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Intel^® OSPRay

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OSPRay Overview

Intel OSPRay is an open source, scalable, and portable ray tracing engine for high-performance, high-fidelity visualization on Intel Architecture CPUs. OSPRay is part of the Intel oneAPI Rendering Toolkit and is released under the permissive Apache 2.0 license.

The purpose of OSPRay is to provide an open, powerful, and easy-to-use rendering library that allows one to easily build applications that use ray tracing based rendering for interactive applications (including both surface- and volume-based visualizations). OSPRay is completely CPU-based, and runs on anything from laptops, to workstations, to compute nodes in HPC systems.

OSPRay internally builds on top of Intel Embree and ISPC (Intel SPMD Program Compiler), and fully exploits modern instruction sets like Intel SSE4, AVX, AVX2, and AVX-512 to achieve high rendering performance, thus a CPU with support for at least SSE4.1 is required to run OSPRay.

OSPRay Support and Contact

OSPRay is under active development, and though we do our best to guarantee stable release versions a certain number of bugs, as-yet-missing features, inconsistencies, or any other issues are still possible. Should you find any such issues please report them immediately via OSPRay’s GitHub Issue Tracker (or, if you should happen to have a fix for it,you can also send us a pull request); for missing features please contact us via email at ospray@googlegroups.com.

Join our mailing list to receive release announcements and major news regarding OSPRay.

Version History

Changes in v2.0.1:

• Fix bug where Embree user-defined geometries were not indexed correctly in the scene, which now requires Embree v3.8.0+
• Fix crash when the path tracer encounters geometric models that do not have a material
• Fix crash when some path tracer materials generated NULL bsdfs
• Fix bug where ospGetBounds returned incorrect values
• Fix missing symbol in denoiser module
• Fix missing symbol exports on Windows for all OSPRay built modules
• Add the option to specify a single color for geometric models
• The scivis renderer now respects the opacity component of color on geometric models
• Fix various inconsistent handling of frame buffer alpha between renderers
• ospGetCurrentDevice now increments the ref count of the returned OSPDevice handle, so applications will need to release the handle when finished by using ospDeviceRelease accordingly
• Added denoiser to ospExamples app
• Added module_mpi to superbuild (disabled by default)
• The superbuild now will emit a CMake error when using any 32-bit CMake generator, as 32-bit builds are not supported

Changes in v2.0.0:

