extrusions

Modules

Module	Description
modeling/extrusions	所有二维图形（基本图形或运算结果）都可以通过多种方式进行拉伸（挤出）。在所有情况下，函数均返回运算结果，不会修改原始图形。
modeling/extrusions/slice	表示一个由边列表构成的三维几何体。

Typedefs

Name	Description
slice	表示一个由边列表组成的三维几何体。

modeling/extrusions

所有二维图形（基本图形或运算结果）均可通过多种方式进行拉伸（挤出）。在任何情况下，该函数均返回运算结果，且不会修改原始图形。

Example

const { extrudeHelical, extrudeLinear, extrudeRectangular, extrudeRotate, project, slice } = require('@jscad/modeling').extrusions

• modeling/extrusions
  • .extrudeFromSlices(options, base)
  • .extrudeHelical(options, geometry)
  • .extrudeLinear(options, ...objects)
  • .extrudeRectangular(options, ...objects)
  • .extrudeRotate(options, geometry)
  • .project(options, ...objects)

modeling/extrusions.extrudeFromSlices(options, base)

根据回调函数返回的切片，拉伸生成一个实体。

Kind: static method of modeling/extrusions
Returns: geom3 - the extruded shape
See: slice

Param	Type	Default	Description
options	Object		options for extrude
[options.numberOfSlices]	Integer	2	the number of slices to be generated by the callback
[options.capStart]	Boolean	true	the solid should have a cap at the start
[options.capEnd]	Boolean	true	the solid should have a cap at the end
[options.close]	Boolean	false	the solid should have a closing section between start and end
[options.repair]	Boolean	true	repair gaps in the geometry
[options.callback]	function		the callback function that generates each slice
base	Object		the base object which is used to create slices (see the example for callback information)

Example

// Parameters:
//   progress : the percent complete [0..1]
//   index : the index of the current slice [0..numberOfSlices - 1]
//   base : the base object as given
// Return Value:
//   slice or null (to skip)
const callback = (progress, index, base) => {
  ...
  return slice
}

modeling/extrusions.extrudeHelical(options, geometry)

Perform a helical extrude of the geometry, using the given options.

Kind: static method of modeling/extrusions
Returns: geom3 - the extruded geometry

Param	Type	Default	Description
options	Object		options for extrusion
[options.angle]	Number	TAU	angle of the extrusion (RADIANS); positive for right-hand rotation, negative for left-hand
[options.startAngle]	Number	0	start angle of the extrusion (RADIANS)
[options.pitch]	Number	10	elevation gain for each full rotation
[options.height]	Number		total height of the helix path. Ignored if pitch is set.
[options.endOffset]	Number	0	offset the final radius of the extrusion, allowing for tapered helix, and or spiral
[options.segmentsPerRotation]	Number	32	number of segments per full rotation of the extrusion
geometry	geom2		the geometry to extrude

Example

const myshape = circle({size: 3, center: [10, 0]}) // position for extrusion about Z
const mycoil = extrudeHelical({angle: TAU * 2, pitch: 10, segmentsPerRotation: 64}, myshape))

modeling/extrusions.extrudeLinear(options, ...objects)

Extrude the given geometry in an upward linear direction using the given options. Accepts path2 or geom2 objects as input. Paths must be closed.

Kind: static method of modeling/extrusions
Returns: Object ⎮ Array - the extruded geometry, or a list of extruded geometry

Param	Type	Default	Description
options	Object		options for extrude
[options.height]	Number	1	the height of the extrusion
[options.twistAngle]	Number	0	the final rotation (RADIANS) about the origin of the shape (if any)
[options.twistSteps]	Integer	1	the resolution of the twist about the axis (if any)
...objects	Object		the geometries to extrude

Example

let myshape = extrudeLinear({height: 10}, rectangle({size: [20, 25]}))

modeling/extrusions.extrudeRectangular(options, ...objects)

Extrude the given geometry by following the outline(s) with a rectangle.

Kind: static method of modeling/extrusions
Returns: Object ⎮ Array - the extruded object, or a list of extruded objects
See: expand for addition options

Param	Type	Default	Description
options	Object		options for extrusion, if any
[options.size]	Number	1	size of the rectangle
[options.height]	Number	1	height of the extrusion
...objects	Object		the geometries to extrude

Example

let mywalls = extrudeRectangular({size: 1, height: 3}, square({size: 20}))
let mywalls = extrudeRectangular({size: 1, height: 300, twistAngle: TAU / 2}, square({size: 20}))

modeling/extrusions.extrudeRotate(options, geometry)

Rotate extrude the given geometry using the given options.

