perf(rerun): render voxel maps as Points3D spheres instead of Boxes3D

[ruthwikdasyam]

Problem

endering each voxel as an rr.Boxes3D instance is expensive - each box is 12 line segments in the
Rerun line renderer, whereas rr.Points3D with a world-space radius is a single billboarded quad per point

Closes #1631

Solution

Flip all PointCloud2.to_rerun(mode="boxes") callers to mode="spheres". Same world-space voxel footprint, renders as spheres instead of cubes, ~10x cheaper at high point counts

• option to switch to mode=boxes is still present
• voxel sizes are reduced to 0.05 (from 0.1), as the rerun maintains good fps with spherical voxels
• toggling default set to 0 hz. Can be adjusted when needed (if, boxes are used)

Breaking Changes

None

How to Test

• Any blueprint should launch rerun - with spherical voxels
  quick test -> `dimos --replay --replay-dir=unitree_go2_bigoffice run unitree-go2'

Contributor License Agreement

• I have read and approved the CLA.

Looks good. Able to maintain good fps (~20) with 400k voxels at 0.05 radius

[greptile-apps]

Greptile Summary

This PR replaces rr.Boxes3D voxel rendering with rr.Points3D (world-space sphere radius) across all Go2, G1, and FastLio2 blueprints, and lowers the voxel size from 0.1 to 0.05 m. The change is well-motivated — each box costs 12 line segments vs. one billboarded quad for a point — and the PR description includes measured results (~20 fps at 400k voxels).

Confidence Score: 5/5

Safe to merge — all remaining findings are P2 style/robustness suggestions with no impact on correctness or runtime behavior.

The change is a straightforward caller-side swap (mode=spheres) that uses an existing, well-tested rr.Points3D code path. No data loss, no breaking API change. The three P2 comments (stale docstring, else-fallthrough, voxel-size inconsistency in the security blueprint) do not affect the correctness of the primary render path.

dimos/msgs/sensor_msgs/PointCloud2.py (docstring and else-fallthrough); dimos/robot/unitree/go2/blueprints/agentic/unitree_go2_security.py (voxel_size still 0.1)

Important Files Changed

Filename	Overview
dimos/msgs/sensor_msgs/PointCloud2.py	Added "spheres" mode to to_rerun() using rr.Points3D with world-space radii; voxel_size default lowered to 0.05; stale docstring claims "boxes" is default and else-fallthrough silently accepts invalid mode strings.
dimos/hardware/sensors/lidar/fastlio2/fastlio_blueprints.py	All three FastLio2 visual overrides switched from mode="boxes" to mode="spheres" with voxel_size=0.05; straightforward and consistent.
dimos/robot/unitree/go2/blueprints/basic/unitree_go2_basic.py	Global map visual override switched to mode="spheres" with voxel_size=0.05; max_hz for global_map, color_image, and global_costmap set to 0 (unlimited, filtered by if hz > 0 in bridge).
dimos/robot/unitree/go2/blueprints/agentic/unitree_go2_security.py	Global map override changed to mode="spheres" but retains voxel_size=0.1, inconsistent with the basic Go2 blueprint's 0.05; may be intentional but is undocumented.
dimos/robot/unitree/g1/blueprints/primitive/uintree_g1_primitive_no_nav.py	Global map override switched to mode="spheres" while intentionally keeping voxel_size=0.1 for the G1 (larger robot, different scale); consistent with robot geometry.
dimos/robot/unitree/go2/blueprints/smart/unitree_go2.py	VoxelGridMapper voxel_size updated from 0.1 to 0.05; no other changes.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A["PointCloud2.to_rerun(voxel_size, mode, ...)"] --> B{mode?}
    B -- "points" --> C["rr.Points3D(positions)\nno radii — raw point cloud"]
    B -- "boxes" --> D["rr.Boxes3D(centers, half_sizes)\n12 line segments per voxel"]
    B -- "spheres\n(all blueprint callers)" --> E["rr.Points3D(positions, radii=voxel_size/2)\nbillboarded quad per voxel — ~10x cheaper"]
    B -- "any other string\n(silent fallthrough)" --> E
    E --> F["Rerun viewer\n~20 fps @ 400k voxels"]
    D --> G["Rerun viewer\n~2 fps @ 400k voxels"]

Loading

Comments Outside Diff (2)

1. dimos/msgs/sensor_msgs/PointCloud2.py, line 665 (link)

   Stale docstring claims "boxes" is the default mode

   The docstring says "boxes" for cubes (default), but the parameter signature has mode: str = "points". Any caller reading the docstring will form the wrong expectation about the default rendering mode.

2. dimos/msgs/sensor_msgs/PointCloud2.py, line 705-711 (link)

   Silent fallthrough on invalid mode values

   The else branch silently treats any unrecognised string (e.g. mode="sphere", mode="Spheres") as spheres. A typo will render without warning, which is hard to debug. Consider an explicit elif mode == "spheres": guard followed by a ValueError:

_{Reviews (1): Last reviewed commit: "voxel size to 0.05" | Re-trigger Greptile}

[leshy]

Hey we can probably just change PointCloud2 to_rerun() function to do this by default? and we can just delete explicit overrides from all blueprints