Simulating a Roller Coaster

I was the author of Coaster! the screen saver, way back in 1993. This video is a warm up to restart the project.

I used original roller coaster design drawings, extracted a plan (top view) and an elevation (profile) and typed it all into files. then I wrote some software to read this data and create the coaster geometry. The code I wrote would go ahead every 10 feet thru the data and create track segments and a trestle, cross braces in 3D.

A second piece of code read these files, and created the camera motion along the track. That code understands the chain or lift portion of the ride, and then goes to gravity mode. The major portion of the ride is camera in gravity.
(My later versions accounted for roll, bank)
I used Euler integration for acceleration, (track (sin)slope * gravity) and it approximates the ride well.