From d9d74c9a6b6211223230a623cd97e4755f8f60bd Mon Sep 17 00:00:00 2001
From: Tobias Zwick <newton@westnordost.de>
Date: Thu, 17 Aug 2023 14:14:40 +0200
Subject: [PATCH] set and enforce a maximum tilt (fixes #5177)

---
 .../screens/main/map/tangram/CameraManager.kt |  8 ++++++--
 .../main/map/tangram/KtMapController.kt       | 20 ++++++++++++++++++-
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/app/src/main/java/de/westnordost/streetcomplete/screens/main/map/tangram/CameraManager.kt b/app/src/main/java/de/westnordost/streetcomplete/screens/main/map/tangram/CameraManager.kt
index 99468c0c31..0f9a0d3617 100644
--- a/app/src/main/java/de/westnordost/streetcomplete/screens/main/map/tangram/CameraManager.kt
+++ b/app/src/main/java/de/westnordost/streetcomplete/screens/main/map/tangram/CameraManager.kt
@@ -21,6 +21,7 @@ import de.westnordost.streetcomplete.data.osm.mapdata.LatLon
 import de.westnordost.streetcomplete.util.ktx.nowAsEpochMilliseconds
 import de.westnordost.streetcomplete.util.ktx.runImmediate
 import kotlin.math.PI
+import kotlin.math.min
 
 /**
  *  Controls the camera of a Tangram MapController. Use in place of the
@@ -68,6 +69,8 @@ class CameraManager(private val c: MapController, private val contentResolver: C
 
     val isAnimating: Boolean get() = lastAnimator != null
 
+    var maximumTilt: Float = PI.toFloat() / 8f // 45°
+
     interface AnimationsListener {
         @UiThread fun onAnimationsStarted()
         @UiThread fun onAnimating()
@@ -115,7 +118,7 @@ class CameraManager(private val c: MapController, private val contentResolver: C
             _tangramCamera.longitude = it.longitude
         }
         update.rotation?.let { _tangramCamera.rotation = it }
-        update.tilt?.let { _tangramCamera.tilt = it }
+        update.tilt?.let { _tangramCamera.tilt = min(it, maximumTilt) }
         update.zoom?.let { _tangramCamera.zoom = it }
         pushCameraPositionToController()
     }
@@ -133,7 +136,8 @@ class CameraManager(private val c: MapController, private val contentResolver: C
             assignAnimation("rotation", animator)
         }
         update.tilt?.let {
-            propValues.add(PropertyValuesHolder.ofFloat(TangramTiltProperty, it))
+            val tilt = min(it, maximumTilt)
+            propValues.add(PropertyValuesHolder.ofFloat(TangramTiltProperty, tilt))
             assignAnimation("tilt", animator)
         }
         update.zoom?.let {
diff --git a/app/src/main/java/de/westnordost/streetcomplete/screens/main/map/tangram/KtMapController.kt b/app/src/main/java/de/westnordost/streetcomplete/screens/main/map/tangram/KtMapController.kt
index 4e8211e7b8..90cc13e0f0 100644
--- a/app/src/main/java/de/westnordost/streetcomplete/screens/main/map/tangram/KtMapController.kt
+++ b/app/src/main/java/de/westnordost/streetcomplete/screens/main/map/tangram/KtMapController.kt
@@ -40,6 +40,7 @@ import java.util.concurrent.ConcurrentLinkedQueue
 import kotlin.coroutines.Continuation
 import kotlin.coroutines.resume
 import kotlin.coroutines.resumeWithException
+import kotlin.math.PI
 import kotlin.math.log10
 import kotlin.math.max
 import kotlin.math.min
@@ -207,6 +208,12 @@ class KtMapController(private val c: MapController, contentResolver: ContentReso
         set(value) { c.maximumZoomLevel = value }
         get() = c.maximumZoomLevel
 
+    var maximumTilt: Float
+        set(value) {
+            cameraManager.maximumTilt = value
+        }
+        get() = cameraManager.maximumTilt
+
     fun screenPositionToLatLon(screenPosition: PointF): LatLon? = c.screenPositionToLngLat(screenPosition)?.toLatLon()
     fun latLonToScreenPosition(latLon: LatLon): PointF = c.lngLatToScreenPosition(latLon.toLngLat())
     fun latLonToScreenPosition(latLon: LatLon, screenPositionOut: PointF, clipToViewport: Boolean) =
@@ -329,7 +336,18 @@ class KtMapController(private val c: MapController, contentResolver: ContentReso
 
     /* -------------------------------------- Touch input --------------------------------------- */
 
-    fun setShoveResponder(responder: TouchInput.ShoveResponder?) { gestureManager.setShoveResponder(responder) }
+    fun setShoveResponder(responder: TouchInput.ShoveResponder?) {
+        // enforce maximum tilt
+        gestureManager.setShoveResponder(object : TouchInput.ShoveResponder {
+            override fun onShoveBegin() = responder?.onShoveBegin() ?: false
+            override fun onShoveEnd() = responder?.onShoveEnd() ?: false
+
+            override fun onShove(distance: Float): Boolean {
+                if (cameraPosition.tilt >= maximumTilt && distance < 0) return true
+                return responder?.onShove(distance) ?: false
+            }
+        })
+    }
     fun setScaleResponder(responder: TouchInput.ScaleResponder?) { gestureManager.setScaleResponder(responder) }
     fun setRotateResponder(responder: TouchInput.RotateResponder?) { gestureManager.setRotateResponder(responder) }
     fun setPanResponder(responder: TouchInput.PanResponder?) { gestureManager.setPanResponder(responder) }