commonMain.ovh.plrapps.mapcompose.core.Tile.kt Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of mapcompose-mp-desktop Show documentation

A Compose Multiplatform library to display tiled maps, with support for markers, paths, and rotation

There is a newer version: 0.9.4

Show newest version

package ovh.plrapps.mapcompose.core

import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.setValue
import androidx.compose.ui.graphics.ImageBitmap

/**
 * A [Tile] is defined by its coordinates in the "pyramid". A [Tile] is sub-sampled when the
 * scale becomes lower than the scale of the lowest level. To reflect that, there is [subSample]
 * property which is a positive integer (can be 0). When [subSample] equals 0, the [bitmap] of the
 * tile is full scale. When [subSample] equals 1, the [bitmap] is sub-sampled and its size is half
 * the original bitmap (the one at the lowest level), and so on.
 */
internal data class Tile(
    val zoom: Int,
    val row: Int,
    val col: Int,
    val subSample: Int,
    val layerIds: List,
    val opacities: List
) {
    var bitmap: ImageBitmap? = null
    var alpha: Float by mutableStateOf(0f)
}

internal data class TileSpec(val zoom: Int, val row: Int, val col: Int, val subSample: Int = 0)

internal fun Tile.sameSpecAs(
    zoom: Int,
    row: Int,
    col: Int,
    subSample: Int,
    layerIds: List,
    opacities: List
): Boolean {
    return this.zoom == zoom && this.row == row && this.col == col && this.subSample == subSample
            && this.layerIds == layerIds && this.opacities == opacities
}