PolygonShapeScope

Artifact: androidx.compose.foundation:foundation

View Source

Added in 1.13.0-alpha03

Common/All

• Cmn

  sealed interface PolygonShapeScope : Density

---

Receiver scope for the PolygonShape builder lambda.

Provides the resolution inputs (size, layoutDirection, and Density) and the factories that create the PolygonShapeGeometry the lambda returns. Coordinates are in pixels in the layout's coordinate space; Dp values resolve with the current density, and percent values are size-proportional.

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

// A regular hexagon sized to the container's smaller dimension with an exact 16.dp corner
// rounding resolved against the current density.
val hexagon = remember {
    PolygonShape {
        polygon(
            numVertices = 6,
            radius = size.minDimension / 2f,
            center = Offset(size.width / 2f, size.height / 2f),
            rounding = CornerRounding(radius = 16.dp),
        )
    }
}
Box(Modifier.size(96.dp).clip(hexagon).background(Color(0xFF3F51B5)))

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

// A pointed tag whose arrow tip adapts to the layout size and flips horizontally in RTL.
val tag = remember {
    PolygonShape {
        val isLtr = layoutDirection == LayoutDirection.Ltr
        val tipX = if (isLtr) size.width else 0f
        val baseX = if (isLtr) 0f else size.width
        val indentX = if (isLtr) size.width * 0.2f else size.width * 0.8f
        polygon(
            vertices =
                listOf(
                    Offset(baseX, 0f),
                    Offset(tipX, size.height / 2f),
                    Offset(baseX, size.height),
                    Offset(indentX, size.height / 2f),
                ),
            rounding = CornerRounding(radius = 6.dp),
        )
    }
}
Box(Modifier.size(width = 120.dp, height = 64.dp).clip(tag).background(Color(0xFF4CAF50)))

Summary

Public functions
PolygonShapeGeometry	polygon(     vertices: List<Offset>,     center: Offset,     rounding: PolygonShapeGeometry.CornerRounding ) Creates polygon geometry from vertices in pixels, with the same rounding at every vertex.	Cmn
PolygonShapeGeometry	polygon(     vertices: List<Offset>,     perVertexRounding: List<PolygonShapeGeometry.CornerRounding>,     center: Offset ) Creates polygon geometry from vertices in pixels, with a separate rounding for each vertex.	Cmn
PolygonShapeGeometry	polygon(     numVertices: Int,     perVertexRounding: List<PolygonShapeGeometry.CornerRounding>,     radius: Float,     center: Offset ) Creates a regular polygon with numVertices vertices on a circle of radius pixels around center, with a separate rounding for each vertex.	Cmn
PolygonShapeGeometry	polygon(     numVertices: Int,     radius: Float,     center: Offset,     rounding: PolygonShapeGeometry.CornerRounding ) Creates a regular polygon with numVertices vertices on a circle of radius pixels around center, with the same rounding at every vertex.	Cmn

Public properties
LayoutDirection	layoutDirection Layout direction of the shape.	Cmn
Size	size Size of the shape's layout container in pixels.	Cmn

Inherited functions
From androidx.compose.ui.unit.Density open Int Dp.roundToPx() Convert Dp to Int by rounding Cmn open Int TextUnit.roundToPx() Convert Sp to Int by rounding Cmn open Dp Int.toDp() Convert an Int pixel value to Dp. Cmn open Dp Float.toDp() Convert a Float pixel value to a Dp Cmn open DpSize Size.toDpSize() Convert a Size to a DpSize. Cmn open Float Dp.toPx() Convert Dp to pixels. Cmn open Float TextUnit.toPx() Convert Sp to pixels. Cmn open Rect DpRect.toRect() Convert a DpRect to a Rect. Cmn open Size DpSize.toSize() Convert a DpSize to a Size. Cmn open TextUnit Int.toSp() Convert an Int pixel value to Sp. Cmn open TextUnit Float.toSp() Convert a Float pixel value to a Sp Cmn
From androidx.compose.ui.unit.FontScaling Dp TextUnit.toDp() Convert Sp to Dp. Cmn TextUnit Dp.toSp() Convert Dp to Sp. Cmn

Inherited properties
From androidx.compose.ui.unit.Density Float density The logical density of the display. Cmn
From androidx.compose.ui.unit.FontScaling Float fontScale Current user preference for the scaling factor for fonts. Cmn

Public functions

polygon

Cmn

Added in 1.13.0-alpha03

fun polygon(
    vertices: List<Offset>,
    center: Offset = Offset.Unspecified,
    rounding: PolygonShapeGeometry.CornerRounding = CornerRounding.Unrounded
): PolygonShapeGeometry

Creates polygon geometry from vertices in pixels, with the same rounding at every vertex.

