From c66eebc2c23a8b41eb618c715296c2a7dd135f43 Mon Sep 17 00:00:00 2001
From: Ivan Matkov <ivan.matkov@jetbrains.com>
Date: Tue, 28 May 2024 19:39:01 +0200
Subject: [PATCH] Redraw immediately on panel size change (#923)

Fixes a couple of issues like:
https://github.com/JetBrains/compose-multiplatform/issues/4744 (TODO:
collect all references)

Before (slow-mo)


https://github.com/JetBrains/skiko/assets/1836384/5768b139-d08f-4142-8c14-2969107807f9



After (slow-mo)


https://github.com/JetBrains/skiko/assets/1836384/cc9a5103-3d30-412e-a5a4-baf590d657b8
---
 .../org/jetbrains/skiko/SkiaLayer.awt.kt      | 27 +++++++++++++++----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/skiko/src/awtMain/kotlin/org/jetbrains/skiko/SkiaLayer.awt.kt b/skiko/src/awtMain/kotlin/org/jetbrains/skiko/SkiaLayer.awt.kt
index 8720ee486..80bbf59ea 100644
--- a/skiko/src/awtMain/kotlin/org/jetbrains/skiko/SkiaLayer.awt.kt
+++ b/skiko/src/awtMain/kotlin/org/jetbrains/skiko/SkiaLayer.awt.kt
@@ -229,8 +229,6 @@ actual open class SkiaLayer internal constructor(
         jComponent.add(this)
     }
 
-    private var keyEvent: KeyEvent? = null
-
     val clipComponents = mutableListOf<ClipRectangle>()
 
     @Volatile
@@ -312,13 +310,32 @@ actual open class SkiaLayer internal constructor(
     override fun paint(g: java.awt.Graphics) {
         Logger.debug { "Paint called on: $this" }
         checkContentScale()
+        tryRedrawImmediately()
+    }
+
+    override fun setBounds(x: Int, y: Int, width: Int, height: Int) {
+        super.setBounds(x, y, width, height)
+
+        // To avoid visual artifacts on Windows/Direct3D,
+        // redrawing should be performed immediately, without scheduling to "later".
+        // Subscribing to events instead of overriding this method won't help too.
+        //
+        // Please note that calling redraw during layout might break software renderers,
+        // so applying this fix only for Direct3D case.
+        if (renderApi == GraphicsApi.DIRECT3D) {
+            redrawer?.syncSize()
+            tryRedrawImmediately()
+        }
+    }
 
-        // `paint` can be called when we already inside `draw` method.
+    private fun tryRedrawImmediately() {
+        if (!isShowing) return
+
+        // It might be called inside `renderDelegate`,
+        // so to avoid recursive call (not supported) just schedule redrawing.
         //
         // For example if we call some AWT function inside renderer.onRender,
         // such as `jframe.isEnabled = false` on Linux
-        //
-        // To avoid recