Votes
3
Product:
iClone 7
Version:
7.92
Status:
Active
Issue 8054
Adjustable Physics Calculation Time for Sophisticated Scenes
It's an issue when you've built something from many props with many constraints and the only way to show it functionally held together is to lengthen the speed of the clip to give it more time to calculate but then you'd have to shrink it back to the original size later.

I've also found that Render Resolutions directly correspond to physics calculations. 4k output prevented my chain links from holding together but the iPhone Portrait resolution allowed the chains to remain intact.
OS: Windows 10
  •  13
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Submitted byAscensi
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COMMENTS (13)
Ascensi
Update: Getting close to 30 FPS on a physics chain link, I definitely see huge potential in a Physics Bake Manager where all the clips are copied over and all settings reduced to get a quick bake.
https://youtu.be/ZwrM2EdPZxU

To copy and paste your original tracks to a new area manually, stretch them out by double or more by setting speed to 50%, change your resolution settings, change the render to the lowest and shrink the viewport, make sure clips don't have existing physics, colliders are in their right place, transforms and scale is correct etc these are all things that need to be considered before baking and one tiny thing out of place or forgotten can drive a person mad and wreck their experience in iClone - at least when working with physics.  - Then once you have a good fast bake, you have to unshrink the physics clips to the size of the parent clip (in my case the parent is a character, the chain links were following a character's arm)  and move each chain link into position under the original clips (my clip again is a character)
Ascensi
I've attached a screen capture of physics frames being calculated faster with the lowest screen resolution using minimal mode for increased performance.  The incorrect areas of movement in the video is an example of recorded physics that were never completely removed. When you remove animations from objects from "Animation ---> Remove Object Animation" sometimes you have to do it multiple times to completely remove them otherwise it will *add onto* existing bakes rather than be replaced with the new physics calculation. An option to include "Explicit removal or rewrite of baked physics" is also essential to ensure a completely clean physics bake.
Ascensi
The Physics Manager should also have an option/script for processing constraint chain props to be unparented, freeze transforms then reparent as well at toggle all constrains in a group to physics on -this will help eliminate typical errors that prevent physics of constraint chains from misbehaving. My initial experience of the current physics had left me frustrated and sour until I started finding work arounds and suggestions Rampa had shared. I've also spent a lot of time talking with Rampa for his help on this but many of these issues could be solved and his time could be freed to help others to trouble shoot other problems. 

I've found that baking in minimal mode with 800 x 600 resolution bakes so fast, it skips the count of many frames on a 44 segment chain link . A "Bake Now" option to force minimal mode and the resolution to go even lower than that or temporarily disable it altogether would be incredible. I own Houdini Fx 18.5 license, bake times can take a long time - days or even a week on complex projects and if iClone had a Physics Bake Manager  setup for the long haul and you eventually started allowing simulations, you'd be ahead of everyone by far.

If Bake now also copied and stretched the clips, this would be ideal to help with accuracy and would help for bigger scenes and overall the simulations could rival the speed and accuracy of competitors.
Ascensi
To be  clear what I'm suggesting is a  Physics Bake Manager to Que Props and on the modify tab --> physics, the user can tag prop to be added to the que and additionally assign the prop belonging to a  group of physics props to sequence bake  them.

What this would entail is 

1. User enables auto physics/Physics Que Manager and optionally gives it a group name tag that other prop can be assigned to.

2. Press Silent Bake - Internally copying a prop or group of props/constraints in  the que  to a temporary hidden timeline to auto stretch the clip(s)  using the Physics Bake Manager settings and allow the user to set a percentage  to calculate how slow or fast the clip speed should be to get an accurate bake.  - providing the user the option to change screen resolution during the bake might also help accuracy and bake time - larger resolutions slow video cards down (FPS) so this actually make sense but it means the user will temporarily see their viewport resolution reduced.
 
3. Once completed the physics is copied back to the regular timeline with the original clip speed and the physics is disabled if auto physics/Physics Que Manager still has it check boxed.

This feature could also work silently or in idle mode allowing the user to keep working on their project save time by not needing to go through every prop with physics to enable, disable or play the scene by frame to get the physics calculated, it could all be done internally & more efficiently. 

If Reallusion is aiming to attract bigger clients/turn heads and allow users to show off sophisticated scenes, this will be an essential requirement. I understand Reallusion maybe testing/working on Soft Body Character Physics and currently in my own tests working with character physics, enabling soft vs soft collision in the Global Physics Settings causes iClone to crash on an i7 and a RTX 2080 Ti with 32 GB & 32 GB of Virtual memory when having two soft body characters interacting.  Although they might be integrating screen space particle colliders like PopcornFX has or tapping the physics engine of PopcornFX, this could increase performance exponentially and even pave the way for water simulation like Nvidia Flex https://developer.nvidia.com/particles but certainly, even this could possibly be added to the Physics Que Manager -the more ability for speed and efficiency the faster and amazing iClone projects could look and function. 

I hope this provides some insight and perspective. As I use iClone as an artist and developer, I try to give Reallusion a potentially easy solution to any limitation I find that severely impacts my creativity in a negative way and that might empower other users.
Ascensi
Hi Joanne, thanks, yes I do know how to bake first by frame mode then turn off the physics for final rendering. I was testing out many variables. Rampa had also informed me that stretching out the clip time will also help calculate the physics properly (that worked)  also changing the world scale lower also helped.. but I discovered that Viewport size also matters - the smaller, the more accurate.

 I've been talking with him in depth about these solutions and the solutions he's shared but I realize that they require a lot of tinkering, that it causes/would cause a lot of issues not apparent for the general user such as needing to slow the clip to get a better bake or change the viewport resolution, world scale  etc

My project contained cloth physics as well as constraints and I know technically one should be baked first by frame then physics disabled and enable physics on the other etc but some scenes are sophisticated (many physics parts) Perhaps in the future, in the time line and prop on the physics tab can have an auto disable physics using by frame mode check box (can be toggled on globally in the timeline for those marked  with auto disable or individually toggled on)

***So the physics system right now is ok for simple projects but not robust for management and calculation of sophisticated projects - the management part could sequence bake props added to a physics group que and temporarily adjust the time line (copied to a separate timeline internally for reducing clip speed &  baking per frame then copies it back  to the regular timeline with the original clip speed.)***
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