Theme and Art Direction

Creative north star

Solar noir at a dying signal station. The world is built from warm analog instruments and severe architectural shadows. Light is beautiful, useful, and dangerous. Darkness is quiet, protective, and temporary.

Every presentation decision should reinforce one of three ideas:

• sunlight carries power and information;
• exposure attracts mechanical attention;
• the player is reconstructing one final transmission.

Setting

Heliograph takes place inside a remote relay complex built to transmit messages through mirrors and coded flashes. The network has fallen silent. Its lenses are cracked, its cipher drums are incomplete, and autonomous Watchers still guard the illuminated routes.

The player is a small signal courier carrying a light cell. They cross the station, recover glyph mappings from exposed relay plates, and decode the last message before leaving the array.

Keep narrative delivery environmental and short. The jam build needs a title card, one opening line, room names, terminal text, and a final decoded message. It does not need dialogue scenes or lore collectibles.

Visual language

The style combines three source families without reproducing a specific historical machine:

Source	Shapes and materials	Use
Heliograph optics	Circular mirrors, shutters, tripods, hard beams	Sunlight zones, checkpoints, sentries
Cryptographic machinery	Rotors, punched marks, segmented labels, cable paths	Terminals, glyph panels, level decoration
Solar observatory	Stone arches, long windows, brass rails, dust	Environment silhouette and scale

Use large readable shapes. Fine mechanical detail belongs in backgrounds and terminal close-ups, not on collision-critical edges.

Palette

Token	Hex	Role
Ink	#0B1020	Deepest background and silhouette
Shadow	#18233A	Playable shadow space
Twilight	#4C3F72	Distant architecture and depth
Sun	#FFD166	Safe-to-read sunlight and charge
Heat	#FF8C42	Intense exposure and active machinery
Signal	#7BE0D6	Decoded information and checkpoint confirmation
Danger	#E84A5F	Sentry warning and lethal state
Paper	#F2E9D8	Text, glyph labels, and high-contrast UI

Sunlight should shift from Sun at the beam edge to Heat near its source. Shadow remains blue-violet rather than black so hazards and terrain are still readable.

Do not communicate state with hue alone:

• sunlight has drifting dust and a sharp diagonal edge;
• shadow has still air and low-contrast vertical texture;
• an active platform gains a solid outline and upward particles;
• sentry warning adds a pulse, sound, and expanding sight marker;
• depleted charge increases meter pulse frequency and player flicker.

Lighting grammar

Gameplay light uses authored Area2D zones. The artwork may soften beam edges, but the playable boundary must remain legible within roughly 8px.

State	Presentation
Enter sunlight	Gold rim light on player, cell brightens, warm layer fades in over 0.12s
Remain in sunlight	Dust travels along beam; charge meter fills steadily
Enter shadow	Rim light closes like a shutter; ambience becomes quieter
Low charge	Cell and HUD pulse below 25%; heartbeat/tick interval shortens
Light platform inactive	Faint engraved anchors remain visible; surface and collision are absent
Light platform active	Anchors connect into a solid gold-white surface

Inactive platform anchors are important. The player must be able to plan a route before exposing themselves.

Character language

The Courier

• Use the generated yellow Courier sheet normalized to anchored 64x64px runtime frames with nearest filtering.
• Keep the gameplay collider near 20x38px; transparent sprite padding and the helmet may extend beyond it.
• Bright circular light cell at the sternum or backpack.
• One trailing cable and cyan speed streaks communicate run and dash direction.
• No facial animation requirement; pose and cell state carry feedback.
• Sunlight adds a warm edge; shadow leaves only the cell and pale eye slit readable.

The Watcher

• Use the generated three-state optical machine at 96x96px: amber sweep, red shutter warning, white-red firing aperture.
• Fixed brass tripod with a rotating mirror head.
• Triangular sight wedge, never a vague radial detection field.
• Neutral sweep uses Sun; acquisition shifts to Danger and accelerates its pulse.
• The head snaps back to patrol when the player enters shadow.

The Watcher should read as station machinery, not a soldier. This keeps the game focused on systems and signals rather than combat.

Environment kit

Build the jam environments from a small reusable kit:

• industrial and stone modules built from 18px Kenney tiles at integer 2x, producing a 36px world grid;
• one arch/window module that can contain a sunlight zone;
• brass rail and cable background strips;
• inactive and active light-platform states;
• checkpoint mirror pedestal;
• cipher plate and terminal console;
• one foreground shadow mask and two distant background layers.

Use silhouettes and color blocking first. Decorative cracks, cables, screws, and dust are a final pass.

Interface direction

The HUD is low-chrome and always readable against both states:

• Charge: a horizontal or shallow arc meter in the upper-left, labeled with a cell icon rather than a number by default.
• Exposure: a small open/closed shutter icon next to charge. This duplicates the world lighting cue.
• Cipher notebook: discovered mappings appear as compact glyph -> letter cards along the lower edge and collapse when not changing.
• Terminal: centered dark panel with a segmented brass frame, full glyph sequence, discovered mappings, text entry, and explicit submit/cancel prompts.

Use a clean humanist sans-serif for instructions and a monospaced face for terminal output. Avoid distressed fonts for body text.

When the terminal opens, gameplay pauses. The background darkens but remains visible so the puzzle still feels located in the level.

Motion and effects

Prioritize five effects in this order:

1. Light-entry rim and dust response.
2. Short dash trail using two or three fading silhouettes.
3. Sentry warning pulse and beam contraction.
4. Death as the light cell collapsing to a point before respawn.
5. Cipher success as shutters opening and a signal beam leaving the station.

Avoid continuous full-screen bloom, camera shake on ordinary movement, and dense particles that obscure platform edges.

Audio direction

Event or layer	Sound language
Sunlight ambience	Warm electrical hum, glass resonance, sparse wind
Shadow ambience	Low room tone, distant relay clicks, reduced high frequencies
Charge fill	Quiet rising harmonic, never a constant alarm
Low charge	Slow mechanical tick that accelerates below 15%
Dash	Shutter snap plus short air cut
Sentry acquisition	Two-stage relay click followed by a 0.35s warning tone
Glyph discovered	Single tuned telegraph key click
Cipher solved	Four-note signal phrase reused in the win state

Music is optional. If time is limited, strong ambience and state feedback are more valuable than a looping score.

Asset budget

Domain	Jam target
Player	1 sprite set: idle, run, jump/fall, dash, death
Enemy	1 Watcher with sweep and alert states
Environment	8-12 modular pieces plus 3 background layers
Interactables	Platform, checkpoint, clue plate, terminal
UI	Charge, exposure, mapping card, terminal panel
Effects	Light dust, dash trail, warning pulse, death collapse, success beam
Audio	8-12 one-shots plus 2 ambient loops

If custom art falls behind, ship flat silhouettes with this palette. Do not mix unrelated asset packs merely to add detail.

The exact reusable files, excluded packs, tint rules, and custom backlog are defined in Asset Reuse Plan.

Theme acceptance criteria

• A still screenshot clearly separates sunlight, shadow, solid terrain, and inactive light platforms.
• The player and Watcher remain identifiable at game scale.
• Exposure and sentry warning are readable without relying on color.
• Cipher UI looks related to machinery already present in the level.
• The final signal uses the same visual and audio motifs introduced by checkpoints and clue discovery.