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SymbolLayer.md

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<MapLibreGL.SymbolLayer />

SymbolLayer is a style layer that renders icon and text labels at points or along lines on the map.

Props

Prop Type Default Required Description
style SymbolLayerStyleProps none false Customizable style attributes
children ReactElement | ReactElement[] none false @deprecated passed children used to create an image with id of symbol in style and also set the iconImageName property accordingly.
This is now deprecated, use Image component instead.
sourceID FIX ME UNKNOWN TYPE MapLibreRN.StyleSource.DefaultSourceID false FIX ME NO DESCRIPTION

Styles

symbolPlacement

Label placement relative to its geometry.

Type
enum
Default Value
point
Supported Values
  • point: The label is placed at the point where the geometry is located.
  • line: The label is placed along the line of the geometry. Can only be used on `LineString` and `Polygon` geometries.
  • line-center: The label is placed at the center of the line of the geometry. Can only be used on `LineString` and `Polygon` geometries. Note that a single feature in a vector tile may contain multiple line geometries.
Expression Parameters
zoom

symbolSpacing

Distance between two symbol anchors.

Type
number
Default Value
250
Units
pixels
Minimum
1
Expression Parameters
zoom

symbolAvoidEdges

If true, the symbols will not cross tile edges to avoid mutual collisions. Recommended in layers that don't have enough padding in the vector tile to prevent collisions, or if it is a point symbol layer placed after a line symbol layer. When using a client that supports global collision detection, like MapLibre GL JS version 0.42.0 or greater, enabling this property is not needed to prevent clipped labels at tile boundaries.

Type
boolean
Default Value
false
Expression Parameters
zoom

symbolSortKey

Sorts features in ascending order based on this value. Features with lower sort keys are drawn and placed first. When iconAllowOverlap or textAllowOverlap is false, features with a lower sort key will have priority during placement. When iconAllowOverlap or textAllowOverlap is set to true, features with a higher sort key will overlap over features with a lower sort key.

Type
number
Expression Parameters
zoom, feature

symbolZOrder

Determines whether overlapping symbols in the same layer are rendered in the order that they appear in the data source or by their yPosition relative to the viewport. To control the order and prioritization of symbols otherwise, use symbolSortKey.

Type
enum
Default Value
auto
Supported Values
  • auto: Sorts symbols by `symbol-sort-key` if set. Otherwise, sorts symbols by their y-position relative to the viewport if `icon-allow-overlap` or `text-allow-overlap` is set to `true` or `icon-ignore-placement` or `text-ignore-placement` is `false`.
  • viewport-y: Sorts symbols by their y-position relative to the viewport if `icon-allow-overlap` or `text-allow-overlap` is set to `true` or `icon-ignore-placement` or `text-ignore-placement` is `false`.
  • source: Sorts symbols by `symbol-sort-key` if set. Otherwise, no sorting is applied; symbols are rendered in the same order as the source data.
Expression Parameters
zoom

iconAllowOverlap

If true, the icon will be visible even if it collides with other previously drawn symbols.

Type
boolean
Default Value
false
Requires
iconImage
Disabled By
iconOverlap
Expression Parameters
zoom

iconIgnorePlacement

If true, other symbols can be visible even if they collide with the icon.

Type
boolean
Default Value
false
Requires
iconImage
Expression Parameters
zoom

iconOptional

If true, text will display without their corresponding icons when the icon collides with other symbols and the text does not.

Type
boolean
Default Value
false
Requires
iconImage, textField
Expression Parameters
zoom

iconRotationAlignment

In combination with symbolPlacement, determines the rotation behavior of icons.

Type
enum
Default Value
auto
Supported Values
  • map: When `symbol-placement` is set to `point`, aligns icons east-west. When `symbol-placement` is set to `line` or `line-center`, aligns icon x-axes with the line.
  • viewport: Produces icons whose x-axes are aligned with the x-axis of the viewport, regardless of the value of `symbol-placement`.
  • auto: When `symbol-placement` is set to `point`, this is equivalent to `viewport`. When `symbol-placement` is set to `line` or `line-center`, this is equivalent to `map`.
Requires
iconImage
Expression Parameters
zoom

iconSize

Scales the original size of the icon by the provided factor. The new pixel size of the image will be the original pixel size multiplied by iconSize. 1 is the original size; 3 triples the size of the image.

Type
number
Default Value
1
Units
factor of the original icon size
Minimum
0
Requires
iconImage
Expression Parameters
zoom, feature

iconTextFit

Scales the icon to fit around the associated text.

