Load when scripting custom camera behavior (cutscenes, third-person follow, custom rotation), manipulating CFrame for placement/rotation, raycasting from the screen, or building a non-default player view. Client-only.

Quick Reference

The Camera: workspace.CurrentCamera: one per client. Set CameraType = Scriptable to disable defaults and take full control. Without it, defaults overwrite your CFrame every frame.

CameraType: Fixed, Attach/Watch/Track/Follow (subject-following), Custom (default), Scriptable (no default), Orbital (fixed Y, rotates around player). CameraSubject cannot be nil: setting it reverts.

Key properties: CFrame, CameraSubject, FieldOfView (deg), FieldOfViewMode (Vertical/Diagonal), NearPlaneZ, ViewportSize, HeadLocked, HeadScale, Focus.

CFrame essentials:

Operation	Luau
Position only	`CFrame.new(position)`
Look at target	`CFrame.lookAt(position, target, upVector)`
XYZ rotation	`CFrame.Angles(rx, ry, rz)`
Local to world	`cf * Vector3.new(0, 0, 10)`
Interpolate	`cf:Lerp(goal, alpha)`
Unit axes	`cf.LookVector`, `cf.RightVector`, `cf.UpVector`

Custom camera loop: always PreRender, never Heartbeat:

camera.CameraType = Enum.CameraType.Scriptable
RunService.PreRender:Connect(function(dt)
    local desired = CFrame.lookAt(head.Position - offset, head.Position)
    camera.CFrame = camera.CFrame:Lerp(desired, math.min(dt * 10, 1))
end)

Raycasting from camera: camera:ScreenPointToRay(mx, my) (accounts for GUI inset) vs camera:ViewportPointToRay(mx, my) (raw, NO inset). ScreenPointToRay returns a unit Ray (1 stud); multiply Direction by length for the actual raycast.

Pitfalls:

Client-only. Server sets silently dropped.
Without Scriptable, defaults overwrite your CFrame every frame.
PreRender for camera (visual sync). Heartbeat adds 1-frame lag. RenderStepped still works but is superseded by PreRender.
Camera.CFrame lacks VR head rotation; use GetRenderCFrame() for the true view.
SetRoll is outdated; apply roll via CFrame.Angles(0, 0, roll) on CFrame.
CameraSubject = nil reverts to previous.
CFrame.new(pos, lookAt) is legacy (back-compat only); use CFrame.lookAt(at, lookAt) for new code.
ScreenPointToRay ≠ ViewportPointToRay (GUI inset). Use ScreenPointToRay for mouse input.

See references/full.md for first/third-person recipes, cutscenes, screen shake, mouse-look, full API.

npx skills add tabooharmony/roblox-brain --skill roblox-camera