more interesting splash screen wip

src/net/torvald/terrarum/App.java

@@ -280,6 +280,11 @@ public class App implements ApplicationListener {
     private static TerrarumGamescreen currentScreen;
     private static LoadScreenBase currentSetLoadScreen;
 
+    /** When set, App.render() will capture postProcessorOutFBO and then transition to this screen after the current frame finishes. */
+    public static TerrarumGamescreen pendingScreenWithCapture = null;
+    /** Populated by the deferred-capture path; consumed by TitleScreen.show(). */
+    public static Pixmap captureLastFrame = null;
+
     private void initViewPort(int width, int height) {
         // Set Y to point downwards
         camera.setToOrtho(true, width, height); // some elements are pre-flipped, while some are not. The statement itself is absolutely necessary to make edge of the screen as the origin
@@ -767,6 +772,17 @@ public class App implements ApplicationListener {
 
             currentScreen.render(UPDATE_RATE);
             postProcessorOutFBO = TerrarumPostProcessor.INSTANCE.draw(Gdx.graphics.getDeltaTime(), camera.combined, renderFBO);
+
+            // Deferred transition: capture the just-rendered frame then switch screens.
+            // This fires AFTER the current screen has fully rendered so the capture is of the real last ingame frame.
+            if (pendingScreenWithCapture != null) {
+                TerrarumGamescreen next = pendingScreenWithCapture;
+                pendingScreenWithCapture = null;
+                FrameBufferManager.begin(postProcessorOutFBO);
+                captureLastFrame = Pixmap.createFromFrameBuffer(0, 0, postProcessorOutFBO.getWidth(), postProcessorOutFBO.getHeight());
+                FrameBufferManager.end();
+                setScreen(next);
+            }
         }
 
 
@@ -930,6 +946,9 @@ public class App implements ApplicationListener {
 
         logoBatch.end();
 
+        // draw loading bar and subtitle
+        SplashScreen.render(logoBatch, camera);
+
         // draw health messages
         if (getConfigBoolean("showhealthmessageonstartup")) {
             logoBatch.setShader(null);

src/net/torvald/terrarum/CommonResourcePool.kt

@@ -31,6 +31,16 @@ object CommonResourcePool {
 
     private val slowLoadingQueue = ConcurrentLinkedQueue<ResourceLoadingDescriptor>()
     private val slowLoadingRemaining = AtomicInteger(0)
+    private val slowLoadingTotal = AtomicInteger(0)
+
+    /** 0.0 = not started yet, 1.0 = all done. Only meaningful during / after [loadAllSlowly]. */
+    val loadingProgress: Float
+        get() {
+            val total = slowLoadingTotal.get()
+            if (total == 0) return 0f
+            val remaining = slowLoadingRemaining.get()
+            return (total - remaining).toFloat() / total.toFloat()
+        }
 
     fun setGLThread(thread: Thread) {
         glThread = thread
@@ -152,6 +162,7 @@ object CommonResourcePool {
             val desc = loadingList.removeFirst()
             slowLoadingQueue.add(desc)
             slowLoadingRemaining.incrementAndGet()
+            slowLoadingTotal.incrementAndGet()
         }
         // Block until the GL thread has processed all slow items
         while (slowLoadingRemaining.get() > 0) {

src/net/torvald/terrarum/SplashScreen.kt

@@ -0,0 +1,63 @@
+package net.torvald.terrarum
+
+import com.badlogic.gdx.graphics.Color
+import com.badlogic.gdx.graphics.OrthographicCamera
+import com.badlogic.gdx.graphics.g2d.SpriteBatch
+import net.torvald.terrarum.ui.Toolkit
+import net.torvald.terrarum.ui.UICanvas
+import net.torvald.terrarum.ui.UIItemHorzSlider
+
+/**
+ * Draws the loading bar and subtitle on the cold-boot splash screen.
+ * Called from App.drawSplash() (Java static context) on the GL thread.
+ *
+ * Created by minjaesong on 2026-04-06.
+ */
+object SplashScreen {
+
+    private val stubParent = object : UICanvas() {
+        override var width = 0
+        override var height = 0
+        override fun updateImpl(delta: Float) {}
+        override fun renderImpl(frameDelta: Float, batch: SpriteBatch, camera: OrthographicCamera) {}
+        override fun dispose() {}
+    }
+
+    private var loadingBar: UIItemHorzSlider? = null
+    private var lastBarWidth = 0
+
+    private val subtitleCol = Color(0.75f, 0.75f, 0.75f, 1f)
+
+    @JvmStatic
+    fun render(batch: SpriteBatch, camera: OrthographicCamera) {
+        val progress = CommonResourcePool.loadingProgress
+        val barWidth = (Toolkit.drawWidth * 0.4f).toInt().coerceAtLeast(200)
+        val barX = (Toolkit.drawWidth - barWidth) / 2
+        val barY = App.scr.height - 48
+
+        if (loadingBar == null || lastBarWidth != barWidth) {
+            lastBarWidth = barWidth
+            loadingBar = UIItemHorzSlider(stubParent, barX, barY, 0.0, 0.0, 1.0, barWidth).also {
+                it.suppressHaptic = true
+                it.isEnabled = false
+            }
+        }
+
+        val bar = loadingBar ?: return
+        bar.posX = barX
+        bar.posY = barY
+        bar.handleWidth = (progress * barWidth).toInt().coerceIn(12, barWidth)
+
+        val subtitle = "${App.GAME_NAME}  ${App.getVERSION_STRING()}"
+        val subtitleW = App.fontGame.getWidth(subtitle)
+        val subtitleX = (Toolkit.drawWidth - subtitleW) / 2f
+        val subtitleY = (barY - 20).toFloat() // leave gap above the bar
+
+        batch.begin()
+        batch.color = subtitleCol
+        App.fontGame.draw(batch, subtitle, subtitleX, subtitleY)
+        batch.color = Color.WHITE
+        bar.render(0f, batch, camera)
+        batch.end()
+    }
+}

