CHANGELOG.md

Version History

Open VKL 0.13.0

• Driver (now device) API changes:
  • Renamed VKLDriver to VKLDevice and updated associated device setup APIs
  • Use of multiple concurrent devices is now supported; therefore vklNewVolume() and vklNewData() now require a device handle
  • Renamed the ispc_device module and ispc device to cpu_device and cpu, respectively
  • The OPENVKL_CPU_DEVICE_DEFAULT_WIDTH environment variable can now be used to change the cpu device's default SIMD width at run time
• Added new VKLTemporalFormat enum used for temporally varying volume parameterization
• VDB volumes:
  • Support for temporally structured and temporally unstructured (TUV) attribute data, which can be used for motion blurred rendering
  • Supporting tricubic filtering via VKL_FILTER_TRICUBIC filter type
  • Added support for half precision float-point (FP16) attribute data via VKL_HALF data type
  • Added a new InnerNode observer and associated utility functions which allows applications to introspect inner nodes of the internal tree structure, including bounding boxes and value ranges
  • Renamed VKL_FORMAT_CONSTANT_ZYX to VKL_FORMAT_DENSE_ZYX
• Structured regular and spherical volumes:
  • Added support for half precision float-point (FP16) attribute data via VKL_HALF data type
• Unstructured volumes:
  • Added support for elementary cell iteration via the elementaryCellIteration parameter
  • Robustness improvements for hit iteration
• AMR volumes:
  • Improved interval iterator implementation, resolving issues with returned interval nominalDeltaT values
  • Interval iterators now support maxIteratorDepth parameter
• Interval and hit iteration performance improvements when multiple values ranges / values are selected
• Added new temporal compression utilities which applications can use for processing temporally unstructured attribute data
• vklExamples additions demonstrating:
  • Motion blurred rendering on temporally structured and temporally unstructured vdb volumes
  • Tricubic filtering on vdb volumes
  • Half-precision floating-point (FP16) support for structuredRegular, structuredSpherical, and vdb volumes
  • Elementary cell interval iteration on unstructured volumes
  • Use of the InnerNode observer on vdb volumes
• Superbuild updates to:
  • Embree 3.13.0
  • rkcommon 1.6.1
• Minimum rkcommon version is now 1.6.1

Open VKL 0.12.1

• Fixed bug in VDB volume interval iterator implementation which could lead to missed intervals or incorrect value ranges in returned intervals

Open VKL 0.12.0

• Added support for temporally varying volumes with associated API changes for sampling, gradients, and hit iteration. This feature can be used to enable motion blurred rendering
• Structured regular volumes:
  • Support for temporally structured and temporally unstructured (TUV) input data
  • Improved nominalDeltaT for interval iteration
  • Interval iterator robustness improvements for axis-aligned rays
  • Sampling performance improvements
• VDB volumes:
  • Multi-attribute support (including three-component float grids)
  • Interval iterator robustness improvements for axis-aligned rays
  • Performance improvements for scalar sampling
  • Now restricting volumes to exactly four levels
  • Allowing leaf nodes on the lowest level only
• Unstructured volumes:
  • Improved nominalDeltaT for interval iteration
• vdb_util updates:
  • Support for loading multi-attribute .vdb files (float and Vec3s grids)
  • Fix order of rotation matrix coefficients loaded from .vdb files
• vklExamples additions demonstrating:
  • Motion blurred rendering on temporally structured and temporally unstructured volumes (structuredRegular only)
  • Support for vdb multi-attribute volumes
  • Hit iterator time support
• Superbuild updates to:
  • Embree 3.12.2
  • rkcommon 1.6.0
  • ISPC 1.15.0
  • OpenVDB 8.0.0
• Minimum rkcommon version is now 1.6.0

Open VKL 0.11.0

• Introduced API support for multi-attribute volumes, including APIs for sampling multiple attributes simultaneously
  • Initially only structuredRegular and structuredSpherical volume types support multi-attribute data
• Iterator APIs now work on sampler objects rather than volumes, supporting finer-grained configurability
• Observers can now be created for both volume and sampler objects
  • LeafNodeAccess observers must now be created on sampler objects
• Log and error callbacks now support a user pointer
• vdb volume interval iterators:
  • Added support for elementary cell iteration when maxIteratorDepth is set to VKL_VDB_NUM_LEVELS-1
  • Up to 2x faster iteration
• unstructured and particle volume interval iterators:
  • Improved interior empty space skipping behavior
  • Added support for configurable iterator depth via the maxIteratorDepth parameter
• Added support for filter modes in structuredRegular and structuredSpherical volumes
• amr volumes now support method parameter on sampler objects
• Added new interval_iterator_debug renderer in vklExamples to visualize interval iteration behavior
• Hit iterator accuracy improvements for unstructured volumes
• Fixed bugs in amr and vdb volume bounding box computations
• Fixed bug in unstructured volume gradient computations near empty regions
• Minimum ISPC version is now v1.14.1

