[Bug]: No segmentation maps for MPM objects.

[wisdomikezogwo]

Bug Description

I trying to simulate some data and save the rgb and segmentation mask videos, however i just noticed that all MPM materials don't get visualized in the segmentations masks produced, see attached videos. Wondering why, especially as when i extract out the normal I can see the MPM object.

The demo code below uses entity level segmentation, and when i tried geom I get an assertion error :

Traceback (most recent call last):
  File "/simulate/diff_push.py", line 109, in <module>
    scene.build()
  File "/scram/miniconda3/envs/cosmos-predict1/lib/python3.10/site-packages/genesis/utils/misc.py", line 91, in wrapper
    return method(self, *args, **kwargs)
  File "/scram/miniconda3/envs/cosmos-predict1/lib/python3.10/site-packages/genesis/engine/scene.py", line 613, in build
    self._visualizer.build()
  File "/scram/miniconda3/envs/cosmos-predict1/lib/python3.10/site-packages/genesis/vis/visualizer.py", line 140, in build
    self._context.build(self._scene)
  File "/scram/miniconda3/envs/cosmos-predict1/lib/python3.10/site-packages/genesis/vis/rasterizer_context.py", line 102, in build
    self.generate_seg_vars()
  File "/scram/miniconda3/envs/cosmos-predict1/lib/python3.10/site-packages/genesis/vis/rasterizer_context.py", line 855, in generate_seg_vars
    assert False, "geom level segmentation not supported yet"
AssertionError: geom level segmentation not supported yet

[Genesis] [17:42:50] [ERROR] AssertionError: geom level segmentation not supported yet
[Genesis] [17:42:50] [INFO] 💤 Exiting Genesis and caching compiled kernels...

Steps to Reproduce

import argparse
import pathlib 
import numpy as np
import genesis as gs

import cv2
import numpy as np


# ─────────────────── CLI ───────────────────
cli = argparse.ArgumentParser()
cli.add_argument("--velocity", nargs=3, type=float, default=[2.0, 0.0, 0.0],
                help="Initial ball velocity (m/s) in X Y Z")

cli.add_argument("--out_dir", default="frames")


args = cli.parse_args()


# ───────── scene constants ───────
TABLE_TOP_Z = 0.0                   # height of tabletop (top surface)
BALL_R      = 0.05
table_friction = 0.15      # plane + box share the same coeff

PHYS_HZ, SUBSTEPS = 240, 12
VID_FPS, FRAMES   = 24, 121
STEP_RATIO        = PHYS_HZ // VID_FPS  # 10
TOTAL_STEPS       = int(((FRAMES * STEP_RATIO)/5) * 2)  # 1210
print(f"TOTAL_STEPS: {TOTAL_STEPS}")


    
def initialization(args, substeps=SUBSTEPS, dt=1/PHYS_HZ, mpm_lower_bound=(-2.0, -2.0, -2.0), mpm_upper_bound=(2.0, 2.0, 2.0), friction=0.15, show_viewer=False):
    ########################## init ##########################
    gs.init(backend=gs.gpu)

    scene = gs.Scene(
        sim_options=gs.options.SimOptions(
            dt=dt,
            substeps=substeps,
            gravity=(0, 0, -9.81),
        ),
        mpm_options=gs.options.MPMOptions(
            lower_bound=mpm_lower_bound,
            upper_bound=mpm_upper_bound,
        ),
        show_viewer=show_viewer,
        vis_options = gs.options.VisOptions(
            show_world_frame = False,
            segmentation_level='entity',
            world_frame_size = 1.0,
            show_link_frame  = False,
            show_cameras     = False,
            plane_reflection = True,
        ),
        show_FPS=False,     
    )

    # ─────── ground  ────────
    ground = scene.add_entity(gs.morphs.Plane(collision=True))
    ground.set_friction(friction)

    return scene

# ───────── Genesis init ─────────
scene = initialization(args, mpm_lower_bound=(-1.0, -1.0, -1.0), mpm_upper_bound=(1.0, 1.0, 1.0))


# ─────── obstacle ──────
obst_morph = gs.morphs.Sphere(pos=(0.30, 0.0, TABLE_TOP_Z + BALL_R + 1e-3), radius=BALL_R)

obst_surf = gs.surfaces.Default(color=(0.4, 0.55, 0.9))

obst_mat = gs.materials.MPM.ElastoPlastic(
        E=1e6,  # Young's modulus
        nu=0.2,  # Poisson's ratio
        rho=1000.0,  # density (kg/m^3)
)

object_1 = scene.add_entity(
    morph=obst_morph,
    material=obst_mat, #gs.materials.Rigid(rho=250, friction=0.3),
    surface=obst_surf,
)


# ───────────── ball ─────────────
ball_z = TABLE_TOP_Z + BALL_R + 1e-3    # 1 mm clearance
ball = scene.add_entity(
    morph=gs.morphs.Sphere(pos=(-0.45, 0, ball_z), radius=BALL_R),
    material=gs.materials.Rigid(rho=250, coup_restitution=0, friction=0.3),
    surface=gs.surfaces.Default(color=(1, 0, 0)),
)

# ───────────── camera ────────────
cam = scene.add_camera(
    pos=(0, -2.0, TABLE_TOP_Z + 0.45),
    lookat=(0, 0, TABLE_TOP_Z + 0.02),
    fov=35, res=(640, 480), GUI=False,
)


# ─────────── simulate ────────────
scene.build()
ball.set_dofs_velocity(np.array([*args.velocity, 0, 0, 0], dtype=np.float32))

out_dir = pathlib.Path(args.out_dir); out_dir.mkdir(exist_ok=True)
video_file = out_dir / "resource.mp4"

cam.start_recording()
seg_frames = []
for step in range(TOTAL_STEPS):
    scene.step()
    if step % STEP_RATIO == 0:
        rgb_img, depth_img, seg_img, normal_img = cam.render(
                rgb=True, 
                depth=True, 
                segmentation=True, 
                colorize_seg=False,  # Keep raw object indices
                normal=True
            )
        seg_frames.append(seg_img)
cam.stop_recording(save_to_filename=str(video_file), fps=VID_FPS)


height, width = seg_frames[0].shape[:2]
fourcc = cv2.VideoWriter_fourcc(*'mp4v')
out = cv2.VideoWriter(str(out_dir / "resource_seg.mp4"), fourcc, VID_FPS, (width, height), False)
for frame in seg_frames:
    if frame.dtype != np.uint8:
        if frame.max() <= 1.0:  # Normalized float
            frame = (frame * 255).astype(np.uint8)
        else:  # Handle depth maps or other ranges
            frame = ((frame - frame.min()) / (frame.max() - frame.min()) * 255).astype(np.uint8)
    out.write(frame)
out.release()
            

print(f"✓ saved {FRAMES}-frame clip → {video_file}")

Make sure to attached any needed assets (here attachement.xml)!

Expected Behavior

I expect the stationary sphere, thats hit to be visible in the segmentation mask as it is in the rgb image.

Screenshots/Videos

https://github.com/user-attachments/assets/b5f17217-918c-4b51-8c74-430ffd019a6d https://github.com/user-attachments/assets/3d3717b1-1e55-4ebb-b696-e96ca90611e5

Relevant log output

Environment

• OS: [Rocky Linux 8.9]
• GPU/CPU [A100 80GB]
• GPU-driver version (565.57.01)
• CUDA / CUDA-toolkit version (12.4)

Release version or Commit ID

0.2.1 commit: https://github.com/Genesis-Embodied-AI/Genesis/commit/ea31abc182b2a7aad2696c15cd24bab141ddb7d7

Additional Context

No response