Area Triggers
Virtual Effects
Unlike their non-Area versions, the effects of Area triggers are virtual - the effect is temporary and is undone when the trigger is stopped. Area effects are recalculated every game tick, 240 times per second.
Non-Area Move, Rotate and Scaling effects use the real position of the objects. However, triggers that target the position of an object will use the virtual position of the object. Triggers that use transformations (rotation or scaling) of an object as reference will use the virtual transform of the object.
Timings
Area triggers are processed once per tick after all other moves. The latest point at which you can call an Area trigger and still be processed within the same tick is from a Keyframe Spawn. Collisions happen after Area triggers are processed.
Move processing order: Keyframe 🡒 Scale 🡒 Rotate 🡒 Move 🡒 Advanced Follow Y 🡒 Advanced Follow 🡒 Follow 🡒 Area
EffectIDs
EffectIDs are unique per type of Area trigger; Spawning a new Area Move will overwrite any active Area Move with the same EffectID, but not other kinds of Area trigger like Area Scale, Rotate, etc. EffectID 0 is not unique - there is no limit to how many triggers you can spawn using this ID.
Center
Center Group ID must be a single object, or have an ID Parent. If present, the ID Parent is used as the center. Group and Area Parents have no effect on the center. If no valid center exists, the Area trigger uses the level’s origin (0,0) coordinate as the center, which is 3 block units below the editor guide axis. P1 and P2 positions, as well as camera positions (center, edges, corners) can be used as the center. Center Group ID can be identical to Target Group ID.
Order & Priority
Order
Area triggers are processed in the following order: Area Scale 🡒 Area Rotate 🡒 Area Move 🡒 Area Fade / Area Tint It is not possible to change this order with Priority.
Priority
Area triggers have cumulative effects - Priority decides the order in which they are applied, from highest first to lowest last. If there are multiple active triggers with the same Priority, then spawn order is used (oldest first to newest last).
Multiple Areas
When multiple Areas target the same objects, they are processed first by Priority, then from oldest to newest. Consecutive Area triggers use the position of center and target objects after the effect of the previous Area trigger is applied. Meaning that if you change the position of an object with an Area trigger, the next Area trigger will use the new positions as reference.
Multiple Instances
Normally, spawning the same Area trigger while an instance of it is already active updates the current active instance, it will not create new instances or override previous ones. Spawn order is unaffected by this. Edit Area effects will be stopped and undone. EffectID has no effect on this behavior. With spawn remapping, it is possible to create additional instances of the same Area trigger for unique sets of target, center and control IDs (only if control ID is not 0). The same target group can be affected by different centers and the same center can affect multiple different target groups. As a result, it is not possible to use an Area trigger multiple times on the same set of groups. Using EffectID to ensure only one instance of Area is active is unnecessary in most cases. Stopping the Area trigger before spawning is only necessary for refreshing active instances or changing order. Special centers like P1, P2, C, etc override the default Center Group ID - which can still be remapped, so it is possible to apply the same Area effect multiple times on the same group without needing to use multiple center groups if using a special center.
Spawn Remapping
Target Group ID and Center Group ID can be remapped. EffectID cannot be remapped. Color Channel (Area Tint) cannot be remapped. While EffectIDs are not remappable, ID 0 can be used to use the same Area trigger for multiple different groups. These instances can be stopped individually using a Control ID, but cannot be edited individually as only GroupIDs or EffectIDs can be used, which are not remappable.
Area Parents and Group Parents
If no Area Parents are present, the Group Parent acts as both Group Parent and Area Parent, and vice-versa. Group and Area Parents do not update dynamically, the choice is done at level start. With multiple Group Parents in the same link, the left-most, then bottom-most Group Parent is used. Likewise for Area Parents. The Group Parent is the center for the effect applied (Area Scale & Area Rotate). The Area Parent is the center used to calculate the distance from the Area trigger’s center. With DEAP selected, the Area Parent will not be affected by the Area trigger. Linked objects will still be affected. DEAP ignores Area Parents not part of linked objects or linked groups.
Object Linking
Object Linking
When linking multiple objects, they are treated as one object for the effects of Area triggers as long as an Area Parent or Group Parent is present. Linked objects do not have to be part of the target group, however Group / Area Parents not part of the target group are ignored. Ignore Linked ignores any Area Links present. The Area trigger’s effect is applied to all linked objects, even if they are not part of the target group.
ID Parent Linking
If an ID Parent is present, the entire group is treated as one object for the effects of Area triggers. If no Area Parents or Group Parents are present, the ID Parent acts as both Group Parent and Area Parent. If an Area Parent or Group Parent is present on an object that is not the ID Parent, it will act as both Area and Group Parent. If the ID Parent object is an Area/Group Parent, other Area/Group Parents in the same group are ignored.
