The toolbar that stretches across the top of the FumeFX attribute editor dialog specifically involves simulations and caches. These toolbar buttons include actions such as starting, stopping or pausing the simulation. From here, for example, you might choose to play your results straight through, or perhaps, just calculate a single step of the simulation.
Tasks in FumeFX are divided into several steps.
- Default Simulation (starting from an empty grid or using initial state)
- Wavelet Simulation
- Post Processing
FumeFX offers several simulation modes.
Default - This mode lets you to quickly simulate a low detail grid which can be further refined in Wavelet mode. If adding a Wavelet Turbulence generated detail, you can use it to create highly detailed simulation to which you can then incorporate further detail by using Fluid Mapping.
Initial State - This mode starts the simulation from a snapshot - a selected frame of the simulation, whose initial conditions were previously saved to a simulation file (.fdc) or output file (.fxd). The file can be selected by the right click over the Start Sim button.
If it hasn't been selected yet, a file selection dialog box will open, prompting you to select it.
If you are using an fxd file for the initial state make sure that such a file contains velocity channel.
Wavelet - To be able to use this mode, you need to have caches prepared by using Default simulation mode first. This mode will reload the Default caches, upscale simulation grid and use saved information to create additional detail.
Post - Post mode allows you to retime and optimize caches created in Default or Wavelet modes. Caches optimization allows excluding of channels that are no longer needed. This can be very useful for building .fxd caches with minimum data needed for rendering. Second option is to optimize grid dimensions which will result in a tightest possible container around smoke/fire. Using both methods, files sizes can significantly decrease and memory requirements will decrease, so you can expect faster rendering times.
Start - Select this button to run a simulation from the Start Frame to the End Frame (parameters that are available inside the Output Rollout). Throughout this simulation, an open Preview Window will show the most recently calculated frame. Note that during the simulation, FumeFX will not block user interface. While FumeFX is running a simulation, you can change simulation parameters or even source and object parameters. However, you will not be able to render, change simulation type, change Extra Detail mode or change input cache.
In Simulation Loop mode parameters such as Grid Dimension, Exporting Channels, Simulate Smoke/Fuel are updated when simulation starts over.
Pause - Simulation can be paused in any given moment.
Cancel - During the simulation click this button to initiate immediate simulation Cancel. No stop/continue data will be saved.
Continue - You can use this button to Continue a simulation from the point at which it had been stopped with the Stop button in the Status Window. FumeFX can continue from any frame that has already been calculated, provided that the velocity channel was exported.
Right click on the Continue button will provide you with few additional options.
Another option is to Continue from the current frame output; the position of the Maya time slider indicates this continuing point, right click on this button and select "Current Frame Output".
You can also Continue from any snapshots that you have specified in the Snapshot options under Preferences; right - click for a pop - up list of available snapshots to continue from. If snapshots were created with different grid parameters, you will be able to select Show same grid settings only, which will limit the selection range to matching files.
Stopping and continuing a simulation from a snapshot file will give you the exact same results as running a simulation uninterrupted. You can also continue from output files; however, since pressure is not saved in output files (.fxd), a slight difference will be introduced into the following frames. This difference will be evident in explosion effects.
In the events when simulation has reached the grid boundary and you needed it to expand even further, FumeFX allows you to change the grid dimensions and continue simulation from previous frame that has been calculated. This feature works only with adaptive grid.
You can use this option to start a Default simulation, Initial State simulation, Wavelet Turbulence simulation and Retimer simulation. It is not possible to continue a simulation.
Note: Before sending the scene for BB Simulation, please select the Maya Software renderer.
Run simulation through BackBurner/Batch Render - This is a toggle button. When on, user can assign BackBurner jobs or start Batch Rendering and FumeFX will run simulation before the rendering begins. See FumeFX SL for more information on how to set up for BackBurner simulation on remote computer.
Preferences - This button opens the Preferences dialog box, which lets you quickly configure local or global parameters.
Lets you to choose which cache will be loaded. If you select a cache that isn't present an error will show up.
Note: Depending on the selected cache, Stop and Continue buttons will be enabled or disabled. For example, when Wavelet cache is selected it is not possible to start Wavelet Simulation.
Draft Mode - When enabled, FumeFX will load caches at reduced resolution for viewport. This is very useful when you're working on shader adjustments or test renderings.
Read Only Mode - Caches are temporarily in read - only mode and they cannot be overwritten from the FumeFX UI. You can still delete them from the Windows Explorer.