• New major revision of OSPRay brings API breaking improvements over v1.x. See doc/ospray2_porting_guide.md for a deeper description of migrating from v1.x to v2.0 and the latest API documentation
  • ospRenderFrame now takes all participating objects as function parameters instead of setting some as renderer params
  • ospRenderFrame is now asynchronous, where the task is managed through a returned OSPFuture handle
  • The heirarchy of objets in a scene are now more granular to aid in scene construction flexibility and reduce potential object duplication
  • Type-specific parameter setting functions have been consolidated into a single ospSetParam API call
  • C++ wrappers found in ospray_cpp.h now automatically track handle lifetimes, therefore applications using them do not need to use ospRelease (or the new ospRetain) with them: see usage example in apps/tutorials/ospTutorial.cpp
  • Unused parameters are reported as status messages when logLevel is at least warning (most easily set by enabling OSPRay debug on initialization)
• New utility library which adds functions to help with new API migration and reduction of boilerplate code
  • Use ospray_util.h to access these additional functions
  • All utility functions are implemented in terms of the core API found in ospray.h, therefore they are compatible with any device backend
• Introduction of new Intel® Open Volume Kernel Library (Open VKL) for greatly enhanced volume sampling and rendering features and performance
• Added direct support for Intel® Open Image Denoise as an optional module, which adds a denoiser type to ospNewImageOperation
• OSPRay now requires minimum Embree v3.7.0
• New CMake superbuild available to build both OSPRay’s dependencies and OSPRay itself
  • Found in scripts/superbuild
  • See documentation for more details and example usage
• The ospcommon library now lives as a stand alone repository and is required to build OSPRay
• The MPI module is now a separate repository, which also contains all MPI distributed rendering documentation
• Log levels are now controled with enums and named strings (where applicable)
  • A new flag was also introduced which turns all OSP_LOG_WARNING messages into errors, which are submitted to the error callback instead of the message callback
  • Any unused parameters an object ignores now emit a warning message
• New support for volumes in the pathtracer
  • Several parameters are available for performance/quality trade-offs for both photo-realistic and scientific visualization use cases
• Simplification of the SciVis renderer
  • Fixed AO lighting and simple ray marched volume rendering for ease of use and performance
• Overlapping volumes are now supported in both the pathtracer and scivis renderers
• New API call for querying the bounds of objects (OSPWorld, OSPInstance, and OSPGroup)
• Lights now exist as a parameter to the world instead of the renderer
• Removal of slices geometry. Instead, any geometry with volume texture can be used for slicing
• Introduction of new boxes geometry type
• Expansion of information returned by ospPick
• Addition of API to query version information at runtime
• Curves now supports both, per vertex varying radii as in vec4f[] vertex.position_radius and constant radius for the geometry with float radius. It uses OSP_ROUND type and OSP_LINEAR basis by default to create the connected segments of constant radius. For per vertex varying radii curves it uses Embree curves.
• Add new Embree curve type OSP_CATMULL_ROM for curves
• Minimum required Embree version is now 3.7.0
• Removal of cylinders and streamlines geometry, use curves instead
• Triangle mesh and Quad mesh are superseded by the mesh geometry
• Applications need to use the various error reporting methods to check wether the creation (via ospNew...) of objects failed; a returned NULL is not a special handle anymore to signify an error
• Changed module init methods to facilitate version checking: extern "C" OSPError ospray_module_init_<name>(int16_t versionMajor, int16_t versionMinor, int16_t versionPatch)
• The map_backplate texture is supported in all renderers and does not hide lights in infinity (like the HDRI light) anymore; explicitely make lights invisible if this is needed
• Changed the computation of variance for adaptive accumulation to be independent of TILE_SIZE, thus varianceThreshold needs to be adapted if using a different TILE_SIZE than default 64
• OSPGeometricModel now has the option to index a renderer-global material list that lives on the renderer, allowing scenes to avoid renderer-specific materials
• Object type names and parameters all now follow the camel-case convention
• New ospExamples app which consolidates previous interactive apps into one
• New ospBenchmark app which implements a runnable benchmark suite
• Known issues:
  • ISPC v1.11.0 and Embree v3.6.0 are both incompatible with OSPRay and should be avoided (OSPRay should catch this during CMake configure)

Changes in v1.8.5:

• Fix float precision cornercase (NaNs) in sphere light sampling
• Fix CMake bug that assumed .git was a directory, which is not true when using OSPRay as a git submodule
• Fix CMake warning
• Fix DLL_EXPORT issue with ospray_testing helper library on Windows

Changes in v1.8.4:

• Add location of libospray to paths searched to find modules

Changes in v1.8.3:

• Fix bug where parameters set by ospSet1b() were being ignored
• Fix bug in box intersection tests possibly creating NaNs
• Fix issue with client applications calling find_package(ospray) more than once
• Fix bug in cylinder intersection when ray and cylinder are perpendicular
• Fix rare crash in path tracer / MultiBSDF

Changes in v1.8.2:

• CMake bug fix where external users of OSPRay needed CMake newer than version 3.1
• Fix incorrect propagation of tasking system flags from an OSPRay install
• Fix inconsistency between supported environment variables and command line parameters passed to ospInit()
  • Missing variables were OSPRAY_LOAD_MODULES and OSPRAY_DEFAULT_DEVICE

Changes in v1.8.1:

• CMake bug fix to remove full paths to dependencies in packages

Changes in v1.8.0:

