List of OpenLayers supported styles taken from OL 2 docs

Url to a graphic to be used as the background under an externalGraphic.

The integer z-index value to use in rendering the background graphic.

The height of the background graphic. If not provided, the graphicHeight will be used.

The width of the background width. If not provided, the graphicWidth will be used.

The x offset (in pixels) for the background graphic.

The y offset (in pixels) for the background graphic.

Default is "".

Symbolizers will have no effect if display is set to "none". All other values have no effect.

Url to an external graphic that will be used for rendering points.

Set to false if no fill is desired.

Hex fill color. Default is "#ee9900".

Fill opacity (0-1). Default is 0.4

The font color for the label, to be provided like CSS.

The font family for the label, to be provided like in CSS.

Opacity (0-1) for the label

The font size for the label, to be provided like in CSS.

The font style for the label, to be provided like in CSS.

The font weight for the label, to be provided like in CSS.

Set to false if no graphic is desired.

Pixel height for sizing an external graphic.

Named graphic to use when rendering points. Supported values include "circle" (default), "square", "star", "x", "cross", "triangle".

Opacity (0-1) for an external graphic.

Pixel width for sizing an external graphic.

Pixel offset along the positive x axis for displacing an external graphic.

Pixel offset along the positive y axis for displacing an external graphic.

The integer z-index value to use in rendering.

The text for an optional label. For browsers that use the canvas renderer, this requires either fillText or mozDrawText to be available.

Label alignment. This specifies the insertion point relative to the text. It is a string composed of two characters. The first character is for the horizontal alignment, the second for the vertical alignment. Valid values for horizontal alignment: "l"=left, "c"=center, "r"=right. Valid values for vertical alignment: "t"=top, "m"=middle, "b"=bottom. Example values: "lt", "cm", "rb". Default is "cm".

The color of the label outline. Default is 'white'. Only supported by the canvas & SVG renderers.

The opacity (0-1) of the label outline. Default is fontOpacity. Only supported by the canvas & SVG renderers.

The width of the label outline. Default is 3, set to 0 or null to disable. Only supported by the SVG renderers.

If set to true, labels will be selectable using SelectFeature or similar controls. Default is false.

Pixel offset along the positive x axis for displacing the label. Not supported by the canvas renderer.

Pixel offset along the positive y axis for displacing the label. Not supported by the canvas renderer.

Pixel point radius. Default is 6.

Default is "visiblePainted".

For point symbolizers, this is the rotation of a graphic in the clockwise direction about its center point (or any point off center as specified by graphicXOffset and graphicYOffset).

Set to false if no stroke is desired.

Hex stroke color. Default is "#ee9900".

Stroke dash style. Default is "solid". [dot | dash | dashdot | longdash | longdashdot | solid]

Stroke cap type. Default is "round". [butt | round | square]

Stroke opacity (0-1). Default is 1.

Pixel stroke width. Default is 1.

Tooltip when hovering over a feature. Not supported by the canvas renderer.

interface FeatureStyle {
    backgroundGraphic?: string;
    backgroundGraphicZIndex?: number;
    backgroundHeight?: string | number;
    backgroundWidth?: string | number;
    backgroundXOffset?: string | number;
    backgroundYOffset?: string | number;
    cursor?: string;
    display?: string;
    externalGraphic?: null | string;
    fill?: boolean;
    fillColor?: string;
    fillOpacity?: number;
    fontColor?: string;
    fontFamily?: string;
    fontOpacity?: number;
    fontSize?: string;
    fontStyle?: string;
    fontWeight?: string;
    graphic?: boolean;
    graphicHeight?: string | number;
    graphicName?: string;
    graphicOpacity?: string | number;
    graphicWidth?: string | number;
    graphicXOffset?: number;
    graphicYOffset?: string | number;
    graphicZIndex?: string | number;
    hoverFillColor?: string;
    hoverFillOpacity?: number;
    hoverPointRadius?: number;
    hoverPointUnit?: string;
    hoverStrokeColor?: string;
    hoverStrokeOpacity?: number;
    hoverStrokeWidth?: number;
    label?: string;
    labelAlign?: string;
    labelOutlineColor?: string;
    labelOutlineOpacity?: number;
    labelOutlineWidth?: number;
    labelSelect?: boolean;
    labelXOffset?: number;
    labelYOffset?: number;
    pointerEvents?: string;
    pointRadius?: string | number;
    rotation?: string | number;
    stroke?: boolean;
    strokeColor?: string;
    strokeDashstyle?:
        | "solid"
        | "dot"
        | "dash"
        | "dashdot"
        | "longdash"
        | "longdashdot";
    strokeLinecap?: "butt"
    | "round"
    | "square";
    strokeOpacity?: string | number;
    strokeWidth?: string | number;
    title?: string;
}

Properties

backgroundGraphic?: string
backgroundGraphicZIndex?: number
backgroundHeight?: string | number
backgroundWidth?: string | number
backgroundXOffset?: string | number
backgroundYOffset?: string | number
cursor?: string
display?: string
externalGraphic?: null | string
fill?: boolean
fillColor?: string
fillOpacity?: number
fontColor?: string
fontFamily?: string
fontOpacity?: number
fontSize?: string
fontStyle?: string
fontWeight?: string
graphic?: boolean
graphicHeight?: string | number
graphicName?: string
graphicOpacity?: string | number
graphicWidth?: string | number
graphicXOffset?: number
graphicYOffset?: string | number
graphicZIndex?: string | number
hoverFillColor?: string
hoverFillOpacity?: number
hoverPointRadius?: number
hoverPointUnit?: string
hoverStrokeColor?: string
hoverStrokeOpacity?: number
hoverStrokeWidth?: number
label?: string
labelAlign?: string
labelOutlineColor?: string
labelOutlineOpacity?: number
labelOutlineWidth?: number
labelSelect?: boolean
labelXOffset?: number
labelYOffset?: number
pointerEvents?: string
pointRadius?: string | number
rotation?: string | number
stroke?: boolean
strokeColor?: string
strokeDashstyle?:
    | "solid"
    | "dot"
    | "dash"
    | "dashdot"
    | "longdash"
    | "longdashdot"
strokeLinecap?: "butt" | "round" | "square"
strokeOpacity?: string | number
strokeWidth?: string | number
title?: string