Type
enum
Default Value
none
Supported Values
  • none: The icon is displayed at its intrinsic aspect ratio.
  • width: The icon is scaled in the x-dimension to fit the width of the text.
  • height: The icon is scaled in the y-dimension to fit the height of the text.
  • both: The icon is scaled in both x- and y-dimensions.
Requires
iconImage, textField
Expression Parameters
zoom

iconTextFitPadding

Size of the additional area added to dimensions determined by iconTextFit, in clockwise order: top, right, bottom, left.

Type
array
Default Value
[0,0,0,0]
Units
pixels
Requires
iconImage, textField
Expression Parameters
zoom

iconImage

Name of image in sprite to use for drawing an image background.

Type
resolvedImage
Expression Parameters
zoom, feature

iconRotate

Rotates the icon clockwise.

Type
number
Default Value
0
Units
degrees
Requires
iconImage
Expression Parameters
zoom, feature

iconPadding

Size of additional area round the icon bounding box used for detecting symbol collisions.

Type
array
Default Value
[2]
Units
pixels
Requires
iconImage
Expression Parameters
zoom, feature

iconKeepUpright

If true, the icon may be flipped to prevent it from being rendered upsideDown.

Type
boolean
Default Value
false
Requires
iconImage
Expression Parameters
zoom

iconOffset

Offset distance of icon from its anchor. Positive values indicate right and down, while negative values indicate left and up. Each component is multiplied by the value of iconSize to obtain the final offset in pixels. When combined with iconRotate the offset will be as if the rotated direction was up.

Type
array
Default Value
[0,0]
Requires
iconImage
Expression Parameters
zoom, feature

iconAnchor

Part of the icon placed closest to the anchor.

Type
enum
Default Value
center
Supported Values
  • center: The center of the icon is placed closest to the anchor.
  • left: The left side of the icon is placed closest to the anchor.
  • right: The right side of the icon is placed closest to the anchor.
  • top: The top of the icon is placed closest to the anchor.
  • bottom: The bottom of the icon is placed closest to the anchor.
  • top-left: The top left corner of the icon is placed closest to the anchor.
  • top-right: The top right corner of the icon is placed closest to the anchor.
  • bottom-left: The bottom left corner of the icon is placed closest to the anchor.
  • bottom-right: The bottom right corner of the icon is placed closest to the anchor.
Requires
iconImage
Expression Parameters
zoom, feature

iconPitchAlignment

Orientation of icon when map is pitched.

Type
enum
Default Value
auto
Supported Values
  • map: The icon is aligned to the plane of the map.
  • viewport: The icon is aligned to the plane of the viewport.
  • auto: Automatically matches the value of `icon-rotation-alignment`.
Requires
iconImage
Expression Parameters
zoom

textPitchAlignment

Orientation of text when map is pitched.

Type
enum
Default Value
auto
Supported Values
  • map: The text is aligned to the plane of the map.
  • viewport: The text is aligned to the plane of the viewport.
  • auto: Automatically matches the value of `text-rotation-alignment`.
Requires
textField
Expression Parameters
zoom

textRotationAlignment

In combination with symbolPlacement, determines the rotation behavior of the individual glyphs forming the text.

Type
enum
Default Value
auto
Supported Values
  • map: When `symbol-placement` is set to `point`, aligns text east-west. When `symbol-placement` is set to `line` or `line-center`, aligns text x-axes with the line.
  • viewport: Produces glyphs whose x-axes are aligned with the x-axis of the viewport, regardless of the value of `symbol-placement`.
  • viewport-glyph: When `symbol-placement` is set to `point`, aligns text to the x-axis of the viewport. When `symbol-placement` is set to `line` or `line-center`, aligns glyphs to the x-axis of the viewport and places them along the line.
  • auto: When `symbol-placement` is set to `point`, this is equivalent to `viewport`. When `symbol-placement` is set to `line` or `line-center`, this is equivalent to `map`.
Requires
textField
Expression Parameters
zoom

textField

Value to use for a text label. If a plain string is provided, it will be treated as a formatted with default/inherited formatting options.

Type
formatted
Default Value
Expression Parameters
zoom, feature

textFont

Font stack to use for displaying text.

Type
array
Default Value
[Open Sans Regular,Arial Unicode MS Regular]
Requires
textField
Supported Style Functions
camera
Expression Parameters
zoom, feature

textSize

Font size.

Type
number
Default Value
16
Units
pixels
Minimum
0
Requires
textField
Expression Parameters
zoom, feature

textMaxWidth

The maximum line width for text wrapping.

