Abstract
Problem: How does a veteran game developer evolve a simple prototype ("toy") toward something resembling a real game, and what does that arc look like in practice?
Approach: Tim Cain walks through the final round of polish on his space game prototype "Star Traders," covering new shaders, trail renderers, particle effects, a full upgrade system, wave-based enemy progression, and a live playthrough.
Findings: Even without a production schedule, iterative layering of visual effects (shield shaders, photon trails, smoke particles) and systems design (six upgradeable ship subsystems, cargo economy, wave escalation with corvettes) can transform a bare-bones toy into something that looks and feels close to a real game.
Key insight: The journey from "toy" to "game" is an arc of incremental systems — each pass adds visual feedback, player agency, or mechanical depth, and the compound effect is far greater than the sum of individual additions.
Source
Shader and Visual Upgrades
Tim opens by explaining the visual polish pass he did before archiving the project:
- Shield shader overhaul: The new shield shader combines a noise filter with UV time-based scrolling on top of the existing Fresnel effect and color tinting. The result is a dynamic, plasma-like bubble instead of a flat shell.
- Photon shader + trail: Plain yellow projectiles were replaced with a plasma-ball shader (similar to shields but without Fresnel). Each photon also got a Unity Trail Renderer — yellow fading to white, with decreasing alpha and width. This makes projectile paths readable and visually satisfying.
- Ship smoke trails via particle effects: Tim experimented with trail renderers on enemy ships but found it looked too high-tech for the retro aesthetic. Instead he used Unity's particle system to emit small puffs of smoke that expand and fade over ~10 seconds. The effect looks like internal combustion engines — intentionally archaic and funny — but also makes ships much easier to track visually. He kept the smoke translucent so it wouldn't obscure shooting.
Player Ship Systems
The player ship has six subsystems, visible in the bottom-right HUD:
| System | Function |
|---|---|
| Shields (S) | Absorbs incoming photons. Shown as a tint on the viewscreen rather than a bubble. Damaged shields have a chance to let hits through; broken shields let everything through. |
| Scanner (L) | Long-range radar displayed bottom-left, showing enemies in front and behind in 2D. |
| Tracker (T) | Middle-click to bracket-lock an enemy. Also governs how well tracking photons (an upgrade) home in on targets. |
| Engines (E) | Controls speed. Degrades as damaged, fully broken means you can't move (but can still shoot). |
| Tractor Beam (B) | Pulls in cargo from destroyed ships. Upgrades increase pull speed and radius. |
| Hull (H) | Hit points. When hull reaches zero, you die. |
All six systems have three visual/audio states: healthy, damaged, and broken. Every system except Hull can be fully broken and you keep playing — Hull at zero is game over.
Upgrade Economy
- Destroying enemy ships drops cargo containers that float in space.
- Flying over cargo picks it up (or the tractor beam slowly pulls it in).
- When the cargo bar fills, you're offered a choice of three random upgradeable systems — pick one to upgrade and fully repair.
- Systems at max upgrade stop appearing in the selection.
Wave Progression and the Corvette
- Waves 1–4: Increasing numbers of small unshielded ships (starting at 1–2, reaching 6–7 by wave 4).
- Wave 5: A large Corvette appears — shielded, fires multiple photons, and launches additional small ships. It's a priority target.
- Waves 6+: Small ships start gaining shields and multi-photon attacks, scaling up with each wave.
- Every 5th wave: Another Corvette appears alongside the upgraded small ships.
- Arenas are randomly selected: planet, star base, or asteroid field.
Live Playthrough Observations
Tim narrates a full run that ends at wave 5 (30 ships encountered):
- Trails on both photons and ships make combat visually readable — you can follow smoke trails to locate ships even off-screen.
- The upgrade decision point creates meaningful tension: do you repair shields or boost engines?
- The Corvette at wave 5 is a dramatic difficulty spike — Tim's run ended there with 10 simultaneous enemies and overheated photons.
- Tim notes that by his standards "this is not a game" but acknowledges it's dramatically closer to one than when the toy updates began.
The Toy-to-Game Arc
Tim frames this series as a demonstration of iterative prototyping philosophy:
- Start with ideas, turn them into a toy (something you can play with).
- Layer systems, feedback, and polish incrementally.
- Work on it when it's fun — no schedule, no obligations.
- Archive and walk away when you want to explore other things.
- The project taught him shaders, trail renderers, and particle effects — skills he'd never deeply engaged with before, and which are now giving him ideas for future projects.
He confirms this is the last toy update "for a while" — the code and assets are archived to the cloud, and he's moving on to other Fun Friday topics.