3d-games

Guidance for building 3D games, covering how scenes are rendered, how shaders change the appearance of objects, how physics collisions work, and how cameras are designed. A shader is a small program that controls how graphics are drawn.

In plain words
What is it for?
Planning rendering optimizations, choosing or writing shaders, selecting collision shapes, setting up physics checks, and designing 3D camera systems.
Why use it?
It helps developers make 3D scenes behave and look correctly while avoiding unnecessary rendering and physics work.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/felipeslo/opencode-kit/3d-games
Any agent
npx skills add felipeslo/opencode-kit --skill 3d-games
Clone the repo
git clone --depth 1 https://github.com/felipeslo/opencode-kit

Made for: Claude Code, Codex.

Per session 18 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 637 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 92% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00018 $0.00637
Opus 5 $0.00009 $0.00318
Sonnet 5 $0.00004 $0.00127
Haiku 4.5 $0.00002 $0.00064

Measured 2d ago against content hash 4c18e31e2f3a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

3d-games scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

92% identical to 3d-games — 1 line differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.opencode/skills/game-development/3d-games/SKILL.md · 135 lines

How it starts

The opening of the file, as written. The whole thing — 135 lines — stays where its author put it; the contents beside it link to each section on GitHub.

3D Game Development

Principles for 3D game systems.


1. Rendering Pipeline

Stages

1. Vertex Processing → Transform geometry
2. Rasterization → Convert to pixels
3. Fragment Processing → Color pixels
4. Output → To screen

Optimization Principles

Technique Purpose
Frustum culling Don't render off-screen
Occlusion culling Don't render hidden
LOD Less detail at distance
Batching Combine draw calls

2. Shader Principles

Shader Types

Type Purpose
Vertex Position, normals
Fragment/Pixel Color, lighting
Compute General computation

When to Write Custom Shaders

  • Special effects (water, fire, portals)
  • Stylized rendering (toon, sketch)
  • Performance optimization
  • Unique visual identity

3. 3D Physics

Collision Shapes

Shape Use Case
Box Buildings, crates
Sphere Balls, quick checks
Capsule Characters
Mesh Terrain (expensive)

Principles

  • Simple colliders, complex visuals
  • Layer-based filtering
  • Raycasting for line-of-sight

4. Camera Systems

Camera Types

Type Use
Third-person Action, adventure
First-person Immersive, FPS
Isometric Strategy, RPG
Orbital Inspection, editors

Camera Feel

  • Smooth following (lerp)
  • Collision avoidance
  • Look-ahead for movement
  • FOV changes for speed

5. Lighting

Light Types

Type Use
Directional Sun, moon
Point Lamps, torches
Spot Flashlight, stage
Ambient Base illumination

Performance Consideration

  • Real-time shadows are expensive
  • Bake when possible
  • Shadow cascades for large worlds

6. Level of Detail (LOD)

LOD Strategy

Distance Model
Near Full detail
Medium 50% triangles
Far 25% or billboard

Read the full file on GitHub · 135 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 135 lines · 18 tokens per session scan A 4c18e31e2f3a

Subscribe to this mod's changes

3d-games is a skill published in the GitHub repository felipeslo/opencode-kit (2 stars, last pushed 5mo ago), licensed MIT. It adds 18 tokens to every session and 637 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 92% identical to 3d-games, differing in 1 line, and is treated as a copy.

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