The dev chat nailed it. The bitwise extraction (`(v >>> 1) & 0xF`) perfectly
maps to the `VOXEL_MEMORY_ARENA` specification we designed in Phase 1, and the
neighbor culling elegantly handles the transition between hard cubes and
sloped wedges.

To see this in action, we need to do two things:

### Step 1: Update the Worker

Save the provided code from the dev chat into `/mnt/mesh_shared/3d/3D-TS/mesh_w
orker.ts`.

### Step 2: Build with Ramps

Right now, your left-click in `renderer.ts` places a standard cube (`voxelData
= 1`). We need to change that to place our new Ramp shape.

According to our 32-bit bitmask:

* Bit 0 (Filled) = `1`
* Bits 1-4 (Point Type) = `1` (Ramp)
* Resulting integer: `1 | (1 << 1)` = `3`.

Open your `/mnt/mesh_shared/3d/web/src/renderer.ts` and locate the pointer
down logic (around line 147). Change `voxelData = 1` to `voxelData = 3`:

```typescript
    if (isLeftClick && !isShiftLeftClick) {
        // Place block: move outward from the face
        targetPoint = pickedPoint.add(normal.scale(0.5));
        voxelData = 3; // 32-bit Mask: 1 (Filled) | (1 << 1) (Point Type 1 =
Ramp)
    } else if (isRightClick || isShiftLeftClick) {
        // Remove block: move inward from the face
        targetPoint = pickedPoint.subtract(normal.scale(0.5));
        voxelData = 0;
    }

```

*(You can leave the "seed" block at the top of the file as `1` so you still
have a flat cube to start clicking on).*

### The Test

Save both files, let Vite reload, and left-click on top of the green seed
cube.

You should instantly see a sloped ramp snap into place! If you build a few of
them side-by-side, they will form a smooth continuous slope, but if you look
underneath them, they will remain completely solid and watertight, just as you
requested.

Give it a try and let me know how it looksand if the face winding (the
direction the slope is facing) calculated by the dev chat looks correct to
you!