Table of Contents

Official release

Date – 11 July, 2023

Download – Build 5.20.00


With Chaos Phoenix 5.20 we added support for Maya 2024.

We added a new option in the Sources allowing to create velocities in a specified direction or even create varying velocities based on a texture map.

Simulations now are about 10-20% faster than in Phoenix 5.10 overall. We also added a new 'Use GPU to Aid Simulation' option that would run the fire/smoke PCG Fluidity method on the GPU instead of the CPU, so it could speed up simulations with up to 20%. Now the Simulator also has a new Simulation Speed rollout that shows how much each simulation phase takes and shows you tips on how to speed up your simulations even more.

We added a new Axis Lock option for locking the rotation of Active Bodies, allowed the Standalone Simulator to exclude geometries, and also there are many improvements to liquid simulations, including the ability to have the adaptive grid expand vertically in ocean simulations.

We did many fixes to V-Ray IPR rendering of Simulators and Particle Shaders, and as always, we fixed many other bugs so Phoenix would be the most stable fluid software you've ever used!



NEW PHOENIX Support for Maya 2024

NEW STANDALONE SIMULATOR Support for geometries and Sources in the Scene Interaction Include/Exclude list

NEW SUBMITTING SIMULATIONS Generate images from the cache sequence after Deadline simscene simulations

NEW SOURCES Source option to create velocities in a certain direction or based on a texture

NEW USER INTERFACE New 'Simulation Speed' rollout, showing the heaviest computation phases during simulation with tips on how to speed them up

NEW PRESETS Create geometry for Toolbar Presets if none is selected


IMPROVED FLIP LIQUID SOLVER Apply the Splash "Initial Velocity Multiplier" when splash particles split into smaller ones, not just when they are born from liquid particles

IMPROVED FLIP LIQUID SOLVER Changed the defaults of the Max Outside Age, Splash Amount, Splash To Mist, Splash Split, Mist Air Drag, Splash Initial Vel. Multiplier and Randomization to more realistic ones

IMPROVED FLIP LIQUID SOLVER Sped up liquid simulations by up to 15%

IMPROVED FLIP LIQUID SOLVER Speed up with WetMap simulation up to 2x

IMPROVED FIRE/SMOKE SOLVER New "Use GPU to Aid Simulation" option that runs the PCG Fluidity (Conservation) method on GPU, which could speed up the simulation overall

IMPROVED ACTIVE BODIES Option in the Axis Lock to lock the rotation of the Active Body to the original. This allows boats to lean while turning if this is a part of the original animation

IMPROVED ACTIVE BODIES Show the name of the selected Active Body solver in the Liquid rollout

IMPROVED STANDALONE SIMULATOR Turn off the 'Read Cache for Preview' option of Simulators during simscene export to make the timeline scrolling faster

IMPROVED OCEAN MESHER Support for rendering ocean with adaptive grid expanding vertically

IMPROVED V-RAY IPR Do not force Particle Shaders in Volumetric mode to Volumetric Geometry in V-Ray IPR CPU

IMPROVED SUBMITTER Now the Phoenix installer ships the Deadline plugin for simscene submission - it's located in Phoenix's installation under a deadline_plugin directory, and must be copied to the 'plugins' directory in your Deadline repository

IMPROVED CACHE I/O Sped up writing of VDB caches from the simulation or from the cache_converter with 30%

IMPROVED CACHE I/O Sped up simulations using the Grid Velocity channel in the Output rollout (even if the Cacheless Simulation option ON) with up to 5%

IMPROVED PREVIEW Sped up the particle preview - now simulations using it are up to 10% faster

IMPROVED PREVIEW Sped up the particle preview of AUR caches from moving simulations when Auto Scale Color is ON

IMPROVED ANIMATION New 'Auto Origin' control in the Input rollout for automatically setting the Cache Origin and Timeline Origin to the beginning of the loaded sequence

IMPROVED TEXUVW Isosurface render mode support for TexUVW

IMPROVED USER INTERFACE New Windows icons of the Cache Converter, Standalone Preview, Standalone Simulator and the Node Viewer, as well as the associated AUR, VDB, F3D, PRT and SIMSCENE file formats

IMPROVED USER INTERFACE Update the 'Elapsed', 'Estimated Left' and 'Performance' sim stats and the simulation progress on the Simulation rollout when scrolling through already simulated caches

IMPROVED USER INTERFACE Show an error at the start of the simulation if the PHX_FOR_MAYA20NN_MAIN environment variable is missing