• This will be the last minor revision of OSPRay. Future development effort in the devel branch will be dedicated to v2.0 API changes and may break existing v1.x applications.
  • This will also be the last version of OSPRay to include ospray_sg and the Example Viewer. Users which depend on these should instead use the separate OSPRay Studio project, where ospray_sg will be migrated.
  • We will continue to support patch releases of v1.8.x in case of any reported bugs
• Refactored CMake to use newer CMake concepts
  • All targets are now exported in OSPRay installs and can be consumed by client projects with associated includes, libraries, and definitions
  • OSPRay now requires CMake v3.1 to build
  • See documentation for more details
• Added new minimal tutorial apps to replace the more complex Example Viewer
• Added new “subdivision” geometry type to support subdivision surfaces
• Added support for texture formats L8, LA8 (gamma-encoded luminance), and RA8 (linear two component). Note that the enum OSP_TEXTURE_FORMAT_INVALID changed its value, thus recompilation may be necessary.
• Automatic epsilon handling, which removes the “epsilon” parameter on all renderers
• Normals in framebuffer channel OSP_FB_NORMAL are now in world-space
• Added support for Intel® Open Image Denoise to the Example Viewer
  • This same integration will soon be ported to OSPRay Studio
• Fixed artifacts for scaled instances of spheres, cylinders and streamlines
• Improvements to precision of intersections with cylinders and streamlines
• Fixed Quadlight: the emitting side is now indeed in direction edge1×edge2

Changes in v1.7.3:

• Make sure a “default” device can always be created
• Fixed ospNewTexture2D (completely implementing old behavior)
• Cleanup any shared object handles from the OS created from ospLoadModule()

Changes in v1.7.2:

• Fixed issue in mpi_offload device where ospRelease would sometimes not correctly free objects
• Fixed issue in ospray_sg where structured volumes would not properly release the underlying OSPRay object handles

Changes in v1.7.1:

• Fixed issue where the Principled material would sometimes show up incorrectly as black
• Fixed issue where some headers were missing from install packages

Changes in v1.7.0:

• Generalized texture interface to support more than classic 2D image textures, thus OSPTexture2D and ospNewTexture2D are now deprecated, use the new API call ospNewTexture("texture2d") instead
  • Added new volume texture type to visualize volume data on arbitrary geometry placed inside the volume
• Added new framebuffer channels OSP_FB_NORMAL and OSP_FB_ALBEDO
• Applications can get information about the progress of rendering the current frame, and optionally cancel it, by registering a callback function via ospSetProgressFunc()
• Lights are not tied to the renderer type, so a new function ospNewLight3() was introduced to implement this. Please convert all uses of ospNewLight() and/or ospNewLight2() to ospNewLight3()
• Added sheenTint parameter to Principled material
• Added baseNormal parameter to Principled material
• Added low-discrepancy sampling to path tracer
• The spp parameter on the renderer no longer supports values less than 1, instead applications should render to a separate, lower resolution framebuffer during interaction to achieve the same behavior

Changes in v1.6.1:

• Many bug fixes
  • Quad mesh interpolation and sampling
  • Normal mapping in path tracer materials
  • Memory corruption with partly emitting mesh lights
  • Logic for setting thread affinity

Changes in v1.6.0:

• Updated ispc device to use Embree3 (minimum required Embree version is 3.1)
• Added new ospShutdown() API function to aid in correctness and determinism of OSPRay API cleanup
• Added “Principled” and "CarPaint" materials to the path tracer
• Improved flexibility of the tone mapper
• Improvements to unstructured volume
  • Support for wedges (in addition to tets and hexes)
  • Support for implicit isosurface geometry
  • Support for cell-centered data (as an alternative to per-vertex data)
  • Added an option to precompute normals, providing a memory/performance trade-off for applications
• Implemented “quads” geometry type to handle quads directly
• Implemented the ability to set “void” cell values in all volume types: when NaN is present as a volume’s cell value the volume sample will be ignored by the SciVis renderer
• Fixed support for color strides which were not multiples of sizeof(float)
• Added support for RGBA8 color format to spheres, which can be set by specifying the “color_format” parameter as OSP_UCHAR4, or passing the “color” array through an OSPData of type OSP_UCHAR4.
• Added ability to configure Embree scene flags via OSPModel parameters
• ospFreeFrameBuffer() has been deprecated in favor of using ospRelease() to free framebuffer handles
• Fixed memory leak caused by incorrect parameter reference counts in ispc device
• Fixed occasional crashes in the mpi_offload device on shutdown
• Various improvements to sample apps and ospray_sg
  • Added new generator nodes, allowing the ability to inject programmatically generated scene data (only C++ for now)
  • Bug fixes and improvements to enhance stability and usability

