Mapforge stores your maps in GeoJSON format. Below you can see the list of supported properties to style your map elements (called features in GeoJSON).
Most of the properties are supported to be changed in the UI. For changing the properties directly, you can use the Edit JSON button in the feature details modal.
Extending the Mapbox Simplestyle Spec, Mapforge supports these feature attributes:
label: Label to show on the map (no emoji support)label-size: font size (default 16, max. 254)label-font: label font array (default depends on base map, like ['noto_sans_regular'])label-color: font color in format "#000000" (default)label-justify: alignment: auto (default), left, center, rightlabel-max-width: line width (default 10)label-letter-spacing: space between letters (default 0)label-shadow: font shadow in format "#ffffff" (default)label-shadow-width: shadow width/halo width in pixels (default 2, max. 5)label-anchor: text anchor position relative to the feature: top (default), bottom, left, right, center, top-left, top-right, bottom-left, bottom-rightlabel-offset: label position offset from the anchor as [x, y] in em units (default: depends on marker size for label-anchor: top, otherwise [0, 0])sort-key: sort order of features: higher numbers overlay lower numbers (default: 1)min-zoom: Display feature only on zoom levels bigger than min-zoommax-zoom: Display feature only on zoom levels smaller than max-zoomlevel: floor the feature belongs to (e.g. "0", "1", "-1"). Accepts an OSM-style semicolon-separated list ("0;1;2") for features that span multiple floors. Features without this property are always visible.title: titledesc: detailed description (markdown supported)onclick: on hover/click behavior: 'details' (default), 'false' (do not react on hover/click), 'link' (link to url), 'feature' (link to another feature on the map)onclick-target: required for onclick=link/feature: url or feature id of targetmarker-color: circle color (default "green", 'transparent' for none)marker-size: radius of the marker (default: 6, with 'marker-symbol' fixed to 16 )marker-opacity: opacity of the marker (default: 0.7)marker-symbol: taken as text/emoji, emoji list: https://emojipedia.org/google/15.1marker-image-url: URL pointing to icon image. Can point to a Mapforge hosted image like /image/marker-color and stroke.marker-scaling: marker scales with zoom level (default: false)stroke-width: width of the circle border line (default: 2)stroke: circle border color (default "white", 'transparent' for none)heatmap: if set, points will be styled as a heatmapflat: if set, marker + label with be projected 'flat' on the mapmarker-rotate: rotate marker by x degrees clockwisestroke-width: width of the line (default: 2)stroke: line color (default: 'darkgreen')stroke-opacity: opacity of the line (default: 0.8)stroke-image-url: URL pointing to icon image that will get repeated along the line. Can point to a Mapforge hosted image like /icons/direction-arrow.pngstroke-symbol: taken as text/emoji, emoji list: https://emojipedia.org/google/16stroke-dasharray: true/false for making the stroke line dashed (default: false)fill-extrusion-color: color of the extrusion (default: green)fill-extrusion-height: height in mfill-extrusion-width: width in mfill-extrusion-base: ground distance in m (default: 0)show-km-markers: show markers at each kilometer (default: false)stroke-width: width of the line (default: 3)stroke: line color (default: 'darkgreen', 'transparent' for none)stroke-opacity: opacity of the line (default: 1.0)fill: fill color (default: "#0A870A", green, 'transparent' for none)fill-opacity: opacity of the fill color (default: 0.9)fill-extrusion-color: color of the extrusion (default: green)fill-extrusion-height: height in mfill-extrusion-base: ground distance in m (default: 0)