IMPROVED USER INTERFACE Reordered the Preview rollout so most On/Off switches for the different types of previews are near the top and disabling the Mesh, GPU, Particle, Voxel, Streamline and Slice previews hides their respective controls

IMPROVED CACHE CONVERTER Extended the "Unrecognized Argument" error message when the input path was not with the correct format


REMOVED PHOENIX Dropped support for Maya 2019

REMOVED USER INTERFACE Hid the 'Auto Save Before Simulation' option from the Simulation rollout

REMOVED USER INTERFACE Hid the 'Diffuse Lighting' option from the GPU Preview section - it's always ON by default

REMOVED USER INTERFACE Removed the V-Ray IPR Support' option from the Phoenix Global Preferences - now it always defaults to ON


FIXED FLIP LIQUID SOLVER Movement of a Simulator with Fillup For Ocean caused the open boundaries to interact with the fluid

FIXED FLIP LIQUID SOLVER Animating the 'Splash To Mist' to zero deleted all existing Mist particles

FIXED FLIP LIQUID SOLVER Foam Volume higher than 0 caused Foam particles to pass through the Simulator's jammed walls

FIXED ACTIVE BODIES Active Bodies with center of mass different than the pivot moved differently than manually animated ones

FIXED ACTIVE BODIES Restoring an Active Body simulation did offset the animation curve at the restore point

FIXED STANDALONE SIMULATOR Animated options in Maya got exported to simscenes with 1 frame offset

FIXED SCENE BODY INTERACTION Bodies rotating very slowly were not updated by the simulator every frame, especially with high number of Steps Per Frame

FIXED SOURCES Fire/Smoke emitted from particles via a Source got clipped to the particle's bounding box with high 'Custom Part. Radius'

FIXED WAVE FORCE Crash during simulation when using a Wave Force with an Ocean Texture with Displacement Scaling

FIXED VOLUME SHADER Wrong Grid-based Volumetric Motion Blur with VDBs whose bounding box does not start at 0,0,0

FIXED VOLUME SHADER Crash when basing the Smoke Color on the Speed channel of VDBs whose bounding box does not start at 0,0,0

FIXED VOLUME SHADER Fire in Fully Visible mode did not render when Based On was set to the Grid RGB channel

FIXED VOLUMETRIC ILLUMINATION Self-illumination of the Fire did not work if Based On was set to the Grid RGB channel

FIXED PARTICLE SHADER Rendering slow-down with Particle Shader in Bubbles mode with Volume Light cache disabled on NUMA machines between V-Ray 5 and V-Ray 6

FIXED PARTICLE SHADER Black artifacts with Particle Shader in Points mode when there were many points on top of each other and the Point Radius or the Shadow Strength were high

FIXED V-RAY IPR Crash when enabling/disabling the Visibility of a Simulator in Volumetric mode while running V-Ray CPU IPR and moving the Timeline slider

FIXED V-RAY IPR Crash when a Simulator in Volumetric rendering mode was made visible after starting V-Ray IPR

FIXED V-RAY IPR Changing any settings or changing the timeline frame of Simulators or Particle Shaders in Volumetric Mode did not update in V-Ray IPR CPU and also IPR GPU

FIXED V-RAY IPR The Simulator's preview frame did not update when scrolling the timeline during V-Ray IPR

FIXED GPU PREVIEW When Scattering was set to Disabled, the 'External Scatter Mult' still affected the GPU Preview

FIXED STANDALONE PREVIEW 'Save Sequence' saved only one image if used after 'Save Current Frame'

FIXED PREVIEW Streamlines preview was not updated correctly until the current frame was changed

FIXED PREVIEW The streamlines viewport preview was transformed in an incorrect way in certain cases

FIXED PREVIEW Enabling the Force voxel preview disabled all the other voxel previews

FIXED PREVIEW Force Preview for Wave Force was only visible during simulation

FIXED CACHE I/O Simulating to VDB did not show correct simulation info in the Simulation rollout

FIXED CACHE I/O Can't open the particle ID channel of particle systems that have more than 268 million particles from AUR cache files

FIXED CACHE CONVERTER Converting from a VDB with vector3 color to AUR lost the background color and made it black

FIXED CACHE CONVERTER Crash if decompressing the ID channel of an AUR particle channel fails

FIXED PROPERTY LISTER Creating properties from the Property Lister caused primitives to disappear from the list

FIXED FOAM TEXTURE Foam Texture did not render when the connected Ocean Texture' Rate of Change was set to 0

FIXED PRESETS Тhe Jet Engine preset in Maya rendered incorrectly with V-Ray GPU because it used Smoke Opacity Based On Temperature instead of Simple Smoke