Changes in v1.5.0:

• Unstructured tetrahedral volume now generalized to also support hexahedral data, now called unstructured_volume
• New function for creating materials (ospNewMaterial2()) which takes the renderer type string, not a renderer instance (the old version is now deprecated)
• New tonemapper PixelOp for tone mapping final frames
• Streamlines now support per-vertex radii and smooth interpolation
• ospray_sg headers are now installed alongside the SDK
• Core OSPRay ispc device now implemented as a module
  • Devices which implement the public API are no longer required to link the dependencies to core OSPRay (e.g., Embree v2.x)
  • By default, ospInit() will load the ispc module if a device was not created via --osp:mpi or --osp:device:[name]
• MPI devices can now accept an existing world communicator instead of always creating their own
• Added ability to control ISPC specific optimization flags via CMake options. See the various ISPC_FLAGS_* variables to control which flags get used
• Enhancements to sample applications
  • ospray_sg (and thus ospExampleViewer/ospBenchmark) can now be extended with new scene data importers via modules or the SDK
  • Updated ospTutorial examples to properly call ospRelease()
  • New options in the ospExampleViewer GUI to showcase new features (sRGB framebuffers, tone mapping, etc.)
• General bug fixes
  • Fixes to geometries with multiple emissive materials
  • Improvements to precision of ray-sphere intersections

Changes in v1.4.3:

• Several bug fixes
  • Fixed potential issue with static initialization order
  • Correct compiler flags for Debug config
  • Spheres postIntersect shading is now 64-bit safer

Changes in v1.4.2:

• Several cleanups and bug fixes
  • Fixed memory leak where the Embree BVH was never released when an OSPModel was released
  • Fixed a crash when API logging was enabled in certain situations
  • Fixed a crash in MPI mode when creating lights without a renderer
  • Fixed an issue with camera lens samples not initialized when spp <= 0
  • Fixed an issue in ospExampleViewer when specifying multiple data files
• The C99 tutorial is now indicated as the default; the C++ wrappers do not change the semantics of the API (memory management) so the C99 version should be considered first when learning the API

Changes in v1.4.1:

• Several cleanups and bug fixes
  • Improved precision of ray intersection with streamlines, spheres, and cylinder geometries
  • Fixed address overflow in framebuffer, in practice image size is now limited only by available memory
  • Fixed several deadlocks and race conditions
  • Fix shadow computation in SciVis renderer, objects behind light sources do not occlude anymore
  • No more image jittering with MPI rendering when no accumulation buffer is used
• Improved path tracer materials
  • Additionally support RGB eta/k for Metal
  • Added Alloy material, a “metal” with textured color
• Minimum required Embree version is now v2.15

Changes in v1.4.0:

• New adaptive mesh refinement (AMR) and unstructured tetrahedral volume types
• Dynamic load balancing is now implemented for the mpi_offload device
• Many improvements and fixes to the available path tracer materials
  • Specular lobe of OBJMaterial uses Blinn-Phong for more realistic highlights
  • Metal accepts spectral samples of complex refraction index
  • ThinGlass behaves consistent to Glass and can texture attenuation color
• Added Russian roulette termination to path tracer
• SciVis OBJMaterial accepts texture coordinate transformations
• Applications can now access depth information in MPI distributed uses of OSPRay (both mpi_offload and mpi_distributed devices)
• Many robustness fixes for both the mpi_offload and mpi_distributed devices through improvements to the mpi_common and mpi_maml infrastructure libraries
• Major sample app cleanups
  • ospray_sg library is the new basis for building apps, which is a scene graph implementation
  • Old (unused) libraries have been removed: miniSG, command line, importer, loaders, and scripting
  • Some removed functionality (such as scripting) may be reintroduced in the new infrastructure later, though most features have remained and have been improved
  • Optional improved texture loading has been transitioned from ImageMagick to OpenImageIO
• Many cleanups, bug fixes, and improvements to ospray_common and other support libraries
• This will be the last release in which we support MSVC12 (Visual Studio 2013). Future releases will require VS2015 or newer