Select Caches - Allows you to select caches to be loaded. Right click for more options.
Delete Caches - Clicking on this icon will delete all the related caches.
Relationship Manager - By using this window user can easily select which objects will be used in simulation and lights for rendering.
FumeFX Compute Sequence Editor - By using this editor user can change the sequence of sources and/or effectors application. The sequence will be most noticeable when using multiple effectors on the same channel (see Tutorial 10).
FumeFX Preferences allow you to customize the way in which your system handles each instance of simulation as well as the overall simulation data. The Preference window can be opened via the Preferences Icon in the Modify Panel Toolbar (with the FumeFX Grid selected), or from the Preferences Menu within the FumeFX UI floating dialog.
Per File Parameters
Clear RAM After Simulation - This option is on by default; if de - selected, FumeFX grid data will remain in RAM (computer memory) until you render the scene or run another simulation. The main reason to turn this option off would be in order to save the fluid state in the snapshot file after the simulation has ended. However, when option Ability To Stop/Continue is enabled, it will save a .fdc cache for the last frame computed.
These options affect the way you manage data from the individual states of a given simulation. These are local parameters, which are saved with each FumeFX instance.
The following options save the state of the simulation at specified frames, under the same name and path as output files, but with a different extension (.fdc). This makes it possible to continue the simulation from those frames (right click on the continue button to see available caches), or use them as starting point for other simulations with the same grid size.
None - If checked, FumeFX will not save any simulation states.
Every Nth frame - This option saves the state of the simulation every N frames, relative to frame 1 on the time slider.
Frames - With this option, you can save simulation states at specific frames. Enter your chosen frame numbers, separated by commas.
Delete Snapshots on Scene Exit - This option will delete all "Nth frame" and "Selected frame" files when closing the scene or deleting the FumeFX object.
Ability to Stop/Continue checkbox - With this option enabled, all necessary data needed for FumeFX to stop and continue a simulation will be saved to disk. This means that once you have stopped your simulation, you can change any parameters and then continue from the frame that you stopped at.
The preferences in this group define how FumeFX simulation files are handled. These parameters, like Maya preferences, are independent of scene and FumeFX instances.
Switch to Sim Only Mode - Select this option if you want to switch from full version of FumeFX to SL version. After this option is changed, FumeFX requires Maya to be closed and re - opened.
Paths & Logs Options
The parameters in this group affect the configuration of output files.
Default Output Path - Here, the output path and file name will be automatically generated whenever a new FumeFX object is created. Inside the default output path, a directory will be created based on the scene name. Output file names will be generated as "FumeFX_Object_Name_FrameNumber.fxd." If the scene is still untitled, a folder is created with a random file name, such as "FumeFX24345656.fxd."
Auto Synchronize Paths - FumeFX handles several paths for various cache types. If you have all the caches stored inside the same folder, then this option might be handy for you. If you change Default Path (Output rollout) it will make all other paths to properly reflect this change.
Save Simulation Logs - Select this option is you want FumeFX to save simulation log to a text file.
DC Cache Timeout - This value (in seconds) is used only when "Deferred Caches" is enabled. If the cache file does not become available during this period, the simulation will be terminated.
Esc Behavior Option
These options define what will happen with the simulation when user hits the "ESC" key.
Stop Simulation - Simulation will stop when frame is completed. A .fdc file will be generated as well.
Cancel Simulation - Simulation will cancel as soon as possible, leaving the current frame incomplete, so it will be impossible to continue from that particular frame.
Multithreading options define the resources you use during simulation. You can choose whether to Use all available CPUs, or manually set the number of simulation Threads up to the current maximum of 48.
FumeFX has the ability to save caches into the field3D format. Proprietary FumeFX compression is the same as found inside the .fxd file and compared to gzip it is faster and produces smaller cache files. The gzip compression is intended for companies that require access to FumeFX cache data for the purpose of additional manipulation.
Proprietary FumeFX - This compression has a very good compression vs time characteristics. However, other packages will not be able to read it unless they're using the FumeFX I/O library.
gzip - This is the compression that other packages will be able to read. Be prepared for longer simulations due to the low speed of gzip compression.
Notify Progress - Will send notification emails every Nth frames.
Notify Completion - An email will be sent when the simulation is finished. There is an option to attach the simulation log as well.
From/To/SMTP - Standard email settings. Please not that there is no option to use SMTP that requires password.