Download and Installation

Arnold, KtoA, and other downloads are available here.  Installation instructions come with KtoA, but can also be viewed here: Installation.


  • Arnold: 5.0.1+
  • Katana: 2.5v4+, 2.6v1+
  • Platforms:
    • Linux: x86-64, RHEL 6+ or compatible glibc
    • Windows: 7+ on x86-64, with VC++ 2015 redistributable installed


  • Updated to Arnold 5.0.1: Updated the Arnold core version to 5.0.1, which has new features such as polymesh volume containers, new APIs, speedups and several important bug fixes including fixing a memory leak with the ramp shaders, among others. See the release notes for more information. (#191)

    • Volume container mode for non-volume locations: Locations of type sphere, pointcloud, polymesh and subdmesh all now support setting step_size and volume_padding to turn them into volume containers, interpreting their shaders as volume shaders. The padding parameter is used to give space to the shader to do positional displacement with e.g. noise to add apparent resolution. (#191)

    • Radial distortion for perspective cameras: A new parameter in the global camera settings, radial_distortion has been added to aid in simple pincushion and barrel distortion effects. The typical range is from about -0.3 to 2.0, negative values producing pincushion and positive values producing barrel distortion. (#181)

    • Global AOV shaders: Previously, if a shader needed to run before all shader networks, such as is done with Cryptomatte, the shaders would need to incorporate the functionality or else a shader would need to be inserted at the root of every shader network. AOV shaders allow a shader to run after regular shading for every pixel sample without needing any modification to objects' shader networks. A new shader type, "aov" is provided that should list just shaders capable of this slot. (#193)

  • Support for Katana 2.6 series: KtoA supports and runs with Katana 2.6v1+. (#186)

  • Detailed logs for first live render frame: Live rendering will now print much more information for the first time rendering, and then pull back to be very quiet afterwards as it is now. This should allow examining logs for information without slowing down rendering performance or spamming the render log tab with too much information. (#187)

  • Gafferthree light filter and light filter references: Adding a light filter or a light filter reference in GafferThree below a light will properly add it as a light filter to the parent light. Light filters can be created outside of lights and then added to multiple lights using light filter references. Note that it is a known issue that light filters added in this manner don't update properly when changed in live rendering, but that is planned for a future release. (#15)

  • Improved procedural parameter control: Katana has traditionally stuck some extra parameters on all procedurals, such as frame, shutter, cropwindow, and katanaFullName. These parameters are usually ignored by most procedurals at best, and can conflict with expected parameters at worst. By setting the int rendererProcedural.args.__skipBuiltins attribute to something non-zero these built-in parameters will not be emitted. Also, a new hint rename was added that can be used to rename parameters; this is useful if you want to use a parameter name that Katana uses as a built-in, such as Yeti does with the frame parameter. (#182)

  • Restricted shader lists: When creating shaders of a specific type, such as displacement or light filters, the list of available shaders should be restricted better to compatible shader types. Some shaders not intended for that type may still show up in the lists, but the heuristic should be improved. Previously, KtoA only had a "light or not light" check for these shader types. (#194)

Bug Fixes

  • #189 Fix errors and warnings in pointcloud location translation

  • #192 Render crash using geometry.point.constantwidth in pointcloud translation

  • #195 Autobump broken


  • No labels