Changes in v1.3.1:

• Improved robustness of OSPRay CMake find_package config
  • Fixed bugs related to CMake configuration when using the OSPRay SDK from an install
• Fixed issue with Embree library when installing with OSPRAY_INSTALL_DEPENDENCIES enabled

Changes in v1.3.0:

• New MPI distributed device to support MPI distributed applications using OSPRay collectively for “in-situ” rendering (currently in “alpha”)
  • Enabled via new mpi_distributed device type
  • Currently only supports raycast renderer, other renderers will be supported in the future
  • All API calls are expected to be exactly replicated (object instances and parameters) except scene data (geometries and volumes)
  • The original MPI device is now called the mpi_offload device to differentiate between the two implementations
• Support of Intel® AVX-512 for next generation Intel® Xeon® processor (codename Skylake), thus new minimum ISPC version is 1.9.1
• Thread affinity of OSPRay’s tasking system can now be controlled via either device parameter setAffinity, or command line parameter osp:setaffinity, or environment variable OSPRAY_SET_AFFINITY
• Changed behavior of the background color in the SciVis renderer: bgColor now includes alpha and is always blended (no backgroundEnabled anymore). To disable the background do not set bgColor, or set it to transparent black (0, 0, 0, 0)
• Geometries “spheres” and “cylinders” now support texture coordinates
• The GLUT- and Qt-based demo viewer applications have been replaced by an example viewer with minimal dependencies
  • Building the sample applications now requires GCC 4.9 (previously 4.8) for features used in the C++ standard library; OSPRay itself can still be built with GCC 4.8
  • The new example viewer based on ospray::sg (called ospExampleViewerSg) is the single application we are consolidating to, ospExampleViewer will remain only as a deprecated viewer for compatibility with the old ospGlutViewer application
• Deprecated ospCreateDevice(); use ospNewDevice() instead
• Improved error handling
  • Various API functions now return an OSPError value
  • ospDeviceSetStatusFunc() replaces the deprecated ospDeviceSetErrorMsgFunc()
  • New API functions to query the last error (ospDeviceGetLastErrorCode() and ospDeviceGetLastErrorMsg()) or to register an error callback with ospDeviceSetErrorFunc()
  • Fixed bug where exceptions could leak to C applications

Changes in v1.2.1:

• Various bug fixes related to MPI distributed rendering, ISPC issues on Windows, and other build related issues

Changes in v1.2.0:

• Added support for volumes with voxelType short (16-bit signed integers). Applications need to recompile, because OSPDataType has been re-enumerated
• Removed SciVis renderer parameter aoWeight, the intensity (and now color as well) of AO is controlled via “ambient” lights. If aoSamples is zero (the default) then ambient lights cause ambient illumination (without occlusion)
• New SciVis renderer parameter aoTransparencyEnabled, controlling whether object transparency is respected when computing ambient occlusion (disabled by default, as it is considerable slower)
• Implement normal mapping for SciVis renderer
• Support of emissive (and illuminating) geometries in the path tracer via new material “Luminous”
• Lights can optionally made invisible by using the new parameter isVisible (only relevant for path tracer)
• OSPRay Devices are now extendable through modules and the SDK
  • Devices can be created and set current, creating an alternative method for initializing the API
  • New API functions for committing parameters on Devices
• Removed support for the first generation Intel® Xeon Phi™ coprocessor (codename Knights Corner)
• Other minor improvements, updates, and bug fixes
  • Updated Embree required version to v2.13.0 for added features and performance
  • New API function ospDeviceSetErrorMsgFunc() to specify a callback for handling message outputs from OSPRay
  • Added ability to remove user set parameter values with new ospRemoveParam() API function
  • The MPI device is now provided via a module, removing the need for having separately compiled versions of OSPRay with and without MPI
  • OSPRay build dependencies now only get installed if OSPRAY_INSTALL_DEPENDENCIES CMake variable is enabled