Type
number
Default Value
10
Units
ems
Minimum
0
Requires
textField
Supported Style Functions
camera
Expression Parameters
zoom, feature

textLineHeight

Text leading value for multiLine text.

Type
number
Default Value
1.2
Units
ems
Requires
textField
Expression Parameters
zoom

textLetterSpacing

Text tracking amount.

Type
number
Default Value
0
Units
ems
Requires
textField
Supported Style Functions
camera
Expression Parameters
zoom, feature

textJustify

Text justification options.

Type
enum
Default Value
center
Supported Values
  • auto: The text is aligned towards the anchor position.
  • left: The text is aligned to the left.
  • center: The text is centered.
  • right: The text is aligned to the right.
Requires
textField
Supported Style Functions
camera
Expression Parameters
zoom, feature

textRadialOffset

Radial offset of text, in the direction of the symbol's anchor. Useful in combination with textVariableAnchor, which defaults to using the twoDimensional textOffset if present.

Type
number
Default Value
0
Units
ems
Requires
textField
Expression Parameters
zoom, feature

textVariableAnchor

To increase the chance of placing highPriority labels on the map, you can provide an array of textAnchor locations: the renderer will attempt to place the label at each location, in order, before moving onto the next label. Use textJustify: auto to choose justification based on anchor position. To apply an offset, use the textRadialOffset or the twoDimensional textOffset.

Type
array
Requires
textField
Expression Parameters
zoom

textAnchor

Part of the text placed closest to the anchor.

Type
enum
Default Value
center
Supported Values
  • center: The center of the text is placed closest to the anchor.
  • left: The left side of the text is placed closest to the anchor.
  • right: The right side of the text is placed closest to the anchor.
  • top: The top of the text is placed closest to the anchor.
  • bottom: The bottom of the text is placed closest to the anchor.
  • top-left: The top left corner of the text is placed closest to the anchor.
  • top-right: The top right corner of the text is placed closest to the anchor.
  • bottom-left: The bottom left corner of the text is placed closest to the anchor.
  • bottom-right: The bottom right corner of the text is placed closest to the anchor.
Requires
textField
Disabled By
textVariableAnchor
Supported Style Functions
camera
Expression Parameters
zoom, feature

textMaxAngle

Maximum angle change between adjacent characters.

Type
number
Default Value
45
Units
degrees
Requires
textField
Expression Parameters
zoom

textWritingMode

The property allows control over a symbol's orientation. Note that the property values act as a hint, so that a symbol whose language doesn’t support the provided orientation will be laid out in its natural orientation. Example: English point symbol will be rendered horizontally even if array value contains single 'vertical' enum value. The order of elements in an array define priority order for the placement of an orientation variant.

Type
array
Requires
textField
Expression Parameters
zoom

textRotate

Rotates the text clockwise.

Type
number
Default Value
0
Units
degrees
Requires
textField
Expression Parameters
zoom, feature

textPadding

Size of the additional area around the text bounding box used for detecting symbol collisions.

Type
number
Default Value
2
Units
pixels
Minimum
0
Requires
textField
Expression Parameters
zoom

textKeepUpright

If true, the text may be flipped vertically to prevent it from being rendered upsideDown.

Type
boolean
Default Value
true
Requires
textField
Expression Parameters
zoom

textTransform

Specifies how to capitalize text, similar to the CSS textTransform property.

Type
enum
Default Value
none
Supported Values
  • none: The text is not altered.
  • uppercase: Forces all letters to be displayed in uppercase.
  • lowercase: Forces all letters to be displayed in lowercase.
Requires
textField
Expression Parameters
zoom, feature

textOffset

Offset distance of text from its anchor. Positive values indicate right and down, while negative values indicate left and up. If used with textVariableAnchor, input values will be taken as absolute values. Offsets along the x and yAxis will be applied automatically based on the anchor position.

Type
array
Default Value
[0,0]
Units
ems
Requires
textField
Disabled By
textRadialOffset
Expression Parameters
zoom, feature

textAllowOverlap

If true, the text will be visible even if it collides with other previously drawn symbols.

Type
boolean
Default Value
false
Requires
textField
Disabled By
textOverlap
Expression Parameters
zoom

textIgnorePlacement

If true, other symbols can be visible even if they collide with the text.

Type
boolean
Default Value
false
Requires
textField
Expression Parameters
zoom

textOptional

If true, icons will display without their corresponding text when the text collides with other symbols and the icon does not.

