Ornatrix C4D: Auto Clump + Auto Grounding Needed

These 2 features (controllable with a simple checkbox) will be greatfull. Indeed, when we work with "Hair From Mesh Strips" and if we manipulate the driver mesh, regrounding is necessary each time. And the matter is we can't just disable grounding and re-ground, because if some texture are used to drive hairs (hairs density for example), this textures needs UV coordinate, so they need a ground mesh. And Ornatrix is really unhappy when we disable a grounding while operators need it. Actually it just crash, 100% of the time. The solution is to disable all the stack, disable grounding, Re-grounding, re-enbale the stack, all the time, all the day. With clumps, no crash to deplore, but each time we modify something before a clump, C4D users (maybe the same on othe platforms ?) have to reclump, waiting the result, eventually go to sub-clump operators, and Re-clump too, one by one to be sure the action is taking into account (sometime, if we go too fast, it doesn't work). So, all the day, we have to enable/disable, de-ground/re-ground, de-clump/re-clump, with the risk to forget, exporting hairs and render them for nothing. A lot of time wasted. That's why having the possibility to automate it will be a really time saver :-)
16 January 2023 #32286
Jeordanis Figuereo	Hello, I think the root of the issue is that something in your scene is changing the topology of your mesh strips, which will trigger a recomputation of the hair stack. In this case re-grounding and re-clumping IS necessary because the underlaying hair topology also changed. However re-grounding the roots is as easy as clicking Detach Roots and Attach again in Ground Strands. Check what is changing the topology of your mesh strips in the scene. Maybe some modifier is changing them at render-time as well(like a subdivision modifier). Regarding the crash, send me a scene where I can reproduce it. I think is much better to fix the bugs than implementing a new feature to avoid them. Jeordanis Figuereo (Product Designer. EPHERE Inc.) LinkedIn Discord
21 January 2023 #32302
FlowS	Now you say it, I use a Loft Nurb, built from splines. Loft Nurb isn't supposed to change the Topology or Uvs, BUT, to keep the control of the length of my hairs, I set up a rig where a "MoGraph Plane Effector" driven by a "Field", change the length of the splines used in the Loft Nurb and I think this is the effectivly the explaination. To do this, I had to use a MoSpline, to make the Splines compatible with the Plane Effector. That mean that I draw my spline, fill them in their equivalent in MoSpline, these MoSpline can change of Length thanks to the Plane Effector and a Field, and these MoSplines are used in the Loft Nurbs. And I saw when I made this rig that the topology wasn't exactly the same than if I was using the native spline directly in the Loft Nurb. I saw in the mean time that in wire view mode, some of the edge of the resulting mesh was changing. I think this is exactly what you describe. Concerning the "Detach Roots" and "Attach", it'is not as seamless as you think. In the attach video, I shaw what we need to do each time the topology change. As I said in the previous post, we have to disable all the stack after the "Ground Plane", otherwise, C4D Crash, especialy when maps are used in some operators like "Hairs From Guide". Indeed, "Hairs From Guide" need UVs, and UVs are recognised by this operator thanks to the "Ground plane" operator. If the "Hairs From Guide", doesn't have UVs anymore, It just crash. I attach 2 videos : -1 video of a simple scene where you can see the crash when degrounding while UVs are used in "Hairs From Guide" (I did'nt test if the crash happen with other operators wich need UVs) -1 video with the full process of Deground/Reground to avoid the crash. Concerning the autoclump, option, just behave that when the stack become complex before the clump, some operator (ike frizz) can change drasticaly the final result; That's why on Maya, you create "caching Options" : https://www.youtube.com/watch?v=JMtpAcQhODo And for the same reasons, on complex hierarchy, we have to ReClump all the time. clump by clump, because if we do this to fast, sometime, the clic isn't take into accout. So, we clic on the clump button, wait the view refresh, go to the subclump 1, clic, wait the view refresh ... all along the day. Attached Files: BUG-UNGROUNDING-01.mp4 (15473102 bytes), BUG-UNGROUNDING.c4d (463307 bytes), IMPROVE-AutoReGround_AutoReClump.mp4 (15404010 bytes),

Posted by:		FlowS
Data created:	14 January 2023