Plastic Deformation
The parameters of this section revolve around plastic, i.e., permanent, deformations. Imagine a narrow metal strip that you can bend: The strip will give up to a certain degree back to its original state when released but if this degree is exceeded, the strip will start to bend. This is the typical behavior of metals, for example. This does not quite fit within the bounds of a cloth simulation but the more functionality you have the better.
Below you can see various plastic deformations. From left to right: bending deformation, stretching deformation and soft-body strut deformation.
In Cinema 4D, plastic deformation is split in two (Soft Bodies even have a third set of parameters). As you know, the internal structure of a piece of cloth is defined using the settings Bendiness and Stretchiness settings to adjust the distance and bend constraints. And these are also responsible for creating the plastic deformation. These can be defined separately. This is why you will find two identical sets of parameters that are described together here.
Here you can define which deformation should behave plastically. Of course both can be activated at the same time. If you take a look at the image above: The continuous plane on the right is a result primarily of the plastic stretch and the indentation at the center is primarily a result of the plastic bend deformation.
If 2 bordering polygons are bent using this value or polygon edges are deformed along their length, a plastic, i.e., permanent deformation will result.
The two values can each also be defined by vertex maps at the point level. Point values of 0% will produce no plastic deformation and 100% in accordance with the Deform Past setting. Intermediate values will be converted proportionally.
Here you can define the degree of deformation: from 0% (none) to 100% (maximum deformation).
The Strength value can be scaled at point level using a Vertex map.
Some metals harden where they are deformed, i.e., their flexibility and elasticity is reduced in these regions. For this you must define positive values.
Other materials on the other hand will soften in the regions in which they are deformed. You must then apply negative values.
With regards to the internal constraints model it means that the constraints will be made harder or softer, respectively.
A value of 0 will disable the hardening effect.
Hardening can be scaled to point level with a Vertex map.
Soft Body Pole deformation
In addition to the parameters described above, Soft Bodies have strut constraints that can also deform plastically.
Use this to switch Plastic Deformation for Poles on and off.
Struts can deform plastically when stretched and/or compressed in their longitudinal direction. This can be defined here. If Both is selected, the Poles will be deformed when stretched or squashed if the Deform Past threshold value is exceeded.
When the simulation starts, the Poles will have individual lengths. If the length exceeds the value defined here in the course of the simulation (depending what is defined for Deformation Direction), the Poles will deform permanently.
If Tear Past was defined on point level you can place a Vertex map in Map. A Vertex value of 100% reflects the value defined for Tear Past. Since Poles are always connected to 2 points, the average value will affect both point weightings.
Specify here how strong the plastic deformation should be. If you define 100% here, the maximum deformation will take effect; if set to 0% almost no plastic deformation will take place; intermediate values will have a corresponding effect.
This parameter only affects the simulation if Poles actually enter the plastic region (i.e., exceed Tear Past). As long as Poles are within the elastic range, no differences will result.
If Strength is defined at point level, a Vertex map can be placed in Map. A Vertex value of 100% reflects the value defined for Strength. Since Poles are always connect to 2 points, the average value will affect both point weightings.
Some metals will, for example, harden at the location of the plastic deformation, i.e., the bendiness and stretchiness will be reduced. For this you must define positive values.
There are other materials that become softer in the range of a plastic deformation, you would then have to enter negative values here.
Transferred to Soft Bodies, this means the hardening or softening of the plastically deformed struts.
A value of 0 will disable the hardening effect.
If you want to define Hardening on point level, you can place a Vertex map in Map. A Vertex value of 100% reflects the value defined for Hardening. Since Poles are always connected to 2 points, the average value will affect both point weightings.