Rounding resolves against the vertex bounds, not the container. A percent radius is a percentage of the bounds' smaller dimension, a Dp radius resolves with the current density, and a float radius is a length in pixels.

Parameters
vertices: List<Offset>	vertex positions in pixels, at least 3
center: Offset = Offset.Unspecified	polygon center in pixels, computed from the geometry when unspecified. An explicit center can be specified as a custom transformation or morphing anchor.
rounding: PolygonShapeGeometry.CornerRounding = CornerRounding.Unrounded	rounding applied to every vertex

Throws
IllegalArgumentException	if vertices has fewer than 3 entries

polygon

Cmn

Added in 1.13.0-alpha03

fun polygon(
    vertices: List<Offset>,
    perVertexRounding: List<PolygonShapeGeometry.CornerRounding>,
    center: Offset = Offset.Unspecified
): PolygonShapeGeometry

Creates polygon geometry from vertices in pixels, with a separate rounding for each vertex.

Rounding resolves against the vertex bounds, not the container. A percent radius is a percentage of the bounds' smaller dimension, a Dp radius resolves with the current density, and a float radius is a length in pixels.

Parameters
vertices: List<Offset>	vertex positions in pixels, at least 3
perVertexRounding: List<PolygonShapeGeometry.CornerRounding>	rounding for each vertex, matching vertices in size
center: Offset = Offset.Unspecified	polygon center in pixels, computed from the geometry when unspecified. An explicit center can be specified as a custom transformation or morphing anchor.

Throws
IllegalArgumentException	if vertices has fewer than 3 entries, or if perVertexRounding differs from vertices in size

polygon

Cmn

Added in 1.13.0-alpha03

fun polygon(
    numVertices: Int,
    perVertexRounding: List<PolygonShapeGeometry.CornerRounding>,
    radius: Float = size.minDimension / 2f,
    center: Offset = size.center
): PolygonShapeGeometry

Creates a regular polygon with numVertices vertices on a circle of radius pixels around center, with a separate rounding for each vertex.

Rounding resolves against the polygon itself, not the container. A percent radius is a percentage of radius, a Dp radius resolves with the current density, and a float radius is a length in pixels. Vertex i of perVertexRounding rounds the vertex at angle 2πi/numVertices on the generating circle.

Parameters
numVertices: Int	number of vertices, at least 3
perVertexRounding: List<PolygonShapeGeometry.CornerRounding>	rounding for each vertex, matching numVertices in size
radius: Float = size.minDimension / 2f	radius in pixels of the circle the vertices are placed on
center: Offset = size.center	center of the polygon in pixels, defaults to the container center

Throws
IllegalArgumentException	if numVertices is less than 3, or if perVertexRounding differs from numVertices in size

polygon

Cmn

Added in 1.13.0-alpha03

fun polygon(
    numVertices: Int,
    radius: Float = size.minDimension / 2f,
    center: Offset = size.center,
    rounding: PolygonShapeGeometry.CornerRounding = CornerRounding.Unrounded
): PolygonShapeGeometry

Creates a regular polygon with numVertices vertices on a circle of radius pixels around center, with the same rounding at every vertex.

Rounding resolves against the polygon itself, not the container. A percent radius is a percentage of radius, a Dp radius resolves with the current density, and a float radius is a length in pixels.

Parameters
numVertices: Int	number of vertices, at least 3
radius: Float = size.minDimension / 2f	radius in pixels of the circle the vertices are placed on
center: Offset = size.center	center of the polygon in pixels, defaults to the container center
rounding: PolygonShapeGeometry.CornerRounding = CornerRounding.Unrounded	rounding applied to every vertex

Throws
IllegalArgumentException	if numVertices is less than 3

Public properties

layoutDirection

Cmn

Added in 1.13.0-alpha03

val layoutDirection: LayoutDirection

Layout direction of the shape.

size

Cmn

val size: Size

Size of the shape's layout container in pixels.