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package com.mapbox.mapboxsdk.maps.widgets.scaleview;
import android.graphics.PointF;
import com.mapbox.mapboxsdk.camera.CameraPosition;
import com.mapbox.mapboxsdk.geometry.LatLng;
import com.mapbox.mapboxsdk.maps.Projection;
class MapScaleModel {
private final int[] meters = {
150,350,700, 1500, 2500, 5000, 10000, 20000, 40000, 100000, 150000, 350000, 700000, 1500000, 2500000};
private final LatLng src = new LatLng(31, 121);
private int maxWidth;
private double zoom = -1;
private Scale scale;
MapScaleModel() {
}
void setMaxWidth(int width) {
maxWidth = width;
}
Scale setProjection(Projection projection, CameraPosition cameraPosition) {
if (zoom == cameraPosition.zoom) return scale;
int distance = 0;
int distanceIndex = meters.length;
double screenDistance = maxWidth + 1;
while (screenDistance > maxWidth && distanceIndex > 0) {
distance = meters[--distanceIndex];
LatLng dest = DistanceUtils.translatePoint(src, distance, 120);
PointF pointSrc = projection.toScreenLocation(src);
PointF pointDest = projection.toScreenLocation(dest);
screenDistance = Math.sqrt(Math.pow(pointSrc.x - pointDest.x, 2) + Math.pow(pointSrc.y - pointDest.y, 2));
}
zoom = cameraPosition.zoom;
scale = new Scale(text(distance), (float) screenDistance);
return scale;
}
private String text(int distance) {
if (distance < 1000) return distance + " m";
else return distance / 1000 + " km";
}
}
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