Bug Reporting for Games With Climbing Systems

Climbing systems let the player move along surfaces the rest of the movement code treats as walls, and they do it by continuously reading geometry: which faces are grippable, where the edges and handholds are, and when to transition to a mantle or back to walking. The bugs are about those reads and transitions. A player reporting that they could not grab a ledge, got stuck on a wall, or warped when mantling is describing a surface detection or grip transition that went wrong. This post is about capturing the climb surface and grip state that makes these bugs reproducible.

Climbing is continuous surface detection

A climbing system is constantly asking the world questions: is this surface climbable, where can the hands grip, where is the nearest edge, is there room to mantle over the top. It answers with probes and traces, then drives the character along the surface and through transitions. The bugs come from wrong answers and bad transitions. A ledge that will not grab usually means the detection did not classify it as grippable, or the grab reach fell just short. A character stuck on a wall is usually in a grip state with no valid move available.

Players cannot see the detection. They jumped at a ledge that looks obviously climbable and bounced off, or pressed toward a handhold the system did not register. The grippable classification, the detected handholds, and the reach checks are internal, and they depend on the exact position and angle the player approached from. Reproducing a climb bug means recreating that approach and the reads it produced, which a player can only describe as roughly here, on this wall, which is not enough to find it by hand.

Capturing climb surface state

Capture what the system detected about the surface: whether it classified the surface as climbable, the surface normal, the handholds or grip points it found, and the nearest edge or ledge. A failed ledge grab is usually explained the moment you see the surface was not classified as grippable there, perhaps because of a material tag, a normal outside the allowed range, or a gap in the handhold data on that section of geometry. The detection record is the system's read of the wall, and most climb bugs are that read being wrong.

Capture the raw probe results that produced the classification, not just the conclusion. Climbing geometry is frequently authored with separate climb volumes or tagged surfaces, and the bugs cluster where those volumes have gaps, overlaps, or seams against the visible mesh. When you can see the probe hit nothing grippable a few centimeters from where the player aimed, a maddening cannot-grab-this-ledge report becomes a clear authoring gap. Without the raw reads you are left trusting the conclusion, which is exactly the thing that was wrong.

Grip, reach, and hold state

While climbing, capture the grip state: which handholds the player is currently holding, the reach to the next available hold, and whether a reachable hold exists in the desired direction. A character stuck on a wall almost always shows a grip state where no hold is within reach in any direction the player is pressing, so the climb has nowhere to go. Seeing the available holds versus the player's input direction explains the stuck state precisely instead of leaving it as a vague hang.

Reach checks are a common failure point because they depend on the character's exact position, the hold positions, and the reach tolerance, all of which can be a touch off. A climb that feels like it should continue but will not is often a next hold just past the reach threshold, a few centimeters that feel like nothing to the player. Capturing the current holds, the candidate next holds, and the reach distances turns that into a measurement: the hold was reachable or it was not, and by how much. That number tells you whether to widen the reach or fix the hold placement.

Transitions: grab, mantle, and dismount

The transitions on and off climbing are where the dramatic bugs live, especially warps and stuck mantles. Capture the transition state: whether the player is grabbing, climbing, mantling, or dismounting, and the target position and animation for the transition. A mantle that warped the player to the wrong spot usually shows a target position computed from a bad edge read or a mismatched animation that assumed a different ledge height. The transition record names which transition fired and where it was trying to send the player.

Mantling in particular computes a destination on top of the ledge and plays an animation to get there, and if the destination or the space check is wrong, the player clips, floats, or warps. Capture the edge height used, the destination, and the clearance check above the ledge. A warp into geometry is legible once you see the destination was inside a wall or the clearance check passed when it should not have. These transition fields let you reproduce the exact mantle the player attempted rather than hunting for the one ledge in the level that triggers it.

Setting it up with Bugnet

Bugnet's in-game report button captures game state automatically, which is what climbing bugs require. When a player reports a failed grab, a stuck climb, or a warp, you attach the detected climb surface and its grippable classification, the raw probe results, the current and candidate handholds with reach distances, the transition state, and the mantle destination as custom fields. The player describes the wall in a sentence while Bugnet records the detection and grip state that explains it, so a bug tied to one ledge in one level does not depend on the player relaying coordinates.

Occurrence grouping folds repeated climb bugs at the same spot into one issue with a count, so a stretch of geometry that traps many players rises above scattered one-offs. Filter by custom fields like surface type, transition, or level area to isolate the pattern fast, and crashes during a climb transition arrive with stack traces and device context. The surface reads, the grip states, the transitions, the duplicates, and the crashes all live in one dashboard you can prioritize by how many players hit each ledge.

Building a climbing system you can audit

The durable practice is to make the climb system's reads and grip state inspectable. Keep the detected surface, raw probes, current and candidate holds, and the active transition queryable so any climb report carries the full picture of what the system saw and decided. Log grab and mantle transitions with their computed destinations so warps are auditable. None of this changes how climbing feels, but all of it turns a location-specific glitch into data pointing at the surface or transition that misbehaved.

Climbing bugs cluster around specific geometry and specific approach angles, which makes them very fixable once you can see the reads. Capture climb and transition state early, and your level and gameplay teams can fix bad climb spots against real reported reads instead of climbing every wall hoping to feel the glitch. Build the capture now, and your climbing will feel dependable and fluid rather than like a system that occasionally refuses an obvious ledge or flings the player into a wall.

Climbing bugs are surface and transition bugs. Capture the detected surface, the grip and reach, and the mantle destination and a refused ledge becomes reproducible.