v1.6.0

Changelog

[1.6.0] - 2025-02-03

Added

• Add preview of Tile Cholesky factorization and solve APIs through wp.tile_cholesky(), tile_cholesky_solve()
  and tile_diag_add() (preview APIs are subject to change).
• Support for loading tiles from arrays whose shapes are not multiples of the tile dimensions.
  Out-of-bounds reads will be zero-filled and out-of-bounds writes will be skipped.
• Support for higher-dimensional (up to 4D) tile shapes and memory operations.
• Add intersection-free self-contact support in wp.sim.VDBIntegrator by passing handle_self_contact=True.
  See warp/examples/sim/example_cloth_self_contact.py for a usage example.
• Add functions wp.norm_l1(), wp.norm_l2(), wp.norm_huber(), wp.norm_pseudo_huber(), and wp.smooth_normalize()
  for vector types to a new wp.math module.
• wp.sim.SemiImplicitIntegrator and wp.sim.FeatherstoneIntegrator now have an optional friction_smoothing
  constructor argument (defaults to 1.0) that controls softness of the friction norm computation.
• Support assert statements in kernels (docs).
  Assertions can only be triggered in "debug" mode (GH-366).
• Support CUDA IPC on Linux. Call the ipc_handle() method to get an IPC handle for a wp.Event or a wp.array,
  and call wp.from_ipc_handle() or wp.event_from_ipc_handle() in another process to open the handle
  (docs).
• Add per-module option to disable fused floating point operations, use wp.set_module_options({"fuse_fp": False})
  (GH-379).
• Add per-module option to add CUDA-C line information for profiling, use wp.set_module_options({"lineinfo": True}).
• Support operator overloading for wp.struct objects by defining wp.func functions
  (GH-392).
• Add built-in function wp.len() to retrieve the number of elements for vectors, quaternions, matrices, and arrays
  (GH-389).
• Add warp/examples/optim/example_softbody_properties.py as an optimization example for soft-body properties
  (GH-419).
• Add warp/examples/tile/example_tile_walker.py, which reworks the existing example_walker.py
  to use Warp's tile API for matrix multiplication.
• Add warp/examples/tile/example_tile_nbody.py as an example of an N-body simulation using Warp tile primitives.

Changed

• Breaking: Change wp.tile_load() and wp.tile_store() indexing behavior so that indices are now specified in
  terms of array elements instead of tile multiples.
• Breaking: Tile operations now take shape and offset parameters as tuples,
  e.g.: wp.tile_load(array, shape=(m,n), offset=(i,j)).
• Breaking: Change exception types and error messages thrown by tile functions for improved consistency.
• Add an implicit tile synchronization whenever a shared memory tile's data is reinitialized (e.g. in dynamic loops).
  This could result in lower performance.
• wp.Bvh constructor now supports various construction algorithms via the constructor argument, including
  "sah" (Surface Area Heuristics), "median", and "lbvh" (docs)
• Improve the query efficiency of wp.Bvh and wp.Mesh.
• Improve memory consumption, compilation and runtime performance when using in-place vector/matrix assignments in
  kernels that have enable_backward set to False (GH-332).
• Vector/matrix/quaternion component += and -= operations compile and run faster in the backward pass
  (GH-332).
• Name files in the kernel cache according to their directory. Previously, all files began with
  module_codegen (GH-431).
• Avoid recompilation of modules when changing block_dim.
• wp.autograd.gradcheck_tape() now has additional optional arguments reverse_launches and skip_to_launch_index.
• wp.autograd.gradcheck(), wp.autograd.jacobian(), and wp.autograd.jacobian_fd() now also accept
  arbitrary Python functions that have Warp arrays as inputs and outputs.
• update_vbo_transforms kernel launches in the OpenGL renderer are no longer recorded onto the tape.
• Skip emitting backward functions/kernels in the generated C++/CUDA code when enable_backward is set to False.
• Emit deprecation warnings for the use of the owner and length keywords in the wp.array initializer.
• Emit deprecation warnings for the use of wp.mlp(), wp.matmul(), and wp.batched_matmul().
  Use tile primitives instead.

Fixed

• Fix unintended modification of non-Warp arrays during the backward pass (GH-394).
• Fix so that wp.Tape.zero() zeroes gradients passed via the grads parameter in wp.Tape.backward()
  (GH-407).
• Fix errors during graph capture caused by module unloading (GH-401).
• Fix potential memory corruption errors when allocating arrays with strides (GH-404).
• Fix wp.array() not respecting the target dtype and shape when the given data is an another array with a CUDA interface
  (GH-363).
• Negative constants evaluate to compile-time constants (GH-403)
• Fix ImportError exception being thrown during interpreter shutdown on Windows when using the OpenGL renderer
  (GH-412).
• Fix the OpenGL renderer not working when multiple instances exist at the same time (GH-385).
• Fix AttributeError crash in the OpenGL renderer when moving the camera (GH-426).
• Fix the OpenGL renderer not correctly displaying duplicate capsule, cone, and cylinder shapes
  (GH-388).
• Fix the overriding of wp.sim.ModelBuilder default parameters (GH-429).
• Fix indexing of wp.tile_extract() when the block dimension is smaller than the tile size.
• Fix scale and rotation issues with the rock geometry used in the granular collision SDF example
  (GH-409).
• Fix autodiff Jacobian computation in wp.autograd.jacobian() where in some cases gradients were not zeroed-out properly.
• Fix plotting issues in wp.autograd.jacobian_plot().
• Fix the len() operator returning the total size of a matrix instead of its first dimension.
• Fix gradient instability in rigid-body contact handling for wp.sim.SemiImplicitIntegrator and
  wp.sim.FeatherstoneIntegrator (GH-349).
• Fix overload resolution of generic Warp functions with default arguments.
• Fix rendering of arrows with different up_axis, color in OpenGLRenderer (GH-448).