Arnold 4.5.1 Cinema 4D + MacOS / C4DtoA

System Requirements
Cinema 4D
R21.026 and above
S22.016 and above
R23.008 and above
S24.035 and above

Windows 10 or later, with the Visual Studio 2019 redistributable.
Linux with at least glibc 2.17 and libstdc++ 4.8.5 (gcc 4.8.5). This is equivalent to RHEL/CentOS 7.
macOS 10.13 to 10.15. Note that macOS 11 Big Sur is not certified.
CPUs need to support the SSE4.1 instruction set.
GPU rendering works on Windows and Linux only and requires an NVIDIA GPU of the Ampere, Turing, Volta, Pascal, or Maxwell architecture. We recommend using the 460.39 or higher drivers on Linux and 461.40 (Quadro), 461.40 (GeForce), or higher on Windows. See Getting Started with Arnold GPU for more information.
Optix™ denoiser requires an NVidia GPU with CUDA™ Compute Capability 5.0 and above.
Bug Fixes
c4dtoa#2388 IPR brightness issue in S24
c4dtoa#2389 Occasional crashes in IPR at startup

FEATURES

• New USD procedural: A new procedural is added to load USD files available via the Arnold Procedural object. Note that you can find the source code of this procedural and other USD components for Arnold at  https://github.com/Autodesk/arnold-usd. See  https://github.com/Autodesk/arnold-usd/releases for specific release notes. (#1545)
• New value shader: A value shader is added to the network editor which can output int, float, vector, color or string constant based on the selected data type. (#1542)
• New string replace operator: The new string_replace operator matches and replaces parts of string parameters, optionally depending on the OS Arnold is running on. (#1523)
• Cubic inverse camera radial distortion: A new cubic_inverse lens radial distortion compatible with the 3ds Max physical camera has been added. The classic cubic distortion is still the default. (#1523)
• Lens tilt controls: Lens Tilt Angle has been added to the perspective camera to control lens tilt angles with respect to the projection plane. The vertical and horizontal angles are specified in degrees. This is useful in architectural renderings to compensate for perspective transformation for vertical lines. (#1523)
• Lens shift controls: Lens Shift has been added to the perspective camera to shift the lens position. This is useful to recenter the subject after using tilt. The shift is given in normalized screen coordinates: +1 will move the frame center to the right or bottom edge. Note that lens shift will affect the render in a different way than Film Offset, notably with distortions or vignetting since one is a lens effect and the other just selects the part of the rendered image that will be output. (#1523)

ENHANCEMENTS

• Added animation controls to the image shader: Similar to the native Bitmap shader, the image shader now has an Animation tab to control timing. (#1536)
• Added particle radius variation: Random variation of particle radius can be controlled with new parameters under Radius Multiplier in the Arnold tag, Mesh particles tag or TP group. (#1538)
• Load textures from a folder in the shader network editor: New shortcut Alt+W~L is added to select multiple textures to be added as image shaders in the network editor. The command is also available under the Texture menu. (#1531)
• Add <resolution> token to text overlay: <resolution> can now be used as a token in text overlays (e.g. 1280 x 720). (#1515)
• Set proper minimum, maximum and step of vector type parameters: Vector type parameters (e.g. offset and scale in uv_transform) have the correct minimum, maximum and step (e.g. 0.01) set. (#1546)

FIXES

• #1565 Auto tx turns relative paths to absolute when exporting to ASS
• #1506 Hair growth along spline does not render
• #1558 Reading AOVs of Arnold Denoiser EXR input is broken
• #1252 Littering default.profraw files on Mac
• #1556 <samples> text overlay token is different on CPU and GPU

FEATURES

• GPU no longer in beta: Since the majority of the CPU features are now supported on the GPU, with lots of stability fixes and a good match between the CPU and GPU results, we're boldly removing the beta tag! For supported features and improvements please check the core Release Notes.
• New single-user licensing mode: Now users can sign-in with their Autodesk ID for being authorized, buying subscriptions, etc. The single-user licensing mode requires installation of the Autodesk Licensing Service and Single Sign-On components that can be installed from the Arnold License Manager tool if necessary.
• Arnold License Manager: The new Arnold License Manager tool allows to easily configure Arnold licensing through a graphical user interface. Users can select and change license type (e.g. Single-user, Network or RLM), sign in to their Autodesk Account, specify license server addresses for network licensing, etc. You can still configure licensing through environment variables, such as ARNOLD_LICENSE_ORDER, solidangle_LICENSE, ADSKFLEX_LICENSE_FILE, in which case they override the settings in the Arnold License Manager configuration file.
• Material export and Material import: Materials can be exported to ASS files and MaterialX files (.mtlx) via the C4DtoA > Utilities > Material > Export... menu item or via the Alt+W~X shortcut in the Material Manager. Materials can be imported via the C4DtoA > Utilities > Material > Import... menu item or Alt+W~I shortcut. Selected shaders of a material can also be exported from the network editor.

ENHANCEMENTS

• Align nodes in the network editor: New Edit > Align nodes menu item and Alt+W~L shortcut is added to the network editor to align graph nodes in the layout.
• Notification when no license found or license will expire: Now a message is displayed in the render settings when no Arnold license found or two weeks before the license expires.
• New Licensing menu: Licensing menu moved to C4DtoA > Licensing with menu items to open the new Arnold License Manager, help and purchase pages.
• New aov_write_vector shader: This enables the writing of vector values into a vector typed AOV, for example for recording positional values. These would previously have been clamped when using RGB typed AOVs.
• Add Details and Project tabs to Arnold Sky: Light filters, user options, and light linking settings are moved to these new tabs to be consistent with other lights.
• Flush Caches menu moved under Utilities
• physical_sky now goes below horizon: The physical sky shader will now extend the sky color at the horizon all the way down to the bottom pole. This should remove the black band under the horizon when not using an infinite ground plane.
• OCIO roles: Roles defined in the OCIO config are now listed on the color manager UI.

