Skill v1.0.1

version: "1.0.1" name: godot-genre-shooter-fps description: "Expert blueprint for First-Person Shooters: fps_camera_look, fps_movement_logic, hitscan_weapon_query, weapon_bobbing_system, procedural recoil, and FPS NEVER rules. Shared TPS/cover theory links to godot-genre-shooter. Keywords: FPS, movement physics, weapon bobbing, camera sway, hitscan, viewmodel, air control."

MANDATORY script reads (start here)

1. fps_camera_look.gd — raw _input mouse look (yaw/pitch)
2. fps_movement_logic.gd — accel/friction/air control
3. hitscan_weapon_query.gd — space-state hitscan
4. weapon_bobbing_system.gd — viewmodel bob/sway

Also: procedural_recoil_handler.gd, hitscan_weapon_logic.gd, advanced_fps_controller.gd, weapon_state_machine.gd, frame_perfect_input.gd, bullet_decal_spawner.gd, weapon_spread_calc.gd, server_projectile_instance.gd, player_anim_bridge.gd, recoil_system.gd (pattern + bloom), aim_assist.gd (controller friction/magnetism). advanced_weapon_controller.gd is shared theory — keep FPS feel in the scripts above; genre routing for TPS → sibling skill.

Core Loop

Move/Look → Aim → Fire (hitscan) → Recoil recover → Acquire

NEVER Do (FPS)

Gunplay & registration

• NEVER hit-detect in _process — use _physics_process + intersect_ray.
• NEVER apply recoil only to the gun mesh — kick camera + bloom/spread.
• NEVER trust client damage — server authority + lag compensation.
• NEVER forget exclude / add_exception for the player RID.
• NEVER use == on float cooldowns — is_equal_approx.

Input & movement

• NEVER poll mouse in _physics_process — _input / _unhandled_input for look.
• NEVER accumulate look on a raw Transform3D — store yaw/pitch floats.
• NEVER multiply velocity by delta before move_and_slide().
• NEVER use Transform3D.looking_at for muzzle forward — use -transform.basis.z.

Polish

• NEVER single AudioStreamPlayer for gunfire — layer mechanical + shot + tail.
• NEVER leave decals forever — fade/pool (bullet_decal_spawner.gd).
• NEVER hardcode weapon stats — WeaponData Resources.
• NEVER use plain Strings for hot weapon states — StringName.

Advanced FPS (keep)

Viewmodel sway / bob

Procedural sine bob + look sway — weapon_bobbing_system.gd.

Step-up

Ray forward/down from step_height when is_on_wall() after move_and_slide(); lift to step top for stairs.

Tactical lean

Roll camera Z + local X offset from Input.get_axis("lean_left","lean_right") with lerp.

Shared weapon theory

Hitscan vs projectile, spray patterns, and net prediction details that are not FPS-rig specific → godot-genre-shooter + combat/multiplayer complements. Implement FPS fire path via hitscan_weapon_query.gd + procedural_recoil_handler.gd + recoil_system.gd.

MANDATORY for hitscan/projectile tradeoffs, three-layer recoil, aim assist, weapon balance matrices, and client prediction: fps-weapon-theory.md. Do NOT Load after MANDATORY script reads unless extending beyond bob/step/lean.

Reference

Progressive disclosure: open Official Documentation links only when researching a specific API; load Related Skills when routing to a peer domain — do not preload the whole lattice.

Official Documentation

• Ray-casting — PhysicsDirectSpaceState3D intersect_ray patterns for hitscan registration without Area3D ballistics.
• Physics introduction — collision layers/masks, layers for player exclude, and physics tick vs visual frame for gunplay.
• Using 3D transforms — basis axes and -transform.basis.z forward vectors for aim, recoil, and muzzle direction.
• Using InputEvent — _input vs _physics_process so mouse look stays zero-latency while movement stays physics-synced.
• Mouse and input coordinates — relative mouse motion, capture, and screen-center projection for aim rays.
• Controllers, gamepads, and joysticks — analog look axes and deadzones that aim-assist friction/magnetism build on.
• Using decals — Decal node projection for bullet impacts instead of Sprite3D/QuadMesh stickers.
• High-level multiplayer — RPC authority and fire-event patterns for server-validated hitscan without syncing every bullet.
• Using AnimationTree — blend/state machines for idle/aim/fire/reload without ! in expressions.
• Resources — WeaponData Resource stats (damage, recoil, spread) instead of hardcoded class constants.
• Audio streams — layered mechanical/shot/tail streams for gunfire weight.
• Optimization using Servers — RenderingServer RID paths for high-volume visual projectiles without SceneTree spam.

Related Skills

Prerequisites

• godot-project-foundations — scene tree, InputMap actions, and Resource import basics before FPS controllers and WeaponData wiring.
• godot-input-handling — mouse capture, action buffering, and look vs move split that frame-perfect fire and camera look depend on.
• godot-raycasting-queries — physics-synced ray/shape queries and exclude RIDs that hitscan registration builds on.

Complements

• godot-camera-systems — FOV punch, lean pivots, and shake stacks that compose with procedural recoil and weapon bob.
• godot-combat-system — duck-typed damage application and hit-zone multipliers shared with hitscan/projectile confirm paths.
• godot-audio-systems — bus routing and pooled one-shots for layered gunfire without a single shared AudioStreamPlayer.
• godot-multiplayer-networking — authoritative fire RPCs and unreliable movement transfer modes for competitive hit validation.
• godot-adapt-single-to-multiplayer — client prediction / server reconciliation shells before lag-compensated shot validation.
• godot-state-machine-advanced — StringName fire/reload/idle machines without stringly-typed weapon states.
• godot-animation-tree-mastery — AnimationTree parameters and blend spaces driven by local velocity bridges.
• godot-performance-optimization — pooling, Decal budgets, and RenderingServer RID density for bullet visuals and impacts.
• godot-genre-shooter — broader TPS/hybrid shooter architecture when the project is not FPS-first.

Downstream / consumers

• godot-monte-carlo-balancer — simulate weapon asymmetry matrices, TTK bands, and bloom/recoil knobs before shipping balance tables.
• godot-genre-battle-royale — large-scale relevancy and lag-compensated combat that reuses FPS hitscan/recoil feel inside BR matches.

Master

• godot-master — library router and mirrored module entry; open when discovering which Domain Skill owns a cross-cutting FPS concern.