PolygonShape

Artifact: androidx.compose.foundation:foundation

Cmn
```
sealed class PolygonShape : Shape
```

Defines a Shape built from rounded polygon geometry.

Create instances with PolygonShape or companion factories like regularPolygon and star.

Call transform to rotate, translate, scale, apply a Matrix, or fit the geometry into the layout bounds in place.
Call copy before mutating a shared shape to keep the original unchanged.

Note: Caches the resolved Outline for the most recent layout size, and shares returned Outline instances across callers. Do not mutate the Outline returned by createOutline.

Summary

Public companion functions
`PolygonShape`	`absoluteRectangle( topLeftRounding: CornerRounding, topRightRounding: CornerRounding, bottomRightRounding: CornerRounding, bottomLeftRounding: CornerRounding )` Creates a rectangular `PolygonShape` with fixed left/right corner roundings.	Cmn
`PolygonShape`	`circle(numVertices: @IntRange(from = 3) Int)` Creates a circular `PolygonShape` approximated by `numVertices` rounded vertices.	Cmn
`PolygonShape`	`pill(smoothing: @FloatRange(from = 0.0, to = 1.0) Float)` Creates a pill `PolygonShape` with rounded ends along the shorter container sides.	Cmn
`PolygonShape`	`pillStar( numPoints: @IntRange(from = 2) Int, innerRadiusRatio: @FloatRange(from = 0.0, to = 1.0, fromInclusive = false, toInclusive = false) Float, vertexSpacing: @FloatRange(from = 0.0, to = 1.0) Float, startLocation: @FloatRange(from = 0.0, to = 1.0) Float, outerRounding: CornerRounding, innerRounding: CornerRounding )` Creates a star `PolygonShape` with vertices distributed along a `pill` outline.	Cmn
`PolygonShape`	`rectangle(rounding: CornerRounding)` Creates a rectangular `PolygonShape` filling the layout bounds with uniform `rounding`.	Cmn
`PolygonShape`	`rectangle( topStartRounding: CornerRounding, topEndRounding: CornerRounding, bottomEndRounding: CornerRounding, bottomStartRounding: CornerRounding )` Creates a rectangular `PolygonShape` with independent layout-direction-aware corners.	Cmn
`PolygonShape`	`regularPolygon( numVertices: @IntRange(from = 3) Int, rounding: CornerRounding )` Creates a regular polygon `PolygonShape` inscribed in the container's smaller dimension.	Cmn
`PolygonShape`	`star( numPoints: @IntRange(from = 2) Int, innerRadiusRatio: @FloatRange(from = 0.0, to = 1.0, fromInclusive = false, toInclusive = false) Float, outerRounding: CornerRounding, innerRounding: CornerRounding )` Creates a star `PolygonShape` inscribed in the container's smaller dimension.	Cmn

Protected constructors
`PolygonShape()`	Cmn

Public functions
`PolygonShape`	`@RememberInComposition copy()` Creates an independent copy of this `PolygonShape` and its transformations.	Cmn
`final Outline`	`createOutline( size: Size, layoutDirection: LayoutDirection, density: Density )` Creates `Outline` of this shape for the given `size`.	Cmn
`Unit`	`@RememberInComposition transform(block: PolygonShapeTransformScope.() -> Unit)` Transforms this `PolygonShape`'s geometry in place using `block`.	Cmn

Public companion functions

absoluteRectangle

Cmn

Added in 1.13.0-beta01

fun absoluteRectangle(
    topLeftRounding: CornerRounding = CornerRounding.Unrounded,
    topRightRounding: CornerRounding = CornerRounding.Unrounded,
    bottomRightRounding: CornerRounding = CornerRounding.Unrounded,
    bottomLeftRounding: CornerRounding = CornerRounding.Unrounded
): PolygonShape

Creates a rectangular PolygonShape with fixed left/right corner roundings.

Corner roundings do not mirror with LayoutDirection.

Parameters
`topLeftRounding: CornerRounding = CornerRounding.Unrounded`	top-left corner rounding, resolved against the layout bounds
`topRightRounding: CornerRounding = CornerRounding.Unrounded`	top-right corner rounding, resolved against the layout bounds
`bottomRightRounding: CornerRounding = CornerRounding.Unrounded`	bottom-right corner rounding, resolved against the layout bounds
`bottomLeftRounding: CornerRounding = CornerRounding.Unrounded`	bottom-left corner rounding, resolved against the layout bounds

circle

Cmn

Added in 1.13.0-beta01

fun circle(numVertices: @IntRange(from = 3) Int = 8): PolygonShape

Creates a circular PolygonShape approximated by numVertices rounded vertices.

Parameters
`numVertices: @IntRange(from = 3) Int = 8`	number of vertices approximating the circle, at least 3

Throws
`IllegalArgumentException`	if `numVertices` is less than 3

pill

Cmn

Added in 1.13.0-beta01

fun pill(smoothing: @FloatRange(from = 0.0, to = 1.0) Float = 0.0f): PolygonShape

Creates a pill PolygonShape with rounded ends along the shorter container sides.

