What causes a laser puzzle beam not reflecting off a mirror?

The beam march stops when it hits any non-empty cell instead of transforming its direction when the cell is a mirror, so beams never bounce.

How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix a Laser Puzzle Beam Not Reflecting Off a Mirror

Quick answer: March the beam one cell at a time; when it enters a mirror cell, replace its direction with the reflected direction based on the mirror's orientation and continue marching.

A laser puzzle works by bouncing a beam off angled mirrors to a target. If your beam just halts at the first mirror, the march treats mirrors as walls. Reflect the direction and keep going.

How to fix it

1. March the beam cell by cell

Step the beam in its current direction one grid cell at a time, recording each cell it passes through for rendering. Stop at walls, the target, or the board edge.

2. Reflect on mirror cells

When the beam enters a mirror, map its incoming direction to the outgoing one. A / mirror swaps up<->right and down<->left; a \ mirror swaps up<->left and down<->right.

3. Detect the win and loops

If the beam reaches the target cell, the puzzle is solved. Cap the number of steps to avoid infinite loops when mirrors form a cycle.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every Pygame error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.

Most of the time the fix is small. Seeing the failure clearly is the part that actually costs you.