Documentation

DELIVERABLES

Deliverables — Cannon Drop

Summary

Cannon Drop is a 2D physics puzzle game built with TypeScript, HTML5 Canvas, and Matter.js. The player aims a cannon, fires a ball through a field of pegs and obstacles, and scores by clearing orange pegs and landing in buckets.

What Was Built

Engine Module (cannon-drop-engine.ts) — Pure TypeScript module with all game logic, level data (5 levels), scoring, combo multipliers, star ratings, aim/launch mechanics, and game state management. Zero browser dependencies. Fully testable with Node.js.
HTML Game (cannon-drop.html) — Browser file with Matter.js physics, 4-layer Canvas rendering (background, objects, ball/FX, UI), procedural audio via Web Audio API, mouse/keyboard input, level select screen, HUD, and level complete overlays.
Build Pipeline — TypeScript compilation via tsc with HTML copy to dist/.
Test Suite — 155 programmatic tests covering all engine functions, level data, scoring, and edge cases.

Test Results (from `node --test` output)

shell

# tests 155
# suites 49
# pass 155
# fail 0
# cancelled 0
# skipped 0

Feature Coverage

Implemented (Must-Have)

Requirement	Feature	Status
FR-1	Level Data System (5 levels, exact peg positions, bucket configs, obstacle counts)	Done
FR-2	Peg Base Values (orange=100, blue=25, green=500)	Done
FR-3	Combo Multiplier (tiered: 1/2/3/5/10)	Done
FR-4	Shot Score Calculation (delegates to getComboMultiplier)	Done
FR-5	Star Rating (0-3 stars, allPegsCleared override)	Done
FR-6	Aim and Launch (clampAngle, clampPower, calculateLaunchVelocity)	Done
FR-7	Game State Management (createGameState with getLevelData delegation)	Done
FR-8	Level Completion and Game Over	Done
FR-9	Slow-Motion Trigger	Done
FR-10	Ball Count and Green Peg Bonus	Done
FR-11	Physics World Setup (Matter.js engine, bodies, collision detection)	Done
FR-12	Peg Collision and Removal	Done
FR-13	Pivoting Platform Physics	Done
FR-14	Pipe and Chute Construction	Done
FR-15	Bumper Physics	Done
FR-16	Funnel Physics	Done
FR-17	Bucket Scoring Detection	Done
FR-18	Moving Jackpot Bucket (Level 5 only)	Done
FR-19	Wall Boundaries	Done
FR-20	Multi-Layer Canvas Rendering (4 visible + 1 offscreen bloom)	Done
FR-21	Ball Rendering and Effects (gradients, glow, particles)	Done
FR-22	Peg Rendering and Hit Animations	Done
FR-23	Obstacle Rendering (platforms, pipes, bumpers, funnels, buckets)	Done
FR-24	Background and Atmosphere (gradient, bokeh, vignette)	Done
FR-25	Bloom/Glow Post-Processing (offscreen canvas)	Done
FR-26	Screen Effects (shake, slow motion, confetti)	Done
FR-27	Level Select Screen (frosted glass cards, lock icons, stars)	Done
FR-28	In-Game HUD (score, balls, orange count, combo)	Done
FR-29	Level Complete Overlay (stars, score, continue)	Done
FR-30	Aiming Interface (cannon rotation, trajectory, power meter)	Done
FR-31	Input Handling (mouse aim/fire, R reset, N next level)	Done
FR-32	Responsive Canvas Sizing (5:4 aspect, letterboxing)	Done
FR-33	Procedural Sound Effects (fire, peg hit, bumper, bucket, ball lost, level complete, green peg)	Done
FR-34	Ambient Audio and Volume Control	Done
FR-35	TypeScript Build Pipeline (tsc + HTML copy)	Done

Nice-to-Have Features

Implemented

FR-21: Motion trail particles while ball is moving
FR-22: Score popups with spring animation and color-matching
FR-25: Bloom canvas (offscreen at half resolution)
FR-26: Confetti on level complete (150 particles, 3-5 seconds)

Deferred

FR-21: Full ribbon motion trail with additive blending — simplified to particle sparks for performance
FR-25: Multi-pass box blur — bloom canvas exists but blur passes simplified
FR-33: Pipe rolling sound — deferred (continuous brown noise modulation complex to implement without distortion)
FR-33: Slow-mo audio filter sweep — deferred (low-pass sweep on all audio requires re-routing all nodes)

Project Layout