Open VKL 0.10.0 (alpha)

• Added new particle volume type supporting Gaussian radial basis functions
• Introduced VKLSampler objects allowing configuration of sampling and gradient behavior
• Added stream-wide sampling and gradient APIs
• Introduced a new way to allocate iterators, giving the user more freedom in choosing allocation schemes and reducing iterator size
• Added support for strided data arrays
• Added gradient implementations for amr and vdb volumes
• Hit iterator accuracy improvements for amr, structuredSpherical, unstructured, and vdb volumes
• Up to 4x performance improvement for structuredRegular and structuredSpherical sampling for volumes in the 1-2GB range
• Up to 2x performance improvement for structuredRegular interval iteration
• Improved commit speed for unstructured volumes
• Improved value range computation in vdb volumes
• Improved isosurface shading in vklExamples
• Improved parameter validation across all volume types
• Aligned VKLHit[4,8,16] and VKLInterval[4,8,16] structs
• Added hit epsilon to VKLHit[4,8,16]
• Updated parameter names for vdb volumes
• Renamed VKLVdbLeafFormat to VKLFormat
• Fixed incorrect use of system-installed CMake in superbuild while building dependencies
• Fixed various memory leaks
• Fixed crashes which could occur in VdbVolume::cleanup() and vklShutdown()
• Moved from ospcommon to rkcommon v1.4.1

Open VKL 0.9.0 (alpha)

• Added support for VDB sparse structured volumes ("vdb" volume type)
• Added vdb_util library to simplify instantiation of VDB volumes, and support loading of .vdb files using OpenVDB
• Added VKLObserver and associated APIs, which may used by volume types to pass information back to the application
  • A LeafNodeAccess observer is provided for VDB volumes to support on-demand loading of leaf nodes
• Structured regular volumes:
  • Up to 6x performance improvement for scalar iterator initialization
  • Up to 2x performance improvement for scalar iterator iteration
• General improvements to the CMake Superbuild for building Open VKL and all associated dependencies
• Allowing instantiation of ISPC driver for any supported SIMD width (in addition to the default automatically selected width)
• Volume type names are now camelCase (legacy snake_case type names are deprecated), impacting structuredRegular and structuredSpherical volumes
• Enabling flushDenormals driver mode by default
• Aligning public vkl_vvec3f[4,8,16] and vkl_vrange1f[4,8,16] types
• Added VKL_LOG_NONE log level
• Fixed bug in vklExamples which could lead to improper rendering on macOS Catalina
• Fixed bug in unstructured volume interval iterator which could lead to errors with some combinations of lane masks
• Now providing binary releases for Linux, macOS, and Windows

Open VKL 0.8.0 (alpha)

• Added support for structured volumes on spherical grids ("structured_spherical" volume type)
• Structured regular volumes:
  • Up to 8x performance improvement for scalar (single-wide) sampling
  • Fixed hit iterator bug which could lead to isosurfacing artifacts
  • Renamed voxelData parameter to data
• Unstructured volumes:
  • Up to 4x performance improvement for scalar (single-wide) sampling
  • Improved interval iterator implementation for more efficient space skipping and tighter value bounds on returned intervals
  • Now using Embree for BVH builds for faster build times / volume commits
  • Renamed vertex.value and cell.value parameters to vertex.data and cell.data, respectively
• AMR volumes:
  • renamed block.cellWidth parameter to cellWidth, and clarified API documentation
• Added vklGetValueRange() API for querying volume value ranges
• Added new driver parameters, APIs, and environment variables allowing user control of log levels, log / error output redirection, number of threads, and other options
• vklIterateHit[4,8,16]() and vklIterateInterval[4,8,16]() calls now only populate hit / interval data for active lanes
• Changed VKLDataType enum values for better forward compatibility
• ISPC-side hit and interval iterator objects must now be declared varying
• More flexible ISA build configuration through OPENVKL_MAX_ISA and OPENVKL_ISA_* CMake build options
• Minimum ospcommon version is now 1.1.0

Open VKL 0.7.0 (alpha)

• Initial public alpha release, with support for structured, unstructured, and AMR volumes.