# Troubleshooting
This page lists common problems and the first places to look.
## The output is blank
Check:
- The scene has an active camera.
- The camera is looking at the model.
- The model was instantiated into the scene.
- The model bounds are inside the camera frustum.
- `prepare()` was called after the latest scene or asset change.
- The renderer target size is non-zero.
Useful examples:
- `examples/first_visible_render.rs`
- `examples/camera_framing.rs`
- `examples/headless_ci.rs`
## The model is too large or too small
Check unit metadata and import options.
See [Units, axes, and handedness](guides/units-axes-handedness.md).
## The model is rotated sideways
Check the authored up-axis and coordinate-system metadata.
See:
- [Units, axes, and handedness](guides/units-axes-handedness.md)
- [Troubleshooting misplaced assets](guides/troubleshooting-misplaced-assets.md)
## Textures are missing
Check:
- external image paths are correct,
- browser URLs are fetchable,
- image files are deployed next to the glTF file,
- optional texture features are enabled when required,
- unsupported required extensions are reported in the asset error.
See [Assets](assets.md).
## Rendering fails after a resize
Resize and surface events invalidate prepared renderer state. Forward the event
to the renderer and call `prepare()` again before rendering.
See [Lifecycle](lifecycle.md).
## Browser rendering is unavailable
Check:
- browser support for WebGPU or WebGL2,
- secure context requirements for WebGPU,
- canvas creation,
- requested backend,
- capability report,
- console errors from asset fetching.
See [Browser and WASM](browser.md).
## Picking misses objects
Check:
- camera and viewport dimensions,
- cursor coordinate conversion,
- object visibility,
- layer masks,
- scene preparation after moving objects.
Start with `examples/picking_selection_hover.rs`.
## Anchors or connectors do not align
Check:
- connector forward/up vectors,
- source units,
- coordinate-system conversion,
- left-handed versus right-handed data,
- whether the anchor belongs to the expected imported node.
See:
- [Place and connect objects](guides/place-and-connect-objects.md)
- [Authoring glTF anchors and connectors](guides/authoring-gltf-anchors-connectors.md)
- [Troubleshooting misplaced assets](guides/troubleshooting-misplaced-assets.md)