Cylinder frame: scene calculation and near hemisphere

Module cylinderFrameTruth.ts. It defines two critical pieces for consistency between:

• visualizacion en 3D del cilindro (cilindro/cilindro-texturas)
• 3D editor (discs, ellipses, selection, and editing)

The goal is to use the same depth and the same visible hemisphere across the entire Hub app.

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1. Problem it solves

When UI calculates:

• where cylinder center is in world space (for meshes and editing)
• which texture portion belongs to near/visible hemisphere (for UV cropping/selection)

it is easy for different components to use different conventions.

cylinderFrameTruth.ts unifies those conventions:

• getCylinderFrameAtCaptureCenter(...) -> frame del cilindro en el centro de captura
• getNearHemisphereBoundsFromBOHs(...) -> bounds { uMin, uMax } del hemisferio cercano

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2. getCylinderFrameAtCaptureCenter(...)

Signature (current implementation):

• plane: GeologicalPlane
• measurement: { device_info?, compositeImageDepth?, boh_lines? } | null | undefined
• trajectory: TrajectoryPoint[]
• offset: {x,y,z} (offset del contexto de escena)
• profile: HUB_CYLINDER_DISPLAY_PROFILE.trajectory | HUB_CYLINDER_DISPLAY_PROFILE.editor3d
• fallbacks?: LiveMeasurementDepthFallbacks

What it does:

1. Determines geometry by plane diameter:
   • diameterType = plane.cylinderDiameter ?? 'H'
   • dims = getCylinderDimensions(diameterType)
   • radiusM y heightM salen de dims
2. Calculates targetDepthM using depth truth module:
   • getCylinderTrajectoryAnchorDepthM(plane, heightM, fallbacks)
3. Calculates base world position/orientation:
   • calculateImagePositionOnTrajectory(targetDepthM, trajectory, offset, heightM)
4. Canonicalizes BOH angles:
   • getCanonicalBohAnglesFromPlane(plane, measurement)
5. Builds final quaternion:
   • calculateImageOrientation(axisDirWorld, line1Angle, line2Angle, profile.imageOrientationAxialDeg, result.azimuthAtDepth)

CylinderFrame output:

• centerWorld: THREE.Vector3
• axisDirWorld: THREE.Vector3
• quaternionWorld: THREE.Quaternion
• radiusM: number
• heightM: number
• targetDepthM: number

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3. getNearHemisphereBoundsFromBOHs(...)

Input:

• boh1AngleDeg
• boh2AngleDeg
• bohLocalOffsetDeg

Output:

• { uMin, uMax } in canonical U space (0..1) with wrap handling.

Concept:

• BOH angles define a "front" and an interval around center (using angular offset from BOH_AXIAL_OFFSET_DEG + bohLocalOffsetDeg)
• Two points are computed (2D XY) and used to extract a local front vector
• It converts to U (atan2 + normalization)
• It builds a total 0.5-wide window (0.25 each side in U)

In practice:

• FieldCylinderWithData / FieldCaptureView3D / FullscreenCylinderEditor3D
• used to apply crops or bounds when selection/editing is restricted to near hemisphere

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4. Validation checklist

1. Select a measurement with visible BOHs:
   • verify uMin/uMax covers the same side as camera view
2. Edit discs/ellipses:
   • verify editing does not jump to far-side areas when it should not
3. Depth fallback cases:
   • when captureDepthCenter is missing, verify cylinder anchor stays stable across views