threejs-scenes

When to use this skill

ALWAYS use this skill when the user mentions:

• Scene as root, scene.background, environment or skyball setup at scene level
• Fog or FogExp2 parameters (near, far, color, density) and interaction with camera far plane
• Organizing render lists conceptually (children of scene)

IMPORTANT: scenes vs textures vs loaders

| Concern | Skill | |---------|--------| | Scene + fog API | threejs-scenes | | Texture sampling, PMREM generator usage | threejs-textures | | Fetching HDR/glTF | threejs-loaders |

Trigger phrases include:

• "Scene", "Fog", "FogExp2", "background", "雾"
• "场景根节点", "线性雾", "指数雾"

How to use this skill

1. Instantiate Scene and add lights/meshes/cameras as children per graph rules (threejs-objects).
2. Choose fog: linear Fog vs exponential FogExp2 for outdoor/horizon feel.
3. Tune fog near/far alongside camera far to avoid clipping artifacts.
4. Set scene.background to Color, Texture, or cube map per docs; env lighting still needs matching renderer/material settings.
5. When user wants IBL from HDR file, point to loaders → textures → materials pipeline explicitly.
6. Document that fog does not replace frustum culling for performance.

See examples/workflow-fog-background.md.

Doc map (official)

| Docs section | Representative links | |--------------|----------------------| | Scenes | https://threejs.org/docs/#Scenes | | Scenes | https://threejs.org/docs/Scene.html | | Fog | https://threejs.org/docs/Fog.html | | FogExp2 | https://threejs.org/docs/FogExp2.html |

Scope

• In scope: Scene, fog types, background field semantics at API level.
• Out of scope: HDR / glTF file fetch (threejs-loaders); PMREM and texture sampling (threejs-textures); tone mapping / output color space defaults (threejs-renderers); full-screen fog-only post stack (threejs-postprocessing) unless tying to scene Fog; custom atmospheric scattering shaders beyond core fog API.

Common pitfalls and best practices

• Fog color should harmonize with background to hide the horizon seam.
• Very large far on camera with fog still needs scene scale consistency.
• background rotation/intensity features depend on renderer version—cite current docs.

Documentation and version

Scene, Fog, and background fields are documented under Scenes in three.js docs. Environment-related visuals often combine this skill with threejs-textures (PMREM) and threejs-loaders (HDR files)—link those pages when the user moves from “fog color” to “HDR sky”.

Agent response checklist

When answering under this skill, prefer responses that:

1. Link Scene, Fog, or FogExp2 official pages.
2. Relate fog distances to threejs-camera far plane and world scale.
3. Defer PMREM/HDR file steps to threejs-textures / threejs-loaders with one sentence each.
4. Avoid duplicating full color-management tutorials—point to renderer + textures skills.

References

• https://threejs.org/docs/Scene.html
• https://threejs.org/docs/Fog.html
• https://threejs.org/docs/FogExp2.html

Keywords

English: scene, fog, fogexp2, background, environment, three.js

中文： 场景、雾、Fog、背景、环境、three.js

能力边界

✅ 适用场景

• 当你需要使用此技能对应的技术栈时
• 当项目需要遵循最佳实践时
• 当需要快速上手或深入理解核心概念时

⚠️ 需要注意

• 复杂业务逻辑需要结合具体场景调整
• 性能优化需要根据实际数据量评估

❌ 不适用场景

• 不相关的技术栈或框架
• 需要完全自定义的特殊场景

常见陷阱 (Gotchas)

1. 版本兼容性：注意框架版本与依赖库的兼容性，不同版本 API 可能有差异
2. 配置文件格式：配置文件格式错误是最常见的问题，建议使用编辑器的语法检查
3. 环境变量：确保所有必要的环境变量已正确设置，敏感信息不要硬编码
4. 依赖冲突：多版本共存时注意依赖冲突，使用 lock 文件锁定版本
5. 性能陷阱：大数据量场景下注意性能优化，避免 N+1 查询等常见问题

使用流程

Step 1: 环境准备

确保开发环境已安装必要的依赖和工具。

Step 2: 配置初始化

根据项目需求进行基础配置。

Step 3: 核心功能使用

按照示例代码实现核心功能。

Step 4: 测试验证

运行测试确保功能正常。

Step 5: 部署上线

完成开发后进行部署和监控。