Kind: static method of modeling/extrusions
Returns: geom3 - the extruded geometry

Param	Type	Default	Description
options	Object		options for extrusion
[options.angle]	Number	TAU	angle of the extrusion (RADIANS)
[options.startAngle]	Number	0	start angle of the extrusion (RADIANS)
[options.overflow]	String	'cap'	what to do with points outside of bounds (+ / - x) : defaults to capping those points to 0 (only supported behaviour for now)
[options.segments]	Number	12	number of segments of the extrusion
geometry	geom2		the geometry to extrude

Example

const myshape = extrudeRotate({segments: 8, angle: TAU / 2}, circle({size: 3, center: [4, 0]}))

modeling/extrusions.project(options, ...objects)

Project the given 3D geometry on to the given plane.

Kind: static method of modeling/extrusions
Returns: geom2 ⎮ Array - the projected 2D geometry, or a list of 2D projected geometry

Param	Type	Default	Description
options	Object		options for project
[options.axis]	Array	[0,0,1]	the axis of the plane (default is Z axis)
[options.origin]	Array	[0,0,0]	the origin of the plane
...objects	Object		the list of 3D geometry to project

Example

let myshape = project({}, sphere({radius: 20, segments: 5}))

modeling/extrusions/slice

Represents a 3D geometry consisting of a list of edges.

See: slice for data structure information.

• modeling/extrusions/slice
  • .calculatePlane(slice)
  • .clone([out], slice)
  • .create()
  • .equals(a, b)
  • .fromPoints(points)
  • .fromSides(sides)
  • .isA(object)
  • .reverse([out], slice)
  • .toEdges(slice)
  • .toPolygons(slice)
  • .toString(slice)
  • .transform(matrix, slice)

modeling/extrusions/slice.calculatePlane(slice)

Calculate the plane of the given slice. NOTE: The slice (and all points) are assumed to be planar from the beginning.

Kind: static method of modeling/extrusions/slice
Returns: plane - the plane of the slice

Param	Type	Description
slice	slice	the slice

Example

let myplane = calculatePlane(slice)

modeling/extrusions/slice.clone([out], slice)

Create a deep clone of the given slice.

Kind: static method of modeling/extrusions/slice
Returns: slice - a new slice

Param	Type	Description
[out]	slice	receiving slice
slice	slice	slice to clone

modeling/extrusions/slice.create()

Creates a new empty slice.

Kind: static method of modeling/extrusions/slice
Returns: slice - a new slice

modeling/extrusions/slice.equals(a, b)

Determine if the given slices have the same edges.

Kind: static method of modeling/extrusions/slice
Returns: Boolean - true if the slices are equal

Param	Type	Description
a	slice	the first slice to compare
b	slice	the second slice to compare

modeling/extrusions/slice.fromPoints(points)

Create a slice from the given points.

Kind: static method of modeling/extrusions/slice
Returns: slice - a new slice

Param	Type	Description
points	Array	list of points, where each point is either 2D or 3D

Example

const points = [
  [0,  0],
  [0, 10],
  [0, 10]
]
const slice = fromPoints(points)

modeling/extrusions/slice.fromSides(sides)

Create a slice from the given sides (see geom2).

Kind: static method of modeling/extrusions/slice
Returns: slice - a new slice

Param	Type	Description
sides	Array	list of sides from geom2

Example

const myshape = circle({radius: 10})
const slice = fromSides(geom2.toSides(myshape))

modeling/extrusions/slice.isA(object)

Determine if the given object is a slice.

Kind: static method of modeling/extrusions/slice
Returns: Boolean - true if the object matches a slice

Param	Type	Description
object	slice	the object to interrogate

modeling/extrusions/slice.reverse([out], slice)

Reverse the edges of the given slice.

Kind: static method of modeling/extrusions/slice
Returns: slice - reverse of the slice

Param	Type	Description
[out]	slice	receiving slice
slice	slice	slice to reverse

modeling/extrusions/slice.toEdges(slice)

Produces an array of edges from the given slice. The returned array should not be modified as the data is shared with the slice.

Kind: static method of modeling/extrusions/slice
Returns: Array - an array of edges, each edge contains an array of two points (3D)

Param	Type	Description
slice	slice	the slice

Example

let sharededges = toEdges(slice)

modeling/extrusions/slice.toPolygons(slice)

Return a list of polygons which are enclosed by the slice.

Kind: static method of modeling/extrusions/slice
Returns: Array - a list of polygons (3D)

Param	Type	Description
slice	slice	the slice

modeling/extrusions/slice.toString(slice)

Kind: static method of modeling/extrusions/slice
Returns: String - the string representation

Param	Type	Description
slice	slice	the slice

modeling/extrusions/slice.transform(matrix, slice)

Transform the given slice using the given matrix.

Kind: static method of modeling/extrusions/slice
Returns: slice - the transformed slice

Param	Type	Description
matrix	mat4	transform matrix
slice	slice	slice to transform

Example

let matrix = mat4.fromTranslation([1, 2, 3])
let newslice = transform(matrix, oldslice)

slice

Represents a 3D geometry consisting of a list of edges.

Kind: global typedef
Properties

Name	Type	Description
edges	Array	list of edges, each edge containing two points (3D)