WeaverBird 0.3 is the new alpha plug-in for topological transformations in Rhino 4.0 and Grasshopper 0.6.0059. A new build is now available for Grasshopper 0.7.0030. It helps smoothing, modifying and preparing meshes for rapid manufacturing technologies.

WeaverBird 0.3 Common. For Rhino 4.0 and both Grasshopper 0.7.30 and 0.6.59. Please upgrade to this version if you are using any earlier releases. To install, right click, choose “save as…” and then double click the file to launch the setup.
WeaverBird 0.2 ValueTypes. If you need the previous version (for Rhino 4.0 and Grasshopper 0.6 only).

Main topological commands:

Catmull-Clark smoothing (wbCatmullClark). Calculates the type of mesh-based recursive subdivision described by Edwin Catmull and Jim Clark, at first in 1978. The resulting mesh always consists of quadrilaterals.

Split mesh into Quads (wbSplitQuad). Calculates a new mesh, which is formed of only quads and generally appears similar to the old one, except that it is welded. It is topologically equivalent to the Catmull-Clark subdivision.

Loop smoothing (wbLoop). Calculates the type of mesh-based recursive subdivision described by Charles Loop, at first in his Mathematics thesis in 1987. The resulting mesh always consists of triangular faces.

Split mesh with inner face (wbSplitPolygons). Places a new face departing from the middle of each original face edge. Caps the remaining hole with Sierpinski triangles.

Sierpinsky Triangles subdivision (wbSierpinskyTriangle). Places a triangle in each corner of a mesh face. The mesh will have one more hole per face.

Frame (wbFrame). Computes a new mesh with higher naked edge count, where each face has a new hole in the center and resembles a picture frame. The resulting mesh always consists of quad faces.

Carpet (wbCarpet). Computes a new mesh with higher naked edge count, where each face has a new hole in the center. The resulting mesh always consists of quad faces, and can be used to compute a Sierpinski carpet.

Window (wbWindow). Replaces each original mesh face with a new one, reconstructed on the inside. Each face has the same number of sides as the original one.

New mesh primitives definitions:

wbPrism, wbAntiPrism, wbPyramid, wbDiPyramid

Additional commands:

- wbOptions. To see the main log, set up the threading model, control the maximum time a single operation is allowed to take, and set options for the Loop subdivision scheme (to use Loop’s receipt or Warren-Weimer’s one).

- wbProperties. Opens a window with topological information about any mesh object in Rhino. Exposes triangular and quad face counts, edge count, current and welded vertex counts.

This list of C# scripts is a work in progress and is open for requests. Supporting  v. 0.6.0043.

