WORK-IN-PROGRESS PREVIEW · 01 / INSIDE THE SHOT
Where does the
speed go?
A shot leaves the launcher. Follow how the program changes its speed, from a CPU instruction to the flight it produces.
Choose a recorded input, predict, and replay real LLDB evidence. New debugger experiments and the editable trace script run locally on an Apple Silicon Mac with Xcode command-line tools and LLDB. Teaching calibration and physical-phone acceptance are still pending. Learning guide.
YOUR EXPERIMENT
Case 01First, make a prediction.
At zero wind, does a faster launch change how strongly the shot slows down?
THE PROGRAM, MADE VISIBLE
An input becomes a movement.
Launching, pausing at the calculation, and capturing the instructions and values.
See the connection, one step at a time.
Make a prediction on the left, then run the shot. You'll inspect the actual values that pass through the compiled program.
Meet LLDB, the debugger. It pauses a running program so you can ask: which instruction changed this value? We’ll keep its original evidence beside the explanation.
1. An instruction changes a value
See the original instructions & register values
Register names are storage locations inside the CPU. The compiler reuses them. Only the measured entry values labeled below are treated as inputs.
2. That value changes the movement
First 0.02 secondsThe instruction snapshot is the first update. The flight cursor can inspect later positions.
How do we know this is the program's result?
The path is returned by the native executable. The animation only displays those coordinates; it does not calculate a replacement flight.
KEEP WHAT YOU LEARN
Your investigation notebook.
Cite a value or instruction. Say what it rules out, and what you would test next.
MAKE THE TOOL YOURSTake the trace script with you.
This Python script drives the real local investigation tool. Read it, change the input, and save your version. The page downloads your text; it does not execute edited code.
Loading the supplied script…