPath CostorPath Length, theFilterandScoresections of theDetailspanel change to provide the options typically only available to the common properties outlined forDotandDistancetests.
Project
The ProjectTest can be used to project theresulting Items onto the NavMesh (and which NavMesh data set to use).
This will move Items that may be inside walls or blocked, back onto the NavMesh, which can create bunching if a grid line happens to be just beyond the edge of the NavMesh.
Property | Description | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Trace Mode | This is the shape used for geometry tracing:
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Navigation Filter | The (optional)navigation filterclass to used. | ||||||||
Extent X | Shape parameter for trace. | ||||||||
Project Down | Search height is defined below the specified point. | ||||||||
Project Up | Search Height is defined above the specified point. | ||||||||
Post Projection Vertical Offset | This value will be added to the resulting location's Z-axis. This can be useful when projecting points onnavigation since the Navmesh is just an approximation of Level geometry and items may end up being under collide-able geometry which would, for example, falsify visibility tests. |
Trace
TheTraceTest will traceto (or from) an Item orContext and return if it hit it or not something. You can invert the result using theFilteroption,Bool Match. One typical use-case for this type of test is to determine if an enemy can (or cannot) see a Player in the Level.
Property | Description | ||||||
|---|---|---|---|---|---|---|---|
Trace Mode | This is the shape used for geometry tracing:
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Trace Channel | This is the channel to perform the trace against. By default,VisibilityandCameraare the available options however, additional channels can be added in theEdit Menu > Project Settings > Physics > Trace Channelssection of the Project Settings. | ||||||
Trace Shape | The shape to perform the trace:Line,Sphere,Box,orCapsule. | ||||||
Trace Complex | Whether the trace should be against the mesh (complex) or just the simple collision. | ||||||
Only Blocking Hits | Whether the trace uses blocking or non-blocking traces in its results. | ||||||
Trace from Context | The Context to trace from, such as the Querier, an Item, or any custom Contexts you may have created. | ||||||
Context | This is the other end of the trace. | ||||||
Item Height Offset | This will add a Z offset, in cm, to the Item the Test is tracing to (orfrom). | ||||||
Context Height Offset | This will add a Z offset, in cm, to the Context the test is tracing to (orfrom). |