Heatmap

The android-heatmap module provides a map-implementation-agnostic heatmap overlay for MapConductor. It renders heatmap data as a tile-based raster layer and works with any map provider (Google Maps, MapLibre, Mapbox, ArcGIS, HERE, etc.).

Installation

dependencies {
    implementation(platform("com.mapconductor:mapconductor-bom:1.1.3"))
    implementation("com.mapconductor:core")
    implementation("com.mapconductor:heatmap")

    // Choose your map provider
    implementation("com.mapconductor:for-googlemaps")
}

Basic Usage

Place HeatmapOverlay inside any XxxMapView content block and add points with HeatmapPoint:

XxxMapView(...) {
    HeatmapOverlay(
        radiusPx = 20,
        opacity = 0.7,
    ) {
        HeatmapPoint(
            position = GeoPoint(latitude = 35.6762, longitude = 139.6503),
            weight = 1.0,
        )
        HeatmapPoint(
            position = GeoPoint(latitude = 35.6895, longitude = 139.6917),
            weight = 2.5,
        )
    }
}

Batch Points

For large datasets, use HeatmapPoints to add all points in a single update:

val pointStates: List<HeatmapPointState> = remember { buildPointList() }

XxxMapView(...) {
    HeatmapOverlay(radiusPx = 20) {
        HeatmapPoints(pointStates)
    }
}

Dynamic State

Use HeatmapOverlayState to control heatmap properties at runtime:

val heatmapState = remember {
    HeatmapOverlayState(
        radiusPx = 20,
        opacity = 0.7,
        gradient = HeatmapGradient.DEFAULT,
    )
}

// Update dynamically
heatmapState.radiusPx = 30
heatmapState.opacity = 0.5

XxxMapView(...) {
    HeatmapOverlay(state = heatmapState) {
        HeatmapPoints(pointStates)
    }
}

Custom Gradient

val gradient = HeatmapGradient(
    listOf(
        HeatmapGradientStop(position = 0.0, color = Color.argb(0, 0, 0, 255)),
        HeatmapGradientStop(position = 0.5, color = Color.rgb(0, 255, 0)),
        HeatmapGradientStop(position = 1.0, color = Color.rgb(255, 0, 0)),
    )
)

val heatmapState = remember {
    HeatmapOverlayState(gradient = gradient)
}

API Reference

HeatmapOverlay

Parameter	Type	Default	Description
radiusPx	Int	20	Blur radius of each point in pixels
opacity	Double	0.7	Layer opacity (0.0–1.0)
gradient	HeatmapGradient	HeatmapGradient.DEFAULT	Color gradient
maxIntensity	Double?	null	Max intensity for normalization; auto-calculated if null

HeatmapOverlayState

Property	Type	Default
radiusPx	Int	20
opacity	Double	0.7
gradient	HeatmapGradient	HeatmapGradient.DEFAULT
maxIntensity	Double?	null
weightProvider	(HeatmapPointState) -> Double	{ it.weight }

HeatmapGradient.DEFAULT

Green (#66E100) at position 0.2 → Red (#FF0000) at position 1.0.