Line Divide POP
Summary
The Line Divide POP takes any set of line strips, and for each it generates a new line strip that is subdivided using various interpolation methods. The default is linear interpolation with 4 divisions between incoming points.
You can choose the Interpolation Method, the default being Linear interpolation, but you can also choose spline types like Cardinal, BSpline, Beziers and Quadratic. With the spline types, it can use incoming attributes (like those set in the Line POP) that specify the spline properties like Weight, tangents (TanIn and TanOut), tangent constraints (TanInConstraint) and/or tension. It will also interpret an interpolation method per-point if a SegMethod attribute exists.
There are two stages of doing divisions, The first stage allows setting the total divisions for the line strip, or divisions per-segment, dividing by distance along the curves, or by curvature of the line strip. It interpolates all the attributes.
The second stage lets you further re-sample the line strip with one of three methods: Divisions per Line Strip, Distance between Points, or Points as Keyframes.
Points as Keyframes interpolates by treating one attribute as an independent variable (like Time, or U), like a y = f(x) mathematical function. (For example, if you have an attribute Time on the points, you can resample curves at equal steps of time, assuming you curves express values over time.)
NOTE: The Maximum Number of Vertices parameter is required because it is not known on the GPU how many points you will end up with, and the GPU needs to pre-allocate enough memory to do the job. Oherwise line strips will be truncated.
To add: distinguish the different beziers, explain TanInConstraint. ControlPoint attribute (laser)
See also Line POP, Curve POP, Point POP, Primitive POP, Pattern POP.
Parameters - Divide Page
divmethod - ⊞ - The method to apply the divisions.
- None
none-
- Divisions per Line Strip
linestrip-
- Divisions per Segment
segment-
- Distance between Points
dist-
- Distance by Curvature
curvature-
divs - The number of divisions.
mindist - The minimum distance between points in the output line strips.
maxdist - Divide the line so there are no two adjacent points farther apart than this distance - max distance between points.
minmaxbias - Bias of point creation - more near the minimum or more near the maximum distance.
byedge - When dividing using the distance between points, whether to restart at each segment (edge).
addctrlpointattr - Whether to output a ControlPoint attribute set to 1 for control points.
maxverts - Sets the number of vertices to be allocated. It should be bigger than the actual number of vertices created (visible in info popup). More vertices allocated use more GPU memory.
Parameters - Interpolate Page
interpmethodpersegment - ⊞ - When toggle is on, it uses a separate interpolation method for each segment in the input line strips.
- Interpolation Method per Segment
interpmethodpersegment-
- Segment Method Attribute
segmethodattr- Attribute scope for the segment method index.
interpmethod - ⊞ - Method to use for interpolation.
- Linear
linear-
- Cardinal (Interpolating)
cardinal-
- BSpline
bspline-
- Cubic Bezier With Tangents
cubicbeziertang-
- Cubic Bezier
cubicbezier-
- Quadratic Bezier
quadraticbezier-
useweight - ⊞ - When on, the points will have a weight attribute affecting the tightness of the curve around the point.
- Weight Attribute
useweight-
- Weight Attribute Name
weightattr- Specifies the scope of the attribute that stores weight values
usetanin - ⊞ - When on, the points will have a attribute to be the tangent going into the point.
- In Tangent Attribute
usetanin-
- In Tangent Attribute Name
taninattr- Name of the incoming tangent attribute.
usetanout - ⊞ - When on, the points will have a attribute to be the tangent going out of the point.
- Out Tangent Attribute
usetanout-
- Out Tangent Attribute Name
tanoutattr- Name of the output tangent attribute.
usetaninconst - ⊞ - When on, the points will have an attribute to be constraints of a curve at that point..
- In Tangent Constraint Attribute
usetaninconst-
- In Tangent Constraint Attribute Name
taninconstattr- Name of the in tangent constraint attribute.
clamped - When using Cardinal or BSpline interpolation, whether to duplicate the start and end control points so the resulting curve start and end at the control points. Only has an effect on open line strips.
tension - Controls how tightly the cardinal line strip bends through the control points
Parameters - Resample Page
resamplemethod - ⊞ - Resampling method used after division.
- None
none-
- Divisions per Line Strip
linestrip-
- Distance between Points
dist-
- Points as Keyframes
keyframes-
resampledivs - The number of divisions.
indvarattr - Attribute to use as the independent variable.
indvarstep - Step size to use for the independent variable, usually a fraction of the independent variable range.
resamplemaxverts - Sets the number of vertices to be allocated. It should be bigger than the actual number of vertices created (visible in info popup). More vertices allocated use more GPU memory.
maxtries - Max number of iterations for binary search when linearly resampling.
rmvunusedpts - Removes unused points not referenced by primitives.
resamplemaxdist - Maximum Distance between Points
Parameters - Common Page
bypass - Pass through the first input to the output unchanged.
freeextragpumem - Free memory that has accumulated when output memory has grown and shrunk.
delinputattrs - Only output which attributes you specify in this POP - helps isolate attributes into a separate branch.
Operator Inputs
- Input 0: -
Info CHOP Channels
Extra Information for the Line Divide POP can be accessed via an Info CHOP.
Common POP Info Channels
Common Operator Info Channels
- total_cooks - Number of times the operator has cooked since the process started.
- cook_time - Duration of the last cook in milliseconds.
- cook_frame - Frame number when this operator was last cooked relative to the component timeline.
- cook_abs_frame - Frame number when this operator was last cooked relative to the absolute time.
- cook_start_time - Time in milliseconds at which the operator started cooking in the frame it was cooked.
- cook_end_time - Time in milliseconds at which the operator finished cooking in the frame it was cooked.
- cooked_this_frame - 1 if operator was cooked this frame.
- warnings - Number of warnings in this operator if any.
- errors - Number of errors in this operator if any.
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