Ignore GParent ignores the ID Parent. ID Parents override object links. Unlike object links, for group links the area effect is not applied to objects not part of the target group. If the affected object is an ID Parent for another group, then the effect is applied to the entire group. While object links need multiple objects to count as linked, you only need one ID Parent to create a linked group.
Visibility
An object counts as not visible if its center is outside of the screen’s edges by at least half a block. Objects can take up to ~0.1333 seconds to count as not visible in some cases.
Area Fade and Area Tint effects do not apply if the target is not visible. For Area Move, Scale and Rotate, if an object is not visible the effect will stop being applied in certain cases.
Link Visible can be used to force objects to be visible to fix any issues regarding visibility.
Performance and Optimization
Area triggers reapply their effect every tick, so they put a constant strain on the processor. Lag components can be split in two categories:
- Strength calculations for each target
- Effect application
Out of the two, applying area effects is the much more demanding one.
Enter triggers are far more optimized and should not be replaced by Area triggers.
Effect Strength
If the resulting effect strength is 0, no Area effect will be applied.
Certain proximity options will make the Area affect less (or more) targets depending on the strength calculation.
Object Links
Transformations (Scale, Rotate) and color operations (Fade, Tint) are applied per object even when using object links.
Scaling and rotation on object links also applies movement on all objects linked to the target, which is done per object. This makes Area Scale and Rotate the laggiest Area triggers when using object links.
Movements are optimized for multiple objects, using object links with Area Move can make use of this optimization and significantly reduce lag.
Overall, Area Move is the only Area trigger that sees a significant improvement from using object links. Area Fade and Tint have negligible increases from reducing the amount of targets that need to be calculated while Area Scale and Rotate are negatively impacted by it.
Fade and Tint
Area Fade and Tint effects are applied only on visible targets that are not toggled off. This includes completely transparent targets done using either the Hide object option, color blending, color opacity or Alpha triggers.
If there are multiple Area Fade triggers per target, all will do the strength calculation but only the strongest (or first) effect will be applied. This is not the case for other Area effects where all are applied.
Scale, Rotate and Move
Whether Area Scale, Rotate and Move is applied on toggled off targets is inconsistent and depends on length and deadzone settings. Toggling off targets has no effect in most common cases, so toggling shouldn’t be considered a reliable way to optimize these effects.
Effect Strength Coefficient
The effect of Area triggers varies depending on the distance between the center and targets. The strength coefficient represents the proportion of the applied effect for all Area triggers.
Distance
Distance is calculated between center and affected object then multiplied by ModFront / ModBack. Offset and OffsetY offset the position of the center after mod is applied. The distance value is sensible to float and addition errors - centering an object perfectly after it is moved is not always possible.
Distance can be calculated using these formulas:
c is position of center t is position of target
Circular Proximity
$Distance=\sqrt{(OffsetY+Y_{c}-Y_{t})^{2}+(Offset+X_{c}-X_{t})^{2}}$
Horizontal Proximity
$Distance=Offset+(X_{c}-X_{t})\cdot Mod$
Vertical Proximity
$Distance=Offset+(Y_{c}-Y_{t})\cdot Mod$
Mod
For radial proximity, Mod has no effect. For horizontal and vertical proximity, ModBack is applied if $CenterPos>TargetPos$ and ModFront is applied if $CenterPos<TargetPos$. For the symmetrical options, the value of Distance is always positive when ModFront is applied, even if the value of ModFront is negative. Offsets are not affected by mod.
Ease Out
With Ease Out enabled, Easing is applied on ModBack and Easing2 is applied on ModFront. Easing2 is mistakenly applied when using radial proximity, conflicting with Easing.
Length and Deadzone
Length and Deadzone determine the strength of the effect at different distances, from a min of 0 to a max of 1.
If Length is 0 or Deadzone is 1, then the value steps directly between max and min. Otherwise, the value follows a linear equation bounded between [1,0] using the formula:
$EffectStrength_{\ |⟹}=\frac{Distance-Length\cdot Deadzone}{Length\cdot(1-Deadzone)}$
$EffectStrength_{\ |⟹}=1-EffectStrength_{\ |⟸}$
The result is fed into the Easing function and is then used to calculate the strength of the effect applied.