src/net/torvald/terrarum/modulebasegame/BuildingMaker.kt

@@ -727,7 +727,7 @@ class MovableWorldCamera(val parent: BuildingMaker) : ActorHumanoid(0, physProp
 
 class YamlCommandExit : YamlInvokable {
     override fun invoke(args: Array<Any>) {
-        App.setScreen(TitleScreen(App.batch))
+        App.pendingScreenWithCapture = TitleScreen(App.batch)
     }
 }
 

src/net/torvald/terrarum/modulebasegame/TitleScreen.kt

@@ -75,6 +75,7 @@ class TitleScreen(batch: FlippingSpriteBatch) : IngameInstance(batch) {
     private var splashCapture: Texture? = null
     private var settleFrames = 0
     private var transitionState = 0 // 0=loading, 1=settling, 2=fading, 3=done
+    private var enteringFromIngame = false
 
     private lateinit var demoWorld: GameWorld
     private lateinit var cameraNodes: FloatArray // camera Y-pos
@@ -296,6 +297,15 @@ class TitleScreen(batch: FlippingSpriteBatch) : IngameInstance(batch) {
     override fun show() {
         printdbg(this, "show() called")
 
+        // consume the pre-captured frame provided by App.render()'s deferred-capture path
+        val pixmap = App.captureLastFrame
+        App.captureLastFrame = null
+        if (pixmap != null) {
+            splashCapture = Texture(pixmap)
+            pixmap.dispose()
+            enteringFromIngame = true
+        }
+
         for (k in Input.Keys.F1..Input.Keys.F12) {
             KeyToggler.forceSet(k, false)
         }
@@ -325,15 +335,22 @@ class TitleScreen(batch: FlippingSpriteBatch) : IngameInstance(batch) {
 
     override fun renderImpl(updateRate: Float) {
         when (transitionState) {
-            // Loading phase: show splash, advance GL load steps
+            // Loading phase: show splash or last ingame frame, advance GL load steps
             0 -> {
-                App.drawSplash()
+                if (enteringFromIngame) {
+                    // hold the last ingame frame while the title screen loads in the background
+                    drawSplashCapture(1f)
+                } else {
+                    App.drawSplash()
+                }
                 processGLLoadStep()
                 if (loadDone) {
-                    // capture the current framebuffer (splash) as a texture
-                    val pixmap = Pixmap.createFromFrameBuffer(0, 0, App.scr.width, App.scr.height)
-                    splashCapture = Texture(pixmap)
-                    pixmap.dispose()
+                    if (!enteringFromIngame) {
+                        // capture the current splash screen frame for the crossfade
+                        val pixmap = Pixmap.createFromFrameBuffer(0, 0, App.scr.width, App.scr.height)
+                        splashCapture = Texture(pixmap)
+                        pixmap.dispose()
+                    }
                     transitionState = 1
                     settleFrames = 0
                 }

src/net/torvald/terrarum/modulebasegame/ui/UIInventoryEscMenu.kt

@@ -176,7 +176,7 @@ class UIInventoryEscMenu(val full: UIInventoryFull) : UICanvas() {
             when (new) {
                 2 -> {
                     areYouSureMainMenuButtons.deselect()
-                    App.setScreen(TitleScreen(App.batch))
+                    App.pendingScreenWithCapture = TitleScreen(App.batch)
                 }
                 3 -> {
                     screen = 0; areYouSureMainMenuButtons.deselect()

src/net/torvald/terrarum/ui/UIItemHorzSlider.kt

@@ -63,7 +63,7 @@ class UIItemHorzSlider(
     override fun update(delta: Float) {
         super.update(delta)
 
-        mouseOnHandle = itemRelativeMouseX in handlePos.roundToInt() until handlePos.roundToInt() + handleWidth && itemRelativeMouseY in 0 until height
+        mouseOnHandle = if (!isEnabled) false else itemRelativeMouseX in handlePos.roundToInt() until handlePos.roundToInt() + handleWidth && itemRelativeMouseY in 0 until height
 
         // update handle position and value
         if (mouseUp && Terrarum.mouseDown || mouseLatched) {

src/net/torvald/terrarum/ui/UIItemVertSlider.kt

@@ -60,7 +60,7 @@ class UIItemVertSlider(
     override fun update(delta: Float) {
         super.update(delta)
 
-        mouseOnHandle = itemRelativeMouseY in handlePos.roundToInt() until handlePos.roundToInt() + handleHeight && itemRelativeMouseX in 0 until width
+        mouseOnHandle = if (!isEnabled) false else itemRelativeMouseY in handlePos.roundToInt() until handlePos.roundToInt() + handleHeight && itemRelativeMouseX in 0 until width
 
         // update handle position and value
         if (mouseUp && Terrarum.mouseDown || mouseLatched) {