Description

• Introduce new unified Viewer class that provides render agnostic way to log simulation data
• Refactor OpenGL viewer code to no longer depend on Warp renderer
• Add support for shadow mapping and basic lighting
• Add Rerun backend
• Add UI frontend for selection API
• Add support for more visual information to the newton.Mesh class (normals, uvs, colors)
• Integrate recording interface

New example in example_viewer.py - basic usage:

while viewer.is_running():

   solver.step(state_in, state_out, control, contacts, dt)

   viewer.begin_frame(t)
   viewer.log_model(state)
   viewer.end_frame()

Todo:

• Update examples to use new Viewer app by default (will come in a separate PR)

Newton Migration Guide

The Viewer class and backends replace the previous warp.sim classes:

• warp.sim.render.SimRenderer → newton.viewer.ViewerBase (interface)
• warp.sim.render.SimRendererOpenGL → newton.viewer.ViewerGL
• warp.sim.render.SimRendererUsd → newton.viewer.ViewerUSD

• The migration guide in docs/migration.rst is up-to date

Before your PR is "Ready for review"

• All commits are signed-off to indicate that your contribution adheres to the Developer Certificate of Origin requirements
• Necessary tests have been added and new examples are tested (see newton/tests/test_examples.py)
• Documentation is up-to-date
• Code passes formatting and linting checks with pre-commit run -a

Summary by CodeRabbit

• New Features

  • Unified viewer with three backends (OpenGL interactive, USD export, Rerun) and a CLI demo.

• Enhancements

  • Interactive UI: ImGui panels, camera controls, file dialogs, FPS/stats overlay, selection/inspection, picking/dragging.
  • Richer rendering: instanced primitives & meshes, per-instance colors/materials, shaders, shadowing, and primitive mesh generators.
  • Mesh format now supports normals, UVs, and per-mesh color.

• Other

  • World-space contact-point computation path removed (may affect contact rendering).