Notations
- L = Length
- Dz = Deadzone
- Max - Distance value at max strength
- Min - Distance value at min strength
- Center - Strength value at distance 0
- Sign - The sign of distance (positive or negative) where the strength is greater than min
- Direction - The direction (relative to the center) along which the strength value decreases
Center ⟹ Edge
| Length | Deadzone | Max | Min | Center | Sign | Direction |
|---|---|---|---|---|---|---|
| $L \gt 0$ | $Dz \gt 1$ | $\ge Dz\cdot L$ | $\le L$ | 0 | + | |⟸ |
| $L \gt 0$ | $Dz = 1$ | $\lt L$ | $\ge L$ | 1 | + | |⟹ |
| $L \gt 0$ | $0\lt Dz\lt 1$ | $\le Dz\cdot L$ | $\ge L$ | 1 | + | |⟹ |
| $L \gt 0$ | $Dz = 0$ | $\le 0$ | $\ge L$ | 1 | + | |⟹ |
| $L \gt 0$ | $Dz \lt 0$ | $\le Dz\cdot L$ | $\ge L$ | $Dz/(Dz-1)$ | -/+ | |⟹ |
| $L = 0$ | $Dz \gt 1$ | $\gt 0$ | $\le 0$ | 0 | + | |⟸ |
| $L = 0$ | $Dz \le 1$ | $\lt 0$ | $\ge 0$ | 0 | - | |⟸ |
| $L \lt 0$ | $Dz \gt 1$ | $\le Dz\cdot L$ | $\ge L$ | 0 | - | |⟸ |
| $L \lt 0$ | $Dz = 1$ | $\gt L$ | $\le L$ | 1 | - | |⟹ |
| $L \lt 0$ | $0\lt Dz\lt 1$ | $\ge Dz\cdot L$ | $\le L$ | 1 | - | |⟹ |
| $L \lt 0$ | $Dz = 0$ | $\ge 0$ | $\le L$ | 1 | - | |⟹ |
| $L \lt 0$ | $Dz \lt 0$ | $\ge Dz\cdot L$ | $\le L$ | $Dz/(Dz-1)$ | -/+ | |⟸ |
Center ⟸ Edge
| Length | Deadzone | Max | Min | Center | Sign | Direction |
|---|---|---|---|---|---|---|
| $L \gt 0$ | $Dz \gt 1$ | $\le L$ | $\ge Dz\cdot L$ | 1 | + | |⟹ |
| $L \gt 0$ | $Dz = 1$ | $\ge L$ | $\lt L$ | 0 | + | |⟸ |
| $L \gt 0$ | $0\lt Dz\lt 1$ | $\ge L$ | $\le Dz\cdot L$ | 0 | + | |⟸ |
| $L \gt 0$ | $Dz = 0$ | $\ge L$ | $\le 0$ | 0 | + | |⟸ |
| $L \gt 0$ | $Dz \lt 0$ | $\ge L$ | $\le Dz\cdot L$ | $1/(1-Dz)$ | -/+ | |⟸ |
| $L = 0$ | $Dz \gt 1$ | $\le 0$ | $\gt 0$ | 1 | + | |⟹ |
| $L = 0$ | $Dz \le 1$ | $\ge 0$ | $\lt 0$ | 1 | - | |⟹ |
| $L \lt 0$ | $Dz \gt 1$ | $\ge L$ | $\le Dz\cdot L$ | 1 | - | |⟹ |
| $L \lt 0$ | $Dz = 1$ | $\le L$ | $\gt L$ | 0 | - | |⟸ |
| $L \lt 0$ | $0\lt Dz\lt 1$ | $\le L$ | $\ge Dz\cdot L$ | 0 | - | |⟸ |
| $L \lt 0$ | $Dz = 0$ | $\le L$ | $\ge 0$ | 1 | - | |⟸ |
| $L \lt 0$ | $Dz \lt 0$ | $\le L$ | $\ge Dz\cdot L$ | $1/(1-Dz)$ | -/+ | |⟹ |
Proximity Settings
| Image | No. | Area | Direction | ModBack | ModFront | Offset |
|---|---|---|---|---|---|---|
| 1 | Circular | |⟹ | No Effect | No Effect | X axis | |
| 2 | Circular | |⟸ | No Effect | No Effect | X axis | |
| 3 | Horizontal | |⟹ | Left | Right, Absolute | X axis | |
| 4 | Horizontal | |⟸ | Left | Right, Absolute | X axis | |
| 5 | Horizontal | |⟹ | Left | Right | X axis | |
| 6 | Horizontal | |⟸ | Left | Right | X axis | |
| 7 | Vertical | |⟹ | Down | Up, Absolute | Y axis | |
| 8 | Vertical | |⟸ | Down | Up, Absolute | Y axis | |
| 9 | Vertical | |⟸ | Down | Up | Y axis | |
| 10 | Vertical | |⟹ | Down | Up | Y axis |
Specific Settings & Behavior
Area Move
Unique Settings
- MoveDist
- MoveAngle
- Relative
- RFade
- XY Mode
- MoveX
- MoveY
Behavior
Moves the object by the distance specified by MoveDist (10 units = 1 block unit) in the direction given by MoveAngle. MoveAngle is defined in degrees (360 degrees = 1 rotation going counterclockwise) and the 0 degree point is down. With Relative enabled each object moves in the opposite direction of the center (angle between object and center, offset by 180°). Relative overrides MoveAngle. Angle is not affected by object rotation. Angle is not affected by ModFront / Modback. Center of angle is affected by Offset and OffsetY. MoveDist is multiplied by the distance between target and center and then divided by RFade if Relative is enabled. XY Mode replaces the angle and move settings with the cardinal movement settings MoveX and MoveY.
