You can reuse and display an existing simulation to restart the simulation computation from the first non-computed frame.
Any time a scene is reloaded, each of these simulation operators verifies if its old PTP file sequence still exists. To do that, the file sequence “magic number” is compared with the magic number saved with the operator. If the PTP sequence still exists, an automatic restart on the last valid frame is performed.
From that frame on, further recomputation (due to any change in parameter, obstacle, emitter, particle type, etc.) starts from the Restart Frame+1, while all frames between the Start Frame and Restart Frame are preserved.
To restart a simulation
1. From the Output page of the FluidOp property editor, specify the Output Sequence file name in which to save the simulation in .ptp files (one file per frame). These files record all the simulation data for each frame of the simulation (see Caching the Simulation in PTP Files for more information).
2. Play the simulation to record the frames to file.
3. On the timeline, go to the frame at which you want to restart the simulation and select Restart from file on the Output page.
4. Click the browser button (...) beside the Output Sequence file name and select the .ptp file with the frame number that corresponds to the current frame you’re at.
All the frames of simulation before this frame are read from the file which means that they don’t have to be recalculated. Computation then starts from the current frame onward. When you restart, the simulation properties’ values can be different from those used to generate the .ptp file.
5. Each time you exit Softimage, delete a simulation operator, or close the scene, you can automatically erase all .ptp files that were recorded and cached. To do this, select Clean cached files. If you don’t select this option, the .ptp files are saved in the folder with the Restart file name you specified.
Autodesk Softimage v.7.5