FIXES

• Auto tx does not use the generated textures
• Export Ass with Expand Procedurals doesn't work
• Crash creating preset from an Arnold Sky
• X-Particles groups are missing when rendering takes
• Procedural does not respect scale in some cases
• Instance of a scaled procedural renders incorrectly
• Procedural as multi-instance does not render from the command line
• IPR forgets camera after undo and redo
• Material preview fails when texture is in a custom folder on the search path
• Number in path sometimes detected wrongly as frame sequence
• Attributes are not inline with lights in Light Manager in R21 Windows
• R21 command line hangs when invalid license server is specified
• Reference shader creates an extra node in R21

FIXES

• C4D Noise shader Loop Period does not work

FEATURES

• Load, save and delete shader user presets
• Load, save and delete shader network user presets

ENHANCEMENTS

• Render C4D Noise shader on the GPU
• Show progress bar in the IPR window
• Add Use implicit UVs parameter to the ramp_float shader
• Add Wrap UVs parameter to the ramp shaders
• Add Clamp and Default color parameter to the uv_projection shader
• Export shaders together with operator graphs
• Show estimated remaining time of GPU cache population
• Export all available grids in Arnold Volume by default
• Display errors of material preview renders in the console

FIXES

• XP particle color in the IPR does not match the Picture Viewer
• AOV write shader output is wrong when using polygon selections

ENHANCEMENTS
- Add bake geometry utility
- Add support for Particle Geometry object
- Export index of clones as user data
- Display light radius in the viewport
- Display quad light roundness in the viewport
- Use color temperature over the light texture
- Use Selection object in light linking
FIXES
- Light radius should be a length unit type parameter
- Wrong displacement when driven by varying user data

FIXES

FEATURES
- GPU rendering (BETA): You can now switch between CPU and GPU render devices interactively and expect visually similar results. NVIDIA® GPUs from Turing™ to Maxwell™ architectures are supported, and Arnold will take advantage of multiple GPUs, NVLink™ and NVIDIA® RTX™ hardware accelerated raytracing if available. Note that due to beta status of this feature, a number of features are missing, performance is not final, and use in production is not advised. Unsupported lights, shaders, parameters and AOVs are marked with an asterisk (*) in the label. We plan to gradually improve this in subsequent releases and will appreciate your feedback. For a complete description of requirements, features and caveats, see Getting Started with Arnold GPU.
- GPU rendering from the command line: The render device (CPU or GPU) can be controlled from the command line via the -arnoldDevice [cpu|gpu] flag.
- Pre-populate GPU cache: The OptiX™ disk cache, which is automatically generated during JIT compilation prior to GPU rendering, contains a store of previously compiled OptiX™ programs, so that subsequent renders start faster. The pre-population is a heavy process and it is recommended that the pre-population is triggered after installing a new Arnold version, updating to a new NVIDIA® driver, or changing the hardware configuration of GPUs on the system.
- Visible lights: Quad, disk, cylinder and point lights now have a Camera and a Transmission attribute, allowing these lights to become visible to camera and transmission rays. These attributes are left to 0 by default, thus not changing the default behaviour of the non-visible lights.
- Improved random-walk SSS: A new randomwalk_v2 SSS mode has been added that scatters more accurately and deeply through highly-transparent/optically-thin objects, which produces SSS with more saturated colors around fine surface detail and heavily backlit regions of an object. Note that renders will be more costly and noisier than with the original method, since random walks will be on average longer and more random.
- MaterialX export: Bakes the shader and other look properties for one or more shapes (e.g. Arnold Procedural) to a .mtlx file along with the description of the shaders and shading graphs.
- Added uv_projection shader
- Added matrix_interpolate shader
- Anisotropy controls for coat in standard_surface shader
- Added include_graph operator
- Added denoise_albedo built-in AOV
ENHANCEMENTS
- Improved skydome sampling
- Improved adaptive sampling
- Smart opaque: built-in shaders now set the Opaque flag automatically based on whether or not the shader settings would require disabling the opaque flag on the object to render correctly.
- Improved bump and normal mapping
- Instantaneous shutter option: This new option in the motion blur render settings now keeps motion keys and only sets the camera ray times to be equal to the reference time. Use this with motion vectors instead of setting shutter intervals to zero.
- Support for negative transmission extra roughness in standard_surface shader
- Added time mode in ramp shaders: The ramp and ramp_rgb shaders now have an additional time mode that computes the input based on the current time and the camera's start and end shutter interval.
- Use implicit UVs added to the ramp_rgb shader
- Append frame number to the driver path automatically
- Added volume scattering to the shape visibility flags
- Expose autobump visibility
- Expose ignore list in the render settings
- Assign operator network to procedurals
FIXES
- Polygon selection does not work when the name has unicode characters in it
- Problem with special character in the uv_transform UV set name
- Wrong bump mapping with custom projection
- Bump mapping is too soft when UVs are tiled in the texture tag. Note that the look has changed following this fix and now it is (correctly) stronger when a custom UV projection or tiles are set in the texture tag.
API
- There are modifications in the C4DtoA API which require third-parties to recompile their C4DtoA extensions.

FIXES