baking & Referencing
	bakeName GH 0.6.0012 GH 0.6.0018 GH 0.6.0043GH 0.6.0059	obj (geom) – a list of objects to bake name (string) – a list of names (common Rhino property) activate (bool) – one go-no-go signal, or a list thereof A (strings) – a list explaining the result(s)
	bakeAttributes GH 0.6.0012 GH 0.6.0018 GH 0.6.0043	obj (geom) – a list of objects to bake name (string) – a list of names layer (string) – Rhino layer name(s) color (onColor) – screen+print color(s) lineT (string) – the name of a linetype. Please only use with custom names. pWidth (double) – printing thickness(es) wires (int) – number(s) setting the quantity of wires, as in the property panel material (int) – GH shader(s), containing a Rhino material activate (bool) – one go-no-go signal, or a list thereof A (strings) – a list explaining the result(s)
	findID findRef GH 0.6.0012 2009 06 19	x (geom) – a Rhino geometry A (string) – The Rhino ID A (MRhinoObjRef) – The Rhino Ref
Automatic Sections
	contours GH 0.6.0012 GH 0.6.0043 2009 06 04	input (geom) – the objects to contour axis (onLine) – a line identifying the origin and end of the sectioning axis dist (double) – the interval between sections geomOut (geom) – a list containing all geometries meshOut (geom) – a list containing all geometries deriving from a mesh brepOut (geom) – a list containing all geometries deriving from nurbs-types pts (geom) – a list containing all geometries deriving from curves and lines
Continous redrawing
	theEngine component for GH 0.6.0012 Compatibility release for GH 0.6.0018 available, but users are encouraged to use the new timer within GH. GH 0.6.0043 2009 06 06	isOn (bool) – one go-no-go signal speed (int) – a period, expressed in milliseconds, that sets the refreshing rate resetAt (int) – the last shown number in the series, which will be restarting at 0stopAt (int) – the last shown number in the series starting at 0 reset (object) – any object (or bool) passed here will make this component restart from 0 C (int) – the current count
	Buckets GH 0.6.0012 GH 0.6.0018 GH 0.6.0043 2009 06 10	x (list) – a list of points. For the bucket, it can be a list of anything. reset (object) – any object here will make this an empty list limit (OnInterval) – two numbers which set the max and min values for each internal point coordinate recov (int: 0, 1 or 2) – a method to recover in case the internal value exceeds limits: wrap world (restart from other side of domain), limit (stop at the threshold, or restart from middle of the interval. A (list) – the list in memory
	renderAnimation GH 0.6.0012 GH 0.6.0018 GH 0.6.0043 GH 0.6.0059 200906 10 (four examples, see last one)	geometry (list) – a list of objects to be added to the scene before rendering viewport (string) – the name of the viewport to use. If empty or non-existing, the active one will be used filePath (string) – a name of an existing folder. If empty, the folder of the open document will be used. If document not saved, the current user’s document folder will be used fileExt (string) – jpg, png, bmp, or another extension that the rendering engine supports material (shader) – a GH shader. If material has a name and name is already existing on the scene, then the material on the scene will simply be inherited. No need of double materials current (int) – the sequential number of the frame rectMem (bool, defaults false) – deletes redo+undo after each rendering activate (bool, defaults false) A (string) – a text, explaining the outcome
fonts
	txtLines GH 0.6.0012 2009 06 04	face (string) – the name of the font bold (bool, default false) italics (bool, default false) size (double, default 5.0) content (string) – the text shown pt (on3dPoint) – the point ancoring the text A (OnLine list) – a list containing all curves
Networking
	updReceiver udpSender GH 0.6.0019 Processing 1.0.5 + UDP library 2009 08 31	port (integer) – a resonable port number out (string list) – network echo client (UdpClient) – a .net framework udp client A (bool) – message received B (string) – message

Last week I have been visiting my brother in Barcelona. Maybe I should blame the maritime environment if I started experimenting with knots and threads. So, what I am going to show you today is a method to digitally knit yarn in Grasshopper. A similar definition to make a chaining fabric is provided at the end of the tutorial as well.

The stockinette stitch pattern

Download this Grasshopper definition

We are going to model the common stockinette stitch pattern at first, because this stitch can be easily adjusted to other knitting, chaining or weaving fabric compositions.

1. The Grasshopper file starts from a straightforward definition of a knitting tile made out of curves, a surface and some parameters. This tile is illustrated in the picture above and is exactly the one marked in the dashed “component” box. The tile is surrounded by a rectangle in the grasshopper canvas, so that you can quickly adjust it to other definitions, in case you should need.
2. A containing box is created, departing from the input curves. We are particularly lucky this time, because the open part of the curves can be exactely used to define the boundary box.
3. This tile of curves is then repeated on the surface using the surface morphing component of Grasshopper, which is particularly useful because it maintains the geometrical continuity of what is being positioned.
4. All curves are joined and rebuit using a custom-written C# method.
5. The piping component finally produces the pipes.

Chaining pattern

Download the chain definition

By minimally modifying the previous definition, we can obtain a series of chains on a surface. It similarly works with one tile, which is then copied on the surface. We could expand this definition by making each newly formed link (a closed curve) periodic.