---
title: "startSketchOn"
excerpt: "Start a new 2-dimensional sketch on a specific plane or face."
layout: manual
---

Start a new 2-dimensional sketch on a specific plane or face.



```js
startSketchOn(data: SketchData, tag?: FaceTag) -> SketchSurface
```

### Examples

```js
const exampleSketch = startSketchOn("XY")
  |> startProfileAt([0, 0], %)
  |> line([10, 0], %)
  |> line([0, 10], %)
  |> line([-10, 0], %)
  |> close(%)

const example = extrude(5, exampleSketch)

const exampleSketch002 = startSketchOn(example, 'end')
  |> startProfileAt([1, 1], %)
  |> line([8, 0], %)
  |> line([0, 8], %)
  |> line([-8, 0], %)
  |> close(%)

const example002 = extrude(5, exampleSketch002)

const exampleSketch003 = startSketchOn(example002, 'end')
  |> startProfileAt([2, 2], %)
  |> line([6, 0], %)
  |> line([0, 6], %)
  |> line([-6, 0], %)
  |> close(%)

const example003 = extrude(5, exampleSketch003)
```

![Rendered example of startSketchOn 0](data:image/png;base64,[encoded data, 102568 characters])

```js
const exampleSketch = startSketchOn("XY")
  |> startProfileAt([0, 0], %)
  |> line([10, 0], %)
  |> line([0, 10], %, $sketchingFace)
  |> line([-10, 0], %)
  |> close(%)

const example = extrude(10, exampleSketch)

const exampleSketch002 = startSketchOn(example, sketchingFace)
  |> startProfileAt([1, 1], %)
  |> line([8, 0], %)
  |> line([0, 8], %)
  |> line([-8, 0], %)
  |> close(%, $sketchingFace002)

const example002 = extrude(10, exampleSketch002)

const exampleSketch003 = startSketchOn(example002, sketchingFace002)
  |> startProfileAt([-8, 12], %)
  |> line([0, 6], %)
  |> line([6, 0], %)
  |> line([0, -6], %)
  |> close(%)

const example003 = extrude(5, exampleSketch003)
```

![Rendered example of startSketchOn 1](data:image/png;base64,[encoded data, 89356 characters])

```js
const exampleSketch = startSketchOn('XY')
  |> startProfileAt([4, 12], %)
  |> line([2, 0], %)
  |> line([0, -6], %)
  |> line([4, -6], %)
  |> line([0, -6], %)
  |> line([-3.75, -4.5], %)
  |> line([0, -5.5], %)
  |> line([-2, 0], %)
  |> close(%)

const example = revolve({ axis: 'y', angle: 180 }, exampleSketch)

const exampleSketch002 = startSketchOn(example, 'end')
  |> startProfileAt([4.5, -5], %)
  |> line([0, 5], %)
  |> line([5, 0], %)
  |> line([0, -5], %)
  |> close(%)

const example002 = extrude(5, exampleSketch002)
```

![Rendered example of startSketchOn 2](data:image/png;base64,[encoded data, 97608 characters])

```js
const a1 = startSketchOn({
       plane: {
         origin: { x: 0, y: 0, z: 0 },
         xAxis: { x: 1, y: 0, z: 0 },
         yAxis: { x: 0, y: 1, z: 0 },
         zAxis: { x: 0, y: 0, z: 1 }
       }
     })
  |> startProfileAt([0, 0], %)
  |> line([100.0, 0], %)
  |> yLine(-100.0, %)
  |> xLine(-100.0, %)
  |> yLine(100.0, %)
  |> close(%)
  |> extrude(3.14, %)
```

![Rendered example of startSketchOn 3](data:image/png;base64,[encoded data, 93312 characters])

