Retail's CTransition::find_transitional_position (:273613) has no step
cap. calc_num_steps (:272149) has a dedicated viewer branch `if ((state
& 4) != 0)` at :272181 for sight/viewer objects (ObjectInfoState.IsViewer
= 0x4). The existing acdream cap correctly had a comment "Sight objects
bypass this" but the bypass was never wired — no IsViewer caller existed
until the A8.F camera spring-arm.
With radius 0.3 m the cap fires at ~9 m. The spring-arm sweeps up to
40 m (≈134 steps), so zoomed-out cameras snapped to the player's head
instead of sweeping through geometry. The fix adds `&& !ObjectInfo.IsViewer`
to the guard; non-viewers keep the 30-step safety net (player spheres
~0.48 m radius never exceed 14 m/tick).
Conformance test: radius=0.3, dist=12 (40 steps > 30 cap) over flat
terrain. Normal mover bails (Assert.False). Viewer proceeds to target
(Assert.True + CurPos.X > from.X). RED → GREEN.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Port FindTransitionalPosition, TransitionalInsert, FindEnvCollisions,
AdjustOffset, DoStepDown, ValidateTransition from transition_pseudocode.md.
Outdoor terrain collision with step-down ground contact. Indoor BSP and
object collision deferred to subsequent tasks.
Also adds PhysicsEngine.SampleTerrainZ() which dispatches the terrain Z
query to the right registered landblock by world-space XY position.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
