This function returns a description of a volume that contains all BasePart children within a Model. The volume's orientation is based on the orientation of the PrimaryPart, and matches the selection box rendered in Studio when the model is selected. Mirroring the behavior of Terrain:FillBlock(), it returns a CFrame representing the center of that bounding box and a Vector3 representing its size.

If there is no PrimaryPart for the model, the bounding box will be aligned to the world axes.

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local model = workspace.Model
local part = workspace.Part
local orientation, size = model:GetBoundingBox()

-- Resize and position part equal to bounding box of model
part.Size = size
part.CFrame = orientation

Returns the size of the smallest bounding box that contains all of the BaseParts in the Model. If Model.PrimaryPart exists then the bounding box will be aligned to that part. If a primary part has not been set then the function will chose a part in the model to align the bounding box to. As the selection of this part is not deterministic it is recommended to set a Model.PrimaryPart to get consistent results with this function.

Note this function only returns the size of the smallest bounding box, and the developer must employ their own method to obtain the position of the bounding box.

When this method is called from a Script, it returns all the Player objects that this model is persistent for. When called from a LocalScript, this method only checks if this model is persistent for the LocalPlayer.

Models contain a persistent canonical scale factor, which starts out at 1 for newly created models and changes as the model is scaled by calling Model/ScaleTo. This function returns the current canonical scale factor of the model.

The current scale factor does not directly impact the size of Instances under the model. It is used for content authoring and scripting purposes to remember how the model has been scaled relative to its original size.

Within a given session, the model will cache the precise original size information of the descendant Instances after the first Model/ScaleTo call. This means that calling ScaleTo(x) followed by ScaleTo(1) will get you back exactly the original configuration of the model with no floating point drift. Avoiding floating point drift is the motivation for having a ScaleTo function instead of a ScaleBy function.

The scale factor does impact engine behavior in one way: The scale factor of a model will be applied to joint offsets of animations played on an AnimationController under that model, so that animated rigs will correctly play back animations even when scaled.

Controls how Models are streamed in and out when instance streaming is enabled. Behavior depends on the selected enum. Has no effect when streaming is not enabled.

This property should only be changed in Studio via the Properties window when streaming is enabled, or in Scripts, but never in LocalScripts (doing so can result in undefined behavior).

Moves the PrimaryPart to the given position. If a primary part has not been specified, the root part of the model will be used, but the root part is not deterministic and it is recommended that you always set a primary part when using MoveTo().

If there are any obstructions where the model is to be moved, such as Terrain or other BaseParts, the model will be moved vertically upward until there is nothing in the way. If this behavior is not desired, PVInstance:PivotTo() should be used instead.

Note that rotation is not preserved when moving a model with MoveTo(). It is recommended to use either TranslateBy() or PVInstance:PivotTo() if the current rotation of the model needs to be preserved.

Points to the primary part of the Model. The primary part is the BasePart that acts as the physical reference for the pivot of the model. That is, when parts within the model are moved due to physical simulation or other means, the pivot will move in sync with the primary part.

Note that Models do not have PrimaryPart set by default. If you are creating a model that needs to be acted upon by physics, you should manually set this property in Studio or within a script. If the primary part is not set, the pivot will remain at the same location in world space, even if parts within the model are moved.

Also note that when setting this property, it must be a BasePart that is a descendant of the model. If you try to set Model.PrimaryPart to a BasePart that is not a descendant of the model, it will be set to that part but reset to nil during the next simulation step — this is legacy behavior to support scripts which assume they can temporarily set the primary part to a BasePart which isn't a descendant of the model.

The general rule for models is that:

• Models whose parts are joined together via physical joints such as WeldConstraints or Motor6Ds should have a primary part assigned. For example, Roblox character models have their Model.PrimaryPart set to the HumanoidRootPart by default.
• Static (usually Anchored) models which stay in one place unless a script explicitly moves them don't require a Model.PrimaryPart and tend not to benefit from having one set.

Models contain a persistent canonical scale factor, which starts out at 1 for newly created models. This function scales the model, around the pivot location, relative to how it would look at a scale factor of 1. To accomplish this it does two things:

• Sets the current scale factor of the model to the specified value
• Resizes and repositions all descendant Instances accordingly

The scaling of locations is done around the pivot location.

All "geometric" properties of descendant Instances will be scaled. That obviously includes the sizes of parts, but here are some other examples of properties which are scaled:

• The length of joints like WeldConstraints, and Ropes
• Physical velocities and forces like Hinge.MaxServoTorque
• Visual properties like sizes of particle emitters
• Other length properties like Sound.RollOffMinDistance

Shifts a Model by the given Vector3 offset, preserving the model's orientation. If another BasePart or Terrain already exists at the new position then the Model will overlap said object.

The translation is applied in world space rather than object space, meaning even if the model's parts are orientated differently it will still move along the standard axis.

This property determines where the pivot of a Model which does not have a set Model.PrimaryPart is located. If the Model does have a PrimaryPart, the pivot of the Model is equal to the pivot of that primary part instead, and this WorldPivot property is ignored.

For a newly created Model, its pivot will be treated as the center of the bounding box of its contents until the first time its Model.WorldPivot property is set. Once the world pivot is set for the first time, it is impossible to restore this initial behavior.

Most commonly, moving the model with the Studio tools, or with model movement functions such as PVInstance:PivotTo() and Model:MoveTo(), will set the world pivot and thus end this new model behavior.

The purpose of this behavior is to allow Lua code to get a sensible pivot simply by creating a new model and parenting objects to it, avoiding the need to explicitly set Model.WorldPivot every time you create a model in code.

local model = Instance.new("Model")
workspace.BluePart.Parent = model
workspace.RedPart.Parent = model
model.Parent = workspace

print(model:GetPivot())  -- Currently equal to the center of the bounding box containing "BluePart" and "RedPart"

model:PivotTo(CFrame.new(0, 10, 0))  -- This works without needing to explicitly set "model.WorldPivot"