# meshToWireframe

Builds a deduplicated line-list index buffer out of a readable triangle-list mesh. Use it alongside `wireframeMaterial` to visualize topology edges during debugging sessions.

## Import

```ts
import { meshToWireframe } from "@vgpu/render/inspect";
```

## Signature

```ts
export function meshToWireframe(mesh: Mesh, device: Device): Promise<WireframeMesh>;
```

## Parameters

| Param | Type | Required | Default | Notes |
|---|---|---|---|---|
| mesh | Mesh | ✔ | — | Must have a vertex buffer created with `GPUBufferUsage.COPY_SRC`; otherwise the function cannot read vertex positions. |
| device | Device | ✔ | — | Supplies the command encoder, index buffer, and queue submit used to bake the wireframe lines. |

**Returns:** `Promise<WireframeMesh>` — frozen mesh-like object that reuses the source `vertexBuffer`, exposes a raw `indexBuffer`, reports whether the index data is `uint16` or `uint32`, and includes the deduplicated `lineCount`.

**Throws:** `VGPU-CORE-INVALID-USAGE` when the source mesh lacks a readable vertex buffer; fix by creating the geometry via `geometry(gpu, ...)` or promoting it through `meshToReadable` first.

## Examples

```ts
import { createMockAdapter } from "@vgpu/adapter-mock";
import { meshToReadable, meshToWireframe, wireframeMaterial } from "@vgpu/render/inspect";
import { init, geometry } from "vgpu/mock";
import { box } from "vgpu/scene";

async function main(): Promise<void> {
  const adapter = createMockAdapter();
  const gpu = await init({ adapter });
  const solid = geometry(gpu, box({ size: 1 }));
  const readable = await meshToReadable(solid as never, gpu.device);
  const wireframe = await meshToWireframe(readable, gpu.device);
  const inspector = wireframeMaterial({ device: gpu.device });

  console.log(wireframe.lineCount); // 12 for a cube
  inspector.pipeline; // ready-to-use GPURenderPipeline
}

main().catch((error) => {
  console.error(error);
});
```

## Notes

- The helper quantizes edge endpoints to a `1e-6` grid before it deduplicates them; bake tiny debug meshes at a larger scale if you need finer detail.
- Triangle pairs that share a coplanar face have their diagonal removed by comparing face normals, so smooth surfaces only emit silhouette edges.
- The returned `indexBuffer` is a raw `GPUBuffer`. Destroy it manually when the wireframe is no longer needed or rely on `device.destroy()` during teardown.
- **See also:** `meshToReadable`, `wireframeMaterial`, `InspectMaterial`