threejs-camera

When to use this skill

ALWAYS use this skill when the user mentions:

• Switching perspective vs orthographic, fov, aspect, zoom, near, far
• CubeCamera for real-time environment maps or reflections (update rate caveats)
• ArrayCamera/StereoCamera for multi-view or stereo off-axis projection (non-XR)

IMPORTANT: camera vs webxr vs post

| Topic | Skill | |-------|--------| | Standard desktop projection | threejs-camera | | XR reference spaces, IPD | threejs-webxr | | Offscreen pass cameras inside composer | threejs-postprocessing |

Trigger phrases include:

• "PerspectiveCamera", "OrthographicCamera", "CubeCamera", "aspect", "near", "far"
• "透视相机", "正交", "立方体相机"

How to use this skill

1. Perspective: set aspect = width/height; update on resize (threejs-renderers example workflow).
2. Orthographic: define left/right/top/bottom in world units for CAD/2.5D views.
3. Near/far: balance depth precision vs containing scene bounds; relate to fog (threejs-scenes).
4. CubeCamera: position at reflection probe; call update when scene static enough; use render target outputs per docs.
5. Stereo/Array: advanced; cite docs for eye parameters; defer XR to threejs-webxr.
6. Projection matrix: call updateProjectionMatrix() after parameter edits.
7. Helpers: CameraHelper lives in threejs-helpers.

See examples/workflow-perspective-resize.md.

Doc map (official)

| Docs section | Representative links | |--------------|----------------------| | Cameras (index) | https://threejs.org/docs/#Cameras | | Cameras | https://threejs.org/docs/Camera.html | | Perspective | https://threejs.org/docs/PerspectiveCamera.html | | Orthographic | https://threejs.org/docs/OrthographicCamera.html | | Cube | https://threejs.org/docs/CubeCamera.html | | Multi-view | https://threejs.org/docs/ArrayCamera.html | | Stereo (non-XR) | https://threejs.org/docs/StereoCamera.html |

Scope

• In scope: Core camera classes and parameters; cube/array/stereo overview.
• Out of scope: WebXR reference spaces, eye matrices, session lifecycle (threejs-webxr); shadow map camera tuning (threejs-lights); pass-internal cameras in composer (threejs-postprocessing).

Common pitfalls and best practices

• Wrong aspect after resize stretches image—always sync with canvas.
• Too small near hurts depth precision in large worlds.
• CubeCamera every frame is expensive—throttle for performance.

Documentation and version

Camera parameters and CubeCamera update behavior follow the Cameras section of three.js docs. WebXR uses different projection paths—hand off to threejs-webxr when the user mentions headsets or reference spaces.

Agent response checklist

When answering under this skill, prefer responses that:

1. Link PerspectiveCamera, OrthographicCamera, or CubeCamera as relevant.
2. Pair resize with threejs-renderers setSize / DPR patterns when relevant.
3. Route XR/WebXRManager questions to threejs-webxr after one-line renderer mention.
4. Mention updateProjectionMatrix() after intrinsic changes.
5. Use threejs-helpers CameraHelper for shadow frustum debug when discussing lights.

References

• https://threejs.org/docs/#Cameras
• https://threejs.org/docs/PerspectiveCamera.html
• https://threejs.org/docs/CubeCamera.html

Keywords

English: perspectivecamera, orthographiccamera, cubecamera, projection, aspect, near, far, three.js

中文： 相机、透视、正交、投影、近裁剪、远裁剪、CubeCamera、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。