From 259b388214d1886e52a47028b358488c79f63cb3 Mon Sep 17 00:00:00 2001
From: SomeTroglodyte <63000004+SomeTroglodyte@users.noreply.github.com>
Date: Sun, 28 Jan 2024 10:10:59 +0100
Subject: [PATCH] World screen resize delayed (#11015)

* Coalesce repeated WorldScreen resize events to avoid multiple concurrent loadGame coroutines

* Remove resize instrumentation
---
 .../ui/screens/worldscreen/WorldScreen.kt     | 20 +++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/core/src/com/unciv/ui/screens/worldscreen/WorldScreen.kt b/core/src/com/unciv/ui/screens/worldscreen/WorldScreen.kt
index 8678135900..58248d9ea8 100644
--- a/core/src/com/unciv/ui/screens/worldscreen/WorldScreen.kt
+++ b/core/src/com/unciv/ui/screens/worldscreen/WorldScreen.kt
@@ -69,6 +69,8 @@ import com.unciv.utils.launchOnThreadPool
 import com.unciv.utils.withGLContext
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.coroutineScope
+import java.util.Timer
+import kotlin.concurrent.timer
 
 /**
  * Do not create this screen without seriously thinking about the implications: this is the single most memory-intensive class in the application.
@@ -216,6 +218,7 @@ class WorldScreen(
     }
 
     override fun dispose() {
+        resizeDeferTimer?.cancel()
         events.stopReceiving()
         statusButtons.dispose()
         super.dispose()
@@ -715,17 +718,23 @@ class WorldScreen(
         }
     }
 
+
+    private var resizeDeferTimer: Timer? = null
+
     override fun resize(width: Int, height: Int) {
-        if (stage.viewport.screenWidth != width || stage.viewport.screenHeight != height) {
+        resizeDeferTimer?.cancel()
+        if (resizeDeferTimer == null && stage.viewport.screenWidth == width && stage.viewport.screenHeight == height) return
+        resizeDeferTimer = timer("Resize", daemon = true, 500L, Long.MAX_VALUE) {
+            resizeDeferTimer?.cancel()
+            resizeDeferTimer = null
             startNewScreenJob(gameInfo, true) // start over
         }
     }
 
-
     override fun render(delta: Float) {
         //  This is so that updates happen in the MAIN THREAD, where there is a GL Context,
         //    otherwise images will not load properly!
-        if (shouldUpdate) {
+        if (shouldUpdate && resizeDeferTimer == null) {
             shouldUpdate = false
 
             // Since updating the worldscreen can take a long time, *especially* the first time, we disable input processing to avoid ANRs
@@ -735,12 +744,11 @@ class WorldScreen(
             if (Gdx.input.inputProcessor == null) // Update may have replaced the worldscreen with a GreatPersonPickerScreen etc, so the input would already be set
                 Gdx.input.inputProcessor = stage
         }
-//        topBar.selectedCivLabel.setText(Gdx.graphics.framesPerSecond) // for framerate testing
-
 
         super.render(delta)
     }
 
+
     private fun showTutorialsOnNextTurn() {
         if (!game.settings.showTutorials) return
         displayTutorial(TutorialTrigger.SlowStart)
@@ -799,7 +807,7 @@ class WorldScreen(
 }
 
 /** This exists so that no reference to the current world screen remains, so the old world screen can get garbage collected during [UncivGame.loadGame]. */
-private fun startNewScreenJob(gameInfo: GameInfo, autosaveDisabled:Boolean = false) {
+private fun startNewScreenJob(gameInfo: GameInfo, autosaveDisabled: Boolean = false) {
     Concurrency.run {
         val newWorldScreen = try {
             UncivGame.Current.loadGame(gameInfo)