Wrap Capture SOP


This sop is the second of 3 sops that use one surface to deform another based on the weighted proximity of the points in the driver surface to the deformed one. This sop performs the capture phase on the surface you wish to deform.  The attributes it creates are understood by the Wrap deform sop and effectively "bind" the captured surface to the driver surface.


Input 1 is the geometry to capture and input 2 is the rest position of the driver surface.  If you are using the wrap prep sop in the deform stage the second input rest geometry should also be prepared with a wrap prep sop.

The first input can optionally have a "radius" point attribute attached to it that will override the radius parameter on the wrap deform sop.

The second input geometry can optionally have 3 additional attributes on it that modify the capture process.  The attributes are "partition",  "weight" and "radius".  The existance of "weight" and "radius" attributes will override the parameter values on the wrap deform sop.

The first input can also carry a "partition" point attribute.
The partition attribute is an integer point attribute taking the value 0,1 or 2 this works in conjunction with a partition primitive attribute added to the driver geometry.
A simple set of rules control how these partitons influence each other.   If a primitive in the driver surface has a partition value that matches that of the point partition attribute of the captured surface then the primitive can be concidered in the capture, additionally primitives with a value of 1 can influence both points with partition values of 0 and 2, however primitives of value 0 can't influence points of value 2 and vice versa primitives of value 2 can't effect points of value 0.


Radius of capture Distance from each point in the surface to capture to look for preped points from the driver surface.
This radius can be overriden by adding a radius float attribute to the capture surface or driver surface.
Limit # of inf. points Within the radius specified above many points may be found, this toggle allows you to specify a limit to the number of influence points returned.
Maximum # of inf. points The maximum number of influence points returned within the radius specified.
Fade effect Normally the weight of each point found within the radius is scaled by a distance falloff.  This menu allows for other additional methods to limit the effect of the influence points found in the radius.
Fade out value If fade out method is used to scale the weight then this value measured in radians is the angle at which the effect is scaled to 0. Usual values lie between -0.5 to -2
Kernel The distance falloff kernel used to weight the effect of the influence points.
Visualise weights Show the distribution of capture weights, this highlights areas that are more or less well captured.  Blue areas less captured and red areas more captured.
Capture surface colours If the driver surface has primitive colours on it then this will show the colours transferred onto the captured surface so you can see which primitives are influencing which areas. If have this work the prep sop must have 'keep prim cols' toggle turned on.