Changes in v1.1.2:

• Various bug fixes related to normalization, epsilons and debug messages

Changes in v1.1.1:

• Fixed support of first generation Intel Xeon Phi coprocessor (codename Knights Corner) and the COI device
• Fix normalization bug that caused rendering artifacts

Changes in v1.1.0:

• New “scivis” renderer features
  • Single sided lighting (enabled by default)
  • Many new volume rendering specific features
    • Adaptive sampling to help improve the correctness of rendering high-frequency volume data
    • Pre-integration of transfer function for higher fidelity images
    • Ambient occlusion
    • Volumes can cast shadows
    • Smooth shading in volumes
    • Single shading point option for accelerated shading
• Added preliminary support for adaptive accumulation in the MPI device
• Camera specific features
  • Initial support for stereo rendering with the perspective camera
  • Option architectural in perspective camera, rectifying vertical edges to appear parallel
  • Rendering a subsection of the full view with imageStart/imageEnd supported by all cameras
• This will be our last release supporting the first generation Intel Xeon Phi coprocessor (codename Knights Corner)
  • Future major and minor releases will be upgraded to the latest version of Embree, which no longer supports Knights Corner
  • Depending on user feedback, patch releases are still made to fix bugs
• Enhanced output statistics in ospBenchmark application
• Many fixes to the OSPRay SDK
  • Improved CMake detection of compile-time enabled features
  • Now distribute OSPRay configuration and ISPC CMake macros
  • Improved SDK support on Windows
• OSPRay library can now be compiled with -Wall and -Wextra enabled
  • Tested with GCC v5.3.1 and Clang v3.8
  • Sample applications and modules have not been fixed yet, thus applications which build OSPRay as a CMake subproject should disable them with -DOSPRAY_ENABLE_APPS=OFF and -DOSPRAY_ENABLE_MODULES=OFF
• Minor bug fixes, improvements, and cleanups
  • Regard shading normal when bump mapping
  • Fix internal CMake naming inconsistencies in macros
  • Fix missing API calls in C++ wrapper classes
  • Fix crashes on MIC
  • Fix thread count initialization bug with TBB
  • CMake optimizations for faster configuration times
  • Enhanced support for scripting in both ospGlutViewer and ospBenchmark applications

Changes in v1.0.0:

• New OSPRay SDK
  • OSPRay internal headers are now installed, enabling applications to extend OSPRay from a binary install
  • CMake macros for OSPRay and ISPC configuration now a part of binary releases
    • CMake clients use them by calling include(${OSPRAY_USE_FILE}) in their CMake code after calling find_package(ospray)
  • New OSPRay C++ wrapper classes
    • These act as a thin layer on top of OSPRay object handles, where multiple wrappers will share the same underlying handle when assigned, copied, or moved
    • New OSPRay objects are only created when a class instance is explicitly constructed
    • C++ users are encouraged to use these over the ospray.h API
• Complete rework of sample applications
  • New shared code for parsing the commandline
  • Save/load of transfer functions now handled through a separate library which does not depend on Qt
  • Added ospCvtParaViewTfcn utility, which enables ospVolumeViewer to load color maps from ParaView
  • GLUT based sample viewer updates
    • Rename of ospModelViewer to ospGlutViewer
    • GLUT viewer now supports volume rendering
    • Command mode with preliminary scripting capabilities, enabled by pressing ‘:’ key (not available when using Intel C++ Compiler (icc))
  • Enhanced support of sample applications on Windows
• New minimum ISPC version is 1.9.0
• Support of Intel® AVX-512 for second generation Intel Xeon Phi processor (codename Knights Landing) is now a part of the OSPRAY_BUILD_ISA CMake build configuration
  • Compiling AVX-512 requires icc to be enabled as a build option
• Enhanced error messages when ospLoadModule() fails
• Added OSP_FB_RGBA32F support in the DistributedFrameBuffer
• Updated Glass shader in the path tracer
• Many miscellaneous cleanups, bug fixes, and improvements