Parameters
`smoothing: @FloatRange(from = 0.0, to = 1.0) Float = 0.0f`	transition smoothness between the endcap arcs and straight edges, in `0f..1f` (`0f` keeps a purely circular arc)

Throws
`IllegalArgumentException`	if `smoothing` is outside `0f..1f`

pillStar

Cmn

Added in 1.13.0-beta01

fun pillStar(
    numPoints: @IntRange(from = 2) Int,
    innerRadiusRatio: @FloatRange(from = 0.0, to = 1.0, fromInclusive = false, toInclusive = false) Float = 0.5f,
    vertexSpacing: @FloatRange(from = 0.0, to = 1.0) Float = 0.5f,
    startLocation: @FloatRange(from = 0.0, to = 1.0) Float = 0.0f,
    outerRounding: CornerRounding = CornerRounding.Unrounded,
    innerRounding: CornerRounding = outerRounding
): PolygonShape

Creates a star PolygonShape with vertices distributed along a pill outline.

vertexSpacing controls how vertices are spaced around the curved ends:

0f: spaces inner vertices evenly along the curved ends
1f: spaces outer vertices evenly along the curved ends
0.5f (default): averages inner and outer spacing symmetrically

import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.shape.CornerRounding
import androidx.compose.foundation.shape.PolygonShape
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

// An elongated star outline distributed along a pill container, creating a decorative badge.
val pillStar = remember {
    PolygonShape.pillStar(
        numPoints = 8,
        innerRadiusRatio = 0.6f,
        outerRounding = CornerRounding.fraction(0.2f, smoothing = 0.5f),
    )
}
Box(Modifier.size(width = 140.dp, height = 64.dp).clip(pillStar).background(Color(0xFFE91E63)))

Parameters
`numPoints: @IntRange(from = 2) Int`	number of star tips, at least 2
`innerRadiusRatio: @FloatRange(from = 0.0, to = 1.0, fromInclusive = false, toInclusive = false) Float = 0.5f`	ratio of inner radius to outer radius, in `(0f, 1f)`
`vertexSpacing: @FloatRange(from = 0.0, to = 1.0) Float = 0.5f`	curved-end vertex spacing policy, in `0f..1f`
`startLocation: @FloatRange(from = 0.0, to = 1.0) Float = 0.0f`	perimeter offset where the outline starts, in `0f..1f`
`outerRounding: CornerRounding = CornerRounding.Unrounded`	rounding for outer tips, resolved against the star's outer radius
`innerRounding: CornerRounding = outerRounding`	rounding for inner corners, resolved against the star's outer radius

Throws
`IllegalArgumentException`	if `numPoints` is less than 2, `innerRadiusRatio` is outside `(0f, 1f)`, or `vertexSpacing` or `startLocation` is outside `0f..1f`

rectangle

Cmn

Added in 1.13.0-beta01

fun rectangle(rounding: CornerRounding): PolygonShape

Creates a rectangular PolygonShape filling the layout bounds with uniform rounding.

Parameters
`rounding: CornerRounding`	corner rounding for all 4 corners, resolved against the layout bounds

rectangle

Cmn

Added in 1.13.0-beta01

fun rectangle(
    topStartRounding: CornerRounding = CornerRounding.Unrounded,
    topEndRounding: CornerRounding = CornerRounding.Unrounded,
    bottomEndRounding: CornerRounding = CornerRounding.Unrounded,
    bottomStartRounding: CornerRounding = CornerRounding.Unrounded
): PolygonShape

Creates a rectangular PolygonShape with independent layout-direction-aware corners.

Corner roundings mirror automatically in LayoutDirection.Rtl.

Parameters
`topStartRounding: CornerRounding = CornerRounding.Unrounded`	top-start corner rounding, resolved against the layout bounds
`topEndRounding: CornerRounding = CornerRounding.Unrounded`	top-end corner rounding, resolved against the layout bounds
`bottomEndRounding: CornerRounding = CornerRounding.Unrounded`	bottom-end corner rounding, resolved against the layout bounds
`bottomStartRounding: CornerRounding = CornerRounding.Unrounded`	bottom-start corner rounding, resolved against the layout bounds

regularPolygon

Cmn

Added in 1.13.0-beta01

fun regularPolygon(
    numVertices: @IntRange(from = 3) Int,
    rounding: CornerRounding = CornerRounding.Unrounded
): PolygonShape

Creates a regular polygon PolygonShape inscribed in the container's smaller dimension.

import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.shape.CornerRounding
import androidx.compose.foundation.shape.PolygonShape
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

// A pentagon whose corners round to a 0.2f fraction of its generating radius, so the rounding
// scales proportionally with the shape at any size.
val pentagon = remember {
    PolygonShape.regularPolygon(numVertices = 5, rounding = CornerRounding.fraction(0.2f))
}
Box(Modifier.size(96.dp).clip(pentagon).background(Color(0xFF009688)))

Parameters
`numVertices: @IntRange(from = 3) Int`	number of vertices, at least 3
`rounding: CornerRounding = CornerRounding.Unrounded`	corner rounding resolved against the polygon's radius

