Mapping from polyRef -> tilePolyIndex

[rob-myers]

Given a polygon reference polyRef (a number) we can visualise it using tile.detailMeshes(tilePolyIndex) as in getDebugNavMesh.

In particular:

• polyRef is global over the entire navMesh
• 0 ≤ tilePolyIndex < tile.polyCount().

In order to map between them I am currently building a lookup from poly.raw.ptr to each respective tilePolyIndex. I also have to update this lookup whenever a tile changes e.g. add/remove obstacle.

Is there a better way?

[rob-myers]

In this case we could expose dtNavMesh::decodePolyId.

We could also provide its inverse i.e. dtNavMesh::encodePolyId.

[isaac-mason]

No problems @rob-myers!

Are you seeing this issue on the "Click Nearby Polygons" storybook?

[rob-myers]

Yeah @isaac-mason , the "Click Nearby Polygons" story.

But after another look I'm probably misunderstanding the "detail mesh".

The AABB of the triangle containing 322 does not intersect the cube.
However, 322 actually corresponds to this triangle:

So presumably I was looking at a "detail triangle", without realising it.

[isaac-mason]

Somewhat related - I've been meaning to improve the threejs visualisation helpers for a while - #165

I'm going to put some more energy into this soon. It should help with investigating and understanding things like this.

[isaac-mason]

fyi @rob-myers - added a DebugDrawer class to @recast-navigation/three

https://recast-navigation-js.isaacmason.com/?path=/story/debug-three-debug-drawer--poly-mesh
https://recast-navigation-js.isaacmason.com/?path=/story/debug-three-debug-drawer--poly-mesh-detail

[rob-myers]

@isaac-mason great job on all those examples!