Changes in v0.10.1:

• Fixed support of first generation Intel Xeon Phi coprocessor (codename Knights Corner)
• Restored missing implementation of ospRemoveVolume()

Changes in v0.10.0:

• Added new tasking options: Cilk, Internal, and Debug
  • Provides more ways for OSPRay to interact with calling application tasking systems
    • Cilk: Use Intel® Cilk™ Plus language extensions (icc only)
    • Internal: Use hand written OSPRay tasking system
    • Debug: All tasks are run in serial (useful for debugging)
  • In most cases, Intel Threading Building Blocks (Intel TBB) remains the fastest option
• Added support for adaptive accumulation and stopping
  • ospRenderFrame now returns an estimation of the variance in the rendered image if the framebuffer was created with the OSP_FB_VARIANCE channel
  • If the renderer parameter varianceThreshold is set, progressive refinement concentrates on regions of the image with a variance higher than this threshold
• Added support for volumes with voxelType ushort (16-bit unsigned integers)
• OSPTexture2D now supports sRGB formats – actually most images are stored in sRGB. As a consequence the API call ospNewTexture2D() needed to change to accept the new OSPTextureFormat parameter
• Similarly, OSPRay’s framebuffer types now also distinguishes between linear and sRGB 8-bit formats. The new types are OSP_FB_NONE, OSP_FB_RGBA8, OSP_FB_SRGBA, and OSP_FB_RGBA32F
• Changed “scivis” renderer parameter defaults
  • All shading (AO + shadows) must be explicitly enabled
• OSPRay can now use a newer, pre-installed Embree enabled by the new OSPRAY_USE_EXTERNAL_EMBREE CMake option
• New ospcommon library used to separately provide math types and OS abstractions for both OSPRay and sample applications
  • Removes extra dependencies on internal Embree math types and utility functions
  • ospray.h header is now C99 compatible
• Removed loaders module, functionality remains inside of ospVolumeViewer
• Many miscellaneous cleanups, bug fixes, and improvements
  • Fixed data distributed volume rendering bugs when using less blocks than workers
  • Fixes to CMake find_package() config
  • Fix bug in GhostBlockBrickVolume when using doubles
  • Various robustness changes made in CMake to make it easier to compile OSPRay

Changes in v0.9.1:

• Volume rendering now integrated into the “scivis” renderer
  • Volumes are rendered in the same way the “dvr” volume renderer renders them
  • Ambient occlusion works with implicit isosurfaces, with a known visual quality/performance trade-off
• Intel Xeon Phi coprocessor (codename Knights Corner) COI device and build infrastructure restored (volume rendering is known to still be broken)
• New support for CPack built OSPRay binary redistributable packages
• Added support for HDRI lighting in path tracer
• Added ospRemoveVolume() API call
• Added ability to render a subsection of the full view into the entire framebuffer in the perspective camera
• Many miscellaneous cleanups, bug fixes, and improvements
  • The depthbuffer is now correctly populated by in the “scivis” renderer
  • Updated default renderer to be “ao1” in ospModelViewer
  • Trianglemesh postIntersect shading is now 64-bit safe
  • Texture2D has been reworked, with many improvements and bug fixes
  • Fixed bug where MPI device would freeze while rendering frames with Intel TBB
  • Updates to CMake with better error messages when Intel TBB is missing

Changes in v0.9.0:

The OSPRay v0.9.0 release adds significant new features as well as API changes.