Type
boolean
Default Value
false
Requires
textField, iconImage
Expression Parameters
zoom

visibility

Whether this layer is displayed.

Type
enum
Default Value
visible
Supported Values
  • visible: The layer is shown.
  • none: The layer is not shown.

iconOpacity

The opacity at which the icon will be drawn.

Type
number
Default Value
1
Minimum
0
Maximum
1
Requires
iconImage
Expression Parameters
zoom, feature, feature-state

iconOpacityTransition

The transition affecting any changes to this layer’s iconOpacity property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

iconColor

The color of the icon. This can only be used with SDF icons.

Type
color
Default Value
#000000
Requires
iconImage
Expression Parameters
zoom, feature, feature-state

iconColorTransition

The transition affecting any changes to this layer’s iconColor property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

iconHaloColor

The color of the icon's halo. Icon halos can only be used with SDF icons.

Type
color
Default Value
rgba(0, 0, 0, 0)
Requires
iconImage
Expression Parameters
zoom, feature, feature-state

iconHaloColorTransition

The transition affecting any changes to this layer’s iconHaloColor property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

iconHaloWidth

Distance of halo to the icon outline.

The unit is in pixels only for SDF sprites that were created with a blur radius of 8, multiplied by the display density. I.e., the radius needs to be 16 for @2x sprites, etc.

Type
number
Default Value
0
Units
pixels
Minimum
0
Requires
iconImage
Expression Parameters
zoom, feature, feature-state

iconHaloWidthTransition

The transition affecting any changes to this layer’s iconHaloWidth property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

iconHaloBlur

Fade out the halo towards the outside.

Type
number
Default Value
0
Units
pixels
Minimum
0
Requires
iconImage
Expression Parameters
zoom, feature, feature-state

iconHaloBlurTransition

The transition affecting any changes to this layer’s iconHaloBlur property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

iconTranslate

Distance that the icon's anchor is moved from its original placement. Positive values indicate right and down, while negative values indicate left and up.

Type
array
Default Value
[0,0]
Units
pixels
Requires
iconImage
Expression Parameters
zoom

iconTranslateTransition

The transition affecting any changes to this layer’s iconTranslate property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

iconTranslateAnchor

Controls the frame of reference for iconTranslate.

Type
enum
Default Value
map
Supported Values
  • map: Icons are translated relative to the map.
  • viewport: Icons are translated relative to the viewport.
Requires
iconImage, iconTranslate
Expression Parameters
zoom

textOpacity

The opacity at which the text will be drawn.

Type
number
Default Value
1
Minimum
0
Maximum
1
Requires
textField
Expression Parameters
zoom, feature, feature-state

textOpacityTransition

The transition affecting any changes to this layer’s textOpacity property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

textColor

The color with which the text will be drawn.

Type
color
Default Value
#000000
Requires
textField
Expression Parameters
zoom, feature, feature-state

textColorTransition

The transition affecting any changes to this layer’s textColor property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

textHaloColor

The color of the text's halo, which helps it stand out from backgrounds.

Type
color
Default Value
rgba(0, 0, 0, 0)
Requires
textField
Expression Parameters
zoom, feature, feature-state

textHaloColorTransition

The transition affecting any changes to this layer’s textHaloColor property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

textHaloWidth

Distance of halo to the font outline. Max text halo width is 1/4 of the fontSize.

Type
number
Default Value
0
Units
pixels
Minimum
0
Requires
textField
Expression Parameters
zoom, feature, feature-state

textHaloWidthTransition

The transition affecting any changes to this layer’s textHaloWidth property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

textHaloBlur

The halo's fadeout distance towards the outside.

Type
number
Default Value
0
Units
pixels
Minimum
0
Requires
textField
Expression Parameters
zoom, feature, feature-state

textHaloBlurTransition

The transition affecting any changes to this layer’s textHaloBlur property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

textTranslate

Distance that the text's anchor is moved from its original placement. Positive values indicate right and down, while negative values indicate left and up.

Type
array
Default Value
[0,0]
Units
pixels
Requires
textField
Expression Parameters
zoom

textTranslateTransition

The transition affecting any changes to this layer’s textTranslate property.

Type
{ duration, delay }
Units
milliseconds
Default Value
{duration: 300, delay: 0}

textTranslateAnchor

Controls the frame of reference for textTranslate.

Type
enum
Default Value
map
Supported Values
  • map: The text is translated relative to the map.
  • viewport: The text is translated relative to the viewport.
Requires
textField, textTranslate
Expression Parameters
zoom