I want to dynamically (during “run-time”) cut off a piece of a dropping cloth,
without prefracturing it. As if it was cut with a pair of scissors, while falling
or being animated.

In this example, I attached “breakthreshold” (0.0) and “breaktype” (strechstress)
attributes to an animated grid and transferred that to the cloth in a SOP-solver.

This does indeed work with pre-fractured parts, but my manually transferred
attributes of the same types and values do not have any effect.

Is what I'm trying here even possible?

Thanks
AS

AkkiSan
In this example, I attached “breakthreshold” (0.0) and “breaktype” (strechstress)
attributes to an animated grid and transferred that to the cloth in a SOP-solver.

This does indeed work with pre-fractured parts, but my manually transferred
attributes of the same types and values do not have any effect.

not sure what you mean by pre-fractured vs manually transferred attributes

pre-fracturing is not about those attributes, but about separating the polygons so that they don't share points and then use Weld constraints to fuse them together for sim
only such fused points can break using those attributes

so the only way to get your cloth to break is to pre-fracture, you can however pre-fracture all the polys, so that the cloth can essentially break at any point, then it will obey your attributes as all points will be breakable

tamte
pre-fracturing is not about those attributes, but about separating the polygons so that they don't share points and then use Weld constraints to fuse them together for sim
only such fused points can break using those attributes

Thanks! Yes, that pretty much explains it.

tamte
so the only way to get your cloth to break is to pre-fracture, you can however pre-fracture all the polys, so that the cloth can essentially break at any point, then it will obey your attributes as all points will be breakable

I never tried this because I though that Houdini would explode, with a few thousands of
fractured parts, but at least considering only this isolated sim, that seems feasable,
in terms of computing power.


For a smooth and straight cut:
Assuming the cloth would always fall the same way, would it be possible to “snapshot”
the moment of the cut (e.g. fracturing the cloth with a plane) and reuse the new, now fractured
geometry in the same animation? Putting it back to the original state?