chore(upstream): v4.4.7 low-risk backports — night overlay alloc-free, radar inset padding, sunrise/sunset tests

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atsunatsu committed 2026-09-14 13:41:15 +08:00
1 parent d8d3d81648
commit 2773145e0c
3 files changed
+104 -14

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@@ -21,6 +21,7 @@ import android.graphics.Canvas
import android.graphics.Color
import android.graphics.Paint
import android.graphics.RectF
import org.osmdroid.util.GeoPoint
import org.osmdroid.views.MapView
import org.osmdroid.views.overlay.Overlay
import kotlin.math.cos
@@ -39,9 +40,11 @@ import kotlin.math.sin
* exceeds 90°, i.e. the dot product of the two unit vectors is negative:
* dot = sin(lat)*sin(sunLat) + cos(lat)*cos(sunLat)*cos(lon - sunLon) < 0
*
* Performance: we sample one column per [stepPx] pixels (default 4) and draw
* Performance: we sample one column per stepPx pixels (default 4) and draw
* filled vertical rectangles. On a 1080-wide screen this means ~270 trig
* evaluations per row, which is imperceptible.
* evaluations per row, which is imperceptible. draw() is called on every
* frame, so it must stay allocation-free — all fromPixels() calls reuse a
* single GeoPoint instance.
*/
class MapNightOverlay : Overlay() {
@@ -58,6 +61,9 @@ class MapNightOverlay : Overlay() {
private val rect = RectF()
/** Reused across every fromPixels() call — draw() runs on every frame, so it must not allocate */
private val reusableGeoPoint = GeoPoint(0.0, 0.0)
override fun draw(canvas: Canvas, mapView: MapView, shadow: Boolean) {
if (shadow) return
@@ -71,6 +77,15 @@ class MapNightOverlay : Overlay() {
val h = mapView.height
val stepPx = 4 // sample every N pixels — balance quality vs CPU
// The map is never rotated, so latitude depends only on y and longitude only on x.
// Resolve the top/bottom latitudes once instead of once per column.
val latTopRad = Math.toRadians((proj.fromPixels(0, 0, reusableGeoPoint) ?: return).latitude)
val latBotRad = Math.toRadians((proj.fromPixels(0, h - 1, reusableGeoPoint) ?: return).latitude)
val sinLatTop = sin(latTopRad)
val cosLatTop = cos(latTopRad)
val sinLatBot = sin(latBotRad)
val cosLatBot = cos(latBotRad)
// We scan column by column. For each column we determine the longitude,
// then find the latitude range that is in night and shade it.
// Since longitude is constant along a vertical strip and the day/night
@@ -79,22 +94,14 @@ class MapNightOverlay : Overlay() {
var x = 0
while (x < w) {
// Get the geographic coordinate at the top and bottom of this column.
val geoTop = proj.fromPixels(x, 0) ?: run { x += stepPx; continue }
val geoBot = proj.fromPixels(x, h - 1) ?: run { x += stepPx; continue }
val geoTop = proj.fromPixels(x, 0, reusableGeoPoint) ?: run { x += stepPx; continue }
val lonRad = Math.toRadians(geoTop.longitude)
val cosLonDiff = cos(lonRad - sunLonRad)
// Top pixel geographic lat
val latTopRad = Math.toRadians(geoTop.latitude)
// Bottom pixel geographic lat (osmdroid: y=0 is top of screen, higher y = lower lat)
val latBotRad = Math.toRadians(geoBot.latitude)
// dot(sunVec, pointVec) < 0 → night
// dot = sin(lat)*sinSunLat + cos(lat)*cosSunLat*cosLonDiff
val dotTop = sin(latTopRad) * sinSunLat + cos(latTopRad) * cosSunLat * cosLonDiff
val dotBot = sin(latBotRad) * sinSunLat + cos(latBotRad) * cosSunLat * cosLonDiff
val dotTop = sinLatTop * sinSunLat + cosLatTop * cosSunLat * cosLonDiff
val dotBot = sinLatBot * sinSunLat + cosLatBot * cosSunLat * cosLonDiff
when {
dotTop < 0 && dotBot < 0 -> {
@@ -142,7 +149,7 @@ class MapNightOverlay : Overlay() {
var hi = yBot
while (hi - lo > 1) {
val mid = (lo + hi) / 2
val geo = proj.fromPixels(x, mid) ?: return mid
val geo = proj.fromPixels(x, mid, reusableGeoPoint) ?: return mid
val latRad = Math.toRadians(geo.latitude)
val dot = sin(latRad) * sinSunLat + cos(latRad) * cosSunLat * cosLonDiff
if (dot < 0) hi = mid else lo = mid