• Experimental support for data-distributed MPI-parallel volume rendering
• New SciVis-focused renderer (“raytracer” or “scivis”) combining functionality of “obj” and “ao” renderers
  • Ambient occlusion is quite flexible: dynamic number of samples, maximum ray distance, and weight
• Updated Embree version to v2.7.1 with native support for Intel AVX-512 for triangle mesh surface rendering on the Intel Xeon Phi processor (codename Knights Landing)
• OSPRay now uses C++11 features, requiring up to date compiler and standard library versions (GCC v4.8.0)
• Optimization of volume sampling resulting in volume rendering speedups of up to 1.5×
• Updates to path tracer
  • Reworked material system
  • Added texture transformations and colored transparency in OBJ material
  • Support for alpha and depth components of framebuffer
• Added thinlens camera, i.e., support for depth of field
• Tasking system has been updated to use Intel Threading Building Blocks (Intel TBB)
• The ospGet*() API calls have been deprecated and will be removed in a subsequent release

Changes in v0.8.3:

• Enhancements and optimizations to path tracer
  • Soft shadows (light sources: sphere, cone, extended spot, quad)
  • Transparent shadows
  • Normal mapping (OBJ material)
• Volume rendering enhancements
  • Expanded material support
  • Support for multiple lights
  • Support for double precision volumes
  • Added ospSampleVolume() API call to support limited probing of volume values
• New features to support compositing externally rendered content with OSPRay-rendered content
  • Renderers support early ray termination through a maximum depth parameter
  • New OpenGL utility module to convert between OSPRay and OpenGL depth values
• Added panoramic and orthographic camera types
• Proper CMake-based installation of OSPRay and CMake find_package() support for use in external projects
• Experimental Windows support
• Deprecated ospNewTriangleMesh(); use ospNewGeometry("triangles") instead
• Bug fixes and cleanups throughout the codebase

Changes in v0.8.2:

• Initial support for Intel AVX-512 and the Intel Xeon Phi processor (codename Knights Landing)
• Performance improvements to the volume renderer
• Incorporated implicit slices and isosurfaces of volumes as core geometry types
• Added support for multiple disjoint volumes to the volume renderer
• Improved performance of ospSetRegion(), reducing volume load times
• Improved large data handling for the shared_structured_volume and block_bricked_volume volume types
• Added support for DDS horizon data to the seismic module
• Initial support in the Qt viewer for volume rendering
• Updated to ISPC 1.8.2
• Various bug fixes, cleanups and documentation updates throughout the codebase

Changes in v0.8.1:

• The volume renderer and volume viewer can now be run MPI parallel (data replicated) using the --osp:mpi command line option
• Improved performance of volume grid accelerator generation, reducing load times for large volumes
• The volume renderer and volume viewer now properly handle multiple isosurfaces
• Added small example tutorial demonstrating how to use OSPRay
• Several fixes to support older versions of GCC
• Bug fixes to ospSetRegion() implementation for arbitrarily shaped regions and setting large volumes in a single call
• Bug fix for geometries with invalid bounds; fixes streamline and sphere rendering in some scenes
• Fixed bug in depth buffer generation

Changes in v0.8.0:

• Incorporated early version of a new Qt-based viewer to eventually unify (and replace) the existing simpler GLUT-based viewers
• Added new path tracing renderer (ospray/render/pathtracer),
• roughly based on the Embree sample path tracer
• Added new features to the volume renderer
  • Gradient shading (lighting)
  • Implicit isosurfacing
  • Progressive refinement
  • Support for regular grids, specified with the gridOrigin and gridSpacing parameters
  • New shared_structured_volume volume type that allows voxel data to be provided by applications through a shared data buffer
  • New API call to set (sub-)regions of volume data (ospSetRegion())
• Added a subsampling-mode, enabled with a negative spp parameter; the first frame after scene changes is rendered with reduced resolution, increasing interactivity
• Added multi-target ISA support: OSPRay will now select the appropriate ISA at runtime
• Added support for the Stanford SEP file format to the seismic module
• Added --osp:numthreads <n> command line option to restrict the number of threads OSPRay creates
• Various bug fixes, cleanups and documentation updates throughout the codebase

Changes in v0.7.2:

• Build fixes for older versions of GCC and Clang
• Fixed time series support in ospVolumeViewer
• Corrected memory management for shared data buffers
• Updated to ISPC 1.8.1
• Resolved issue in XML parser