Source code for mujoco.mjx._src.render_util

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"""JAX render utilities for unpacking render output from MuJoCo Warp."""

from typing import TYPE_CHECKING

import jax
import jax.numpy as jnp
import mujoco.mjx.warp as mjxw

if TYPE_CHECKING:
  from mujoco.mjx.warp.render_context import RenderContextPytree


def _get_camera_resolution(warp_rc, cam_id: int) -> tuple[int, int]:
  """Returns (width, height) for a given camera."""
  width = int(warp_rc.cam_res.numpy()[cam_id][0])
  height = int(warp_rc.cam_res.numpy()[cam_id][1])
  return width, height


[docs] def get_rgb( rc: 'RenderContextPytree', cam_id: int, rgb_data: jax.Array, ) -> jax.Array: """Unpack uint32 ABGR pixel data into float32 RGB. Args: rc: RenderContextPytree. cam_id: Camera index to extract. rgb_data: Packed render output, shape (..., total_pixels) as uint32. Returns: Float32 RGB array with shape (..., H, W, 3), values in [0, 1]. Any leading batch axes in `rgb_data` are preserved. Raises: RuntimeError: If Warp is not installed. """ if not mjxw.WARP_INSTALLED: raise RuntimeError('Warp not installed.') from mujoco.mjx.warp import render_context # pylint: disable=g-import-not-at-top warp_rc = render_context.get(rc) rgb_adr = int(warp_rc.rgb_adr.numpy()[cam_id]) width, height = _get_camera_resolution(warp_rc, cam_id) packed = jax.lax.dynamic_slice_in_dim( rgb_data, rgb_adr, width * height, axis=rgb_data.ndim - 1 ) b = (packed & 0xFF).astype(jnp.float32) / 255.0 g = ((packed >> 8) & 0xFF).astype(jnp.float32) / 255.0 r = ((packed >> 16) & 0xFF).astype(jnp.float32) / 255.0 rgb = jnp.stack([r, g, b], axis=-1) return rgb.reshape(packed.shape[:-1] + (height, width, 3))
[docs] def get_depth( rc: 'RenderContextPytree', cam_id: int, depth_data: jax.Array, depth_scale: float, ) -> jax.Array: """Extract and normalize depth data for a camera. Args: rc: RenderContextPytree. cam_id: Camera index to extract. depth_data: Raw depth output, shape (..., total_pixels) as float32. depth_scale: Scale factor for normalizing depth values. Returns: Float32 depth array with shape (..., H, W, 1), clamped to [0, 1]. Any leading batch axes in `depth_data` are preserved. Raises: RuntimeError: If Warp is not installed. """ if not mjxw.WARP_INSTALLED: raise RuntimeError('Warp not installed.') from mujoco.mjx.warp import render_context # pylint: disable=g-import-not-at-top warp_rc = render_context.get(rc) depth_adr = int(warp_rc.depth_adr.numpy()[cam_id]) width, height = _get_camera_resolution(warp_rc, cam_id) raw = jax.lax.dynamic_slice_in_dim( depth_data, depth_adr, width * height, axis=depth_data.ndim - 1 ) depth = jnp.clip(raw / depth_scale, 0.0, 1.0) return depth.reshape(raw.shape[:-1] + (height, width, 1))
[docs] def get_segmentation( rc: 'RenderContextPytree', cam_id: int, seg_data: jax.Array, ) -> jax.Array: """Extract segmentation object IDs for a camera. Args: rc: RenderContextPytree. cam_id: Camera index to extract. seg_data: Packed segmentation output, shape (..., total_pixels, 2). Each pixel stores a ``(object_id, object_type)`` pair matching the ``mujoco_warp`` convention. Returns: Integer segmentation array with shape (..., H, W). Each pixel contains the object ID (geom or mesh index, ``-1`` for background). Raises: RuntimeError: If Warp is not installed. ValueError: If segmentation is not enabled for the selected camera. """ if not mjxw.WARP_INSTALLED: raise RuntimeError('Warp not installed.') from mujoco.mjx.warp import render_context # pylint: disable=g-import-not-at-top warp_rc = render_context.get(rc) seg_adr = int(warp_rc.seg_adr.numpy()[cam_id]) if seg_adr < 0: raise ValueError( f'Camera {cam_id} was not configured with segmentation rendering.' ) width, height = _get_camera_resolution(warp_rc, cam_id) # seg_data shape: (..., total_pixels, 2); slice along pixel axis. packed = jax.lax.dynamic_slice_in_dim( seg_data, seg_adr, width * height, axis=seg_data.ndim - 2 ) # Extract object_id (index 0), discard object_type (index 1). return packed[..., 0].reshape(packed.shape[:-2] + (height, width))