Equations
XY Movement
$X = XMove \cdot EffectStrength + X_{t}$ $Y = YMove \cdot EffectStrength + Y_{t}$
Relative Movement
$Distance=\sqrt{(VerticalOffset+Y_{c}-Y_{t})^{2}+(HorizontalOffset+X_{c}-X_{t})^{2}}$
$Radius = (3\cdot MoveDist) \cdot EffectStrength\cdot \min(\frac{Distance}{RFade},1)$
$Angle = \arctan(\frac{(Y_{c}-Y_{t}}{X_{c}-X_{t}})$
$X = Radius \cdot \cos(Angle) + X_{t}$ $Y = Radius \cdot \sin(Angle) + Y_{t}$
Where: c is position of center t is position of target $VerticalOffset$ is OffsetY for radial and Offset for vertical proximity. $HorizontalOffset$ is Offset for radial and horizontal proximity.
Area Rotate
Unique Settings
- Rotation
Rotation
Behavior
Rotates objects by a number of degrees given by Rotation (360 degrees = 1 rotation going clockwise). Move effects (except Area Move) are also rotated. The hitbox of solid objects is always in line with the coordinate system. While the visual rotates by any degree given, the hitbox can only rotate in increments of 90 degrees. If the rotation value is between 90 degree increments, then the hitbox is going to be sized up so the rotated object would fit inside.
Area Scale
Unique Settings
- ScaleX
- ScaleY
Behavior
If not linked, objects are scaled along their own XY axis. If linked, objects are scaled along the world XY axis. Area Scale does not support relative rotation.
The scale effect applied is calculated using this formula:
$EffectScale=1+EffectStrength \cdot (Scale-1)$
Where Scale is ScaleX or ScaleY.
If the scale value is negative, the object will be flipped around the respective axis. Due to a bug with Area Scale solid object hitboxes become thin when scaled with a negative value. Area Scale will not work if both X and Y scale are equal to 0. Objects can be scaled by 0 on one axis if the other axis is non-zero; To scale an object on both X and Y to 0 two Area Scale triggers are needed. Area Scale is considered a scaling effect by Scale trigger’s Relative Scale option.
The degree of slopes can be changed using transform effects like object warping or Area Scale. Move effects (except Area Move and Area Rotate) are also scaled.
Area Fade
Unique Settings
- From Opacity
- To Opacity
Behavior
From Opacity is the opacity at maximum strength, while To Opacity is the opacity at minimum. Unlike other Area triggers, Area Fade effects do not stack additively or multiplicatively with one another. When multiple Area Fade effects are applied on the same object, the one with the highest Effect Strength is applied regardless of the opacity value. If there is a tie, the first effect is used as determined by Priority and spawn order. The effect multiplies with other opacity effects (Alpha trigger and color channel Opacity). Area Fade does not have an Easing option. Due to a bug, Area Fade effects stop working for one frame after the game is unpaused.
Area Tint
Unique Settings
- Color Channel
- Tint
- HSV
- Main Only
- Secondary Only
Behavior
Area Tint is applied after other color effects (Color, Pulse, Copy Color).
The effect applied is calculated using this formula: $Color=ObjectColor+Tint(ColorChannel-ObjectColor)$ $ObjectColor \le Color \le ColorChannel$
For $Tint \le 0$ no tint is applied. For $0 \lt Tint \lt 1$ the max tint is proportional to Tint. For $Tint = 1$ at max tint the object color is equal to Color Channel. For $Tint \gt 1$ the strength of the tint applied is increased, but still maxes out at the color given by Color Channel.
Area Tint does not have an Easing option. With Main Only or Secondary Only selected, only the Base, respectively Detail Color will be tinted. Objects keep their blending and alpha values when tinted. Area Tint ignores the Base / Detail Color setting of single-color objects.
Random Values
Some variables can be randomized with the corresponding +/- option (the offset). For example, with a value of 5 +/- 1 a random value between 4 and 6 will be picked. The formula used is: $RandomValue=BaseValue+RandomCoefficient\cdot RandomOffset$
The random coefficient (a random value between +/-1) for each setting is calculated per object at level start.
Different triggers can have different base values and offsets, but they all share the same random coefficients since they are defined per object. While you can change the base value and offset of each setting, this will not randomize the values again. It is not possible to change random coefficients without restarting the level. With linked objects, the Group Parent’s random coefficients are used. Shared parameters, like Length, have the same random coefficient for all types of Area trigger. This also applies to OffsetY and Offset.