Throws
`IllegalArgumentException`	if `numVertices` is less than 3

star

Cmn

Added in 1.13.0-beta01

fun star(
    numPoints: @IntRange(from = 2) Int,
    innerRadiusRatio: @FloatRange(from = 0.0, to = 1.0, fromInclusive = false, toInclusive = false) Float = 0.5f,
    outerRounding: CornerRounding = CornerRounding.Unrounded,
    innerRounding: CornerRounding = outerRounding
): PolygonShape

Creates a star PolygonShape inscribed in the container's smaller dimension.

import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.shape.CornerRounding
import androidx.compose.foundation.shape.PolygonShape
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

// An eight-point star with smoothly rounded outer points.
val star =
    PolygonShape.star(
        numPoints = 8,
        innerRadiusRatio = 0.6f,
        outerRounding = CornerRounding.fraction(0.15f, smoothing = 0.5f),
    )
Box(Modifier.size(96.dp).clip(star).background(Color(0xFFFFC107)))

Parameters
`numPoints: @IntRange(from = 2) Int`	number of star tips, at least 2
`innerRadiusRatio: @FloatRange(from = 0.0, to = 1.0, fromInclusive = false, toInclusive = false) Float = 0.5f`	ratio of inner radius to outer radius, in `(0f, 1f)`
`outerRounding: CornerRounding = CornerRounding.Unrounded`	rounding for outer tips, resolved against the star's outer radius
`innerRounding: CornerRounding = outerRounding`	rounding for inner corners, resolved against the star's outer radius

Throws
`IllegalArgumentException`	if `numPoints` is less than 2 or `innerRadiusRatio` is outside `(0f, 1f)`

Protected constructors

PolygonShape

Cmn

protected PolygonShape()

Public functions

copy

Cmn

Added in 1.13.0-beta01

@RememberInComposition
fun copy(): PolygonShape

Creates an independent copy of this PolygonShape and its transformations.

Subsequent in-place mutations via transform on the returned copy do not affect this shape, and vice versa.

import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.shape.CornerRounding
import androidx.compose.foundation.shape.PolygonShape
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

// Creates an unrotated badge shape and an independent rotated copy using copy() + transform {}.
val badge = remember {
    PolygonShape.star(
        numPoints = 8,
        innerRadiusRatio = 0.75f,
        outerRounding = CornerRounding.fraction(0.4f),
    )
}
val selectedBadge =
    remember(badge) { badge.copy().apply { transform { rotate(degrees = 22.5f) } } }
var selected by remember { mutableStateOf(false) }
val shape = if (selected) selectedBadge else badge
Box(
    Modifier.size(96.dp).clip(shape).background(Color(0xFF00695C)).clickable {
        selected = !selected
    }
)

Returns
`PolygonShape`	a new `PolygonShape` with the same base geometry and transformation configuration

createOutline

Cmn

Added in 1.13.0-beta01

final fun createOutline(
    size: Size,
    layoutDirection: LayoutDirection,
    density: Density
): Outline

Creates Outline of this shape for the given size.

Parameters
`size: Size`	the size of the shape boundary.
`layoutDirection: LayoutDirection`	the current layout direction.
`density: Density`	the current density of the screen.

Returns
`Outline`	`Outline` of this shape for the given `size`.

transform

Cmn

Added in 1.13.0-beta01

@RememberInComposition
fun transform(block: PolygonShapeTransformScope.() -> Unit): Unit

Transforms this PolygonShape's geometry in place using block.

Runs block in PolygonShapeTransformScope during outline resolution, deferring Compose state reads out of composition so animated transforms update without recomposition.
Replaces any transformation block previously set on this shape via transform.
Mutates this PolygonShape in place; call copy first to keep a shared base shape unchanged.

import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.shape.CornerRounding
import androidx.compose.foundation.shape.PolygonShape
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.layout.ContentScale
import androidx.compose.ui.unit.dp

// A square polygon rotated 45 degrees around its center and scaled into the layout bounds in a
// single pass so the rotated diamond stays inscribed without clipping.
val diamond = remember {
    PolygonShape { polygon(numVertices = 4, rounding = CornerRounding.fraction(0.15f)) }
        .apply {
            transform {
                rotate(degrees = 45f)
                scaleToFit(contentScale = ContentScale.Fit)
            }
        }
}
Box(Modifier.size(96.dp).clip(diamond).background(Color(0xFFE91E63)))

import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.shape.CornerRounding
import androidx.compose.foundation.shape.PolygonShape
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp

// Creates an unrotated badge shape and an independent rotated copy using copy() + transform {}.
val badge = remember {
    PolygonShape.star(
        numPoints = 8,
        innerRadiusRatio = 0.75f,
        outerRounding = CornerRounding.fraction(0.4f),
    )
}
val selectedBadge =
    remember(badge) { badge.copy().apply { transform { rotate(degrees = 22.5f) } } }
var selected by remember { mutableStateOf(false) }
val shape = if (selected) selectedBadge else badge
Box(
    Modifier.size(96.dp).clip(shape).background(Color(0xFF00695C)).clickable {
        selected = !selected
    }
)

Parameters
`block: PolygonShapeTransformScope.() -> Unit`	transformation block run in `PolygonShapeTransformScope` at resolution time