Coasters: Immersion

Riders

• Riders now react physically to the ride: arms drift up in airtime, head leans out through turns, body pitches under braking and acceleration
• On a real drop riders throw their arms above their head and hold them there — some do, some don't, each with their own threshold, speed and hold time, all derived from their identity so every client sees the same person behave the same way
• A seated rider's torso now faces the seat instead of twisting towards wherever you look; the head still turns, within a neck's range
• You sit facing the direction you were looking when you got on
• Optional anchored head, so you can orbit the third-person camera and actually watch the animations
• The model's head can follow the camera's pitch

Feel

• Your body now floats against the harness in airtime and sinks into the seat under g-force, measured along the seat's axes so it works upside down
• Separate control for how far you hang from the restraints while inverted
• Curve rounding smooths the corners between track segments without delaying steady curves
• Camera rattle now grows with the square of speed, and wind gusts instead of droning
• Launch punch rebuilt around longitudinal g plus actual speed gain: it fires on launches, and no longer on drops, chain lifts, or with the game paused
• Banking now comes from residual lateral g instead of the theoretical bank angle, so it no longer doubles up on tracks that are already banked
• Stabilisation now eases the horizon level instead of correcting instantly, which was adding motion through valleys rather than removing it
• Head inertia gains progressive damping and cuts its anticipation the moment you overshoot, removing the jolt when a curve straightens out
• Head inertia can now be turned off entirely

Performance

• Cart motion is interpolated with continuous velocity, removing the 50 ms hitch, with symmetric smoothing that also clears the ripple a chain lift leaves behind
• Sub-level render distance, in chunks
• Optional occlusion culling for sub-levels hidden behind terrain
• Track lookup no longer scans over a million block positions per second
• Track curve cache no longer thrashes when more than one drive is placed

Fixes

• Tracks and cogs no longer render translucent under shader packs
• Circuit drives only affect carts on their own track, and reconstruct the whole track rather than one segment
• Motorised bearing renders correctly when placed sideways
• Fixed a crash when leaving the world
• Fixed the first-person hand drifting off screen after dismounting

Menu

• Rewritten with its own widgets instead of vanilla's
• Presets: Recommended, Gentle, Balanced, Intense — everything else behind an advanced toggle
• The preset reads back as Custom the moment you change anything, and updates every slider live when you pick one
• A button in Sodium's options opens the full menu
• Every tooltip rewritten to describe what the option does, nothing else