### Arguments

* `data`: `SketchData` - Data for start sketch on. You can start a sketch on a plane or an extrude group. (REQUIRED)
```js
"XY" |
"-XY" |
"XZ" |
"-XZ" |
"YZ" |
"-YZ" |
{
	plane: {
	// Origin of the plane.
	origin: {
	x: number,
	y: number,
	z: number,
},
	// What should the plane’s X axis be?
	xAxis: {
	x: number,
	y: number,
	z: number,
},
	// What should the plane’s Y axis be?
	yAxis: {
	x: number,
	y: number,
	z: number,
},
	// The z-axis (normal).
	zAxis: {
	x: number,
	y: number,
	z: number,
},
},
} |
{
	// Chamfers or fillets on this extrude group.
	edgeCuts: [{
	// The engine id of the edge to fillet.
	edgeId: uuid,
	// The id of the engine command that called this fillet.
	id: uuid,
	radius: number,
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "fillet",
} |
{
	// The engine id of the edge to chamfer.
	edgeId: uuid,
	// The id of the engine command that called this chamfer.
	id: uuid,
	length: number,
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "chamfer",
}],
	// The id of the extrusion end cap
	endCapId: uuid,
	// The height of the extrude group.
	height: number,
	// The id of the extrude group.
	id: uuid,
	// The sketch group.
	sketchGroup: {
	// The id of the sketch group (this will change when the engine's reference to it changes.
	id: uuid,
	// What the sketch is on (can be a plane or a face).
	on: {
	// The id of the plane.
	id: uuid,
	// Origin of the plane.
	origin: {
	x: number,
	y: number,
	z: number,
},
	type: "plane",
	// Type for a plane.
	value: "XY" | "XZ" | "YZ" | "Custom",
	// What should the plane’s X axis be?
	xAxis: {
	x: number,
	y: number,
	z: number,
},
	// What should the plane’s Y axis be?
	yAxis: {
	x: number,
	y: number,
	z: number,
},
	// The z-axis (normal).
	zAxis: {
	x: number,
	y: number,
	z: number,
},
} |
{
	// The extrude group the face is on.
	extrudeGroup: ExtrudeGroup,
	// The id of the face.
	id: uuid,
	type: "face",
	// The tag of the face.
	value: string,
	// What should the face’s X axis be?
	xAxis: {
	x: number,
	y: number,
	z: number,
},
	// What should the face’s Y axis be?
	yAxis: {
	x: number,
	y: number,
	z: number,
},
	// The z-axis (normal).
	zAxis: {
	x: number,
	y: number,
	z: number,
},
},
	// The starting path.
	start: {
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
},
	// Tag identifiers that have been declared in this sketch group.
	tags: {
},
	// The paths in the sketch group.
	value: [{
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "ToPoint",
} |
{
	// arc's direction
	ccw: bool,
	// the arc's center
	center: [number, number],
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "TangentialArcTo",
} |
{
	// arc's direction
	ccw: bool,
	// the arc's center
	center: [number, number],
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "TangentialArc",
} |
{
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "Horizontal",
	// The x coordinate.
	x: number,
} |
{
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "AngledLineTo",
	// The x coordinate.
	x: number,
	// The y coordinate.
	y: number,
} |
{
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "Base",
}],
},
	// The id of the extrusion start cap
	startCapId: uuid,
	// The extrude surfaces.
	value: [{
	// The face id for the extrude plane.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "extrudePlane",
} |
{
	// The face id for the extrude plane.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "extrudeArc",
} |
{
	// The id for the chamfer surface.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "chamfer",
} |
{
	// The id for the fillet surface.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "fillet",
}],
}
```
* `tag`: `FaceTag` - A tag for a face. (OPTIONAL)
```js
"start" | "end" |
{
	// Engine information for a tag.
	info: {
	// The id of the tagged object.
	id: uuid,
	// The path the tag is on.
	path: {
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
},
	// The sketch group the tag is on.
	sketchGroup: uuid,
	// The surface information for the tag.
	surface: {
	// The face id for the extrude plane.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "extrudePlane",
} |
{
	// The face id for the extrude plane.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "extrudeArc",
} |
{
	// The id for the chamfer surface.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "chamfer",
} |
{
	// The id for the fillet surface.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "fillet",
},
},
	value: string,
}
```

### Returns

`SketchSurface` - A sketch group type.
```js
{
	// The id of the plane.
	id: uuid,
	// Origin of the plane.
	origin: {
	x: number,
	y: number,
	z: number,
},
	type: "plane",
	// Type for a plane.
	value: "XY" | "XZ" | "YZ" | "Custom",
	// What should the plane’s X axis be?
	xAxis: {
	x: number,
	y: number,
	z: number,
},
	// What should the plane’s Y axis be?
	yAxis: {
	x: number,
	y: number,
	z: number,
},
	// The z-axis (normal).
	zAxis: {
	x: number,
	y: number,
	z: number,
},
} |
{
	// The extrude group the face is on.
	extrudeGroup: {
	// Chamfers or fillets on this extrude group.
	edgeCuts: [{
	// The engine id of the edge to fillet.
	edgeId: uuid,
	// The id of the engine command that called this fillet.
	id: uuid,
	radius: number,
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "fillet",
} |
{
	// The engine id of the edge to chamfer.
	edgeId: uuid,
	// The id of the engine command that called this chamfer.
	id: uuid,
	length: number,
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "chamfer",
}],
	// The id of the extrusion end cap
	endCapId: uuid,
	// The height of the extrude group.
	height: number,
	// The id of the extrude group.
	id: uuid,
	// The sketch group.
	sketchGroup: {
	// The id of the sketch group (this will change when the engine's reference to it changes.
	id: uuid,
	// What the sketch is on (can be a plane or a face).
	on: {
	// The id of the plane.
	id: uuid,
	// Origin of the plane.
	origin: {
	x: number,
	y: number,
	z: number,
},
	type: "plane",
	// Type for a plane.
	value: "XY" | "XZ" | "YZ" | "Custom",
	// What should the plane’s X axis be?
	xAxis: {
	x: number,
	y: number,
	z: number,
},
	// What should the plane’s Y axis be?
	yAxis: {
	x: number,
	y: number,
	z: number,
},
	// The z-axis (normal).
	zAxis: {
	x: number,
	y: number,
	z: number,
},
} |
{
	// The extrude group the face is on.
	extrudeGroup: ExtrudeGroup,
	// The id of the face.
	id: uuid,
	type: "face",
	// The tag of the face.
	value: string,
	// What should the face’s X axis be?
	xAxis: {
	x: number,
	y: number,
	z: number,
},
	// What should the face’s Y axis be?
	yAxis: {
	x: number,
	y: number,
	z: number,
},
	// The z-axis (normal).
	zAxis: {
	x: number,
	y: number,
	z: number,
},
},
	// The starting path.
	start: {
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
},
	// Tag identifiers that have been declared in this sketch group.
	tags: {
},
	// The paths in the sketch group.
	value: [{
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "ToPoint",
} |
{
	// arc's direction
	ccw: bool,
	// the arc's center
	center: [number, number],
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "TangentialArcTo",
} |
{
	// arc's direction
	ccw: bool,
	// the arc's center
	center: [number, number],
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "TangentialArc",
} |
{
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "Horizontal",
	// The x coordinate.
	x: number,
} |
{
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "AngledLineTo",
	// The x coordinate.
	x: number,
	// The y coordinate.
	y: number,
} |
{
	// The from point.
	from: [number, number],
	// The tag of the path.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	// The to point.
	to: [number, number],
	type: "Base",
}],
},
	// The id of the extrusion start cap
	startCapId: uuid,
	// The extrude surfaces.
	value: [{
	// The face id for the extrude plane.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "extrudePlane",
} |
{
	// The face id for the extrude plane.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "extrudeArc",
} |
{
	// The id for the chamfer surface.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "chamfer",
} |
{
	// The id for the fillet surface.
	faceId: uuid,
	// The id of the geometry.
	id: uuid,
	// The source range.
	sourceRange: [number, number],
	// The tag.
	tag: {
	digest: [number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number, number],
	end: number,
	start: number,
	value: string,
},
	type: "fillet",
}],
},
	// The id of the face.
	id: uuid,
	type: "face",
	// The tag of the face.
	value: string,
	// What should the face’s X axis be?
	xAxis: {
	x: number,
	y: number,
	z: number,
},
	// What should the face’s Y axis be?
	yAxis: {
	x: number,
	y: number,
	z: number,
},
	// The z-axis (normal).
	zAxis: {
	x: number,
	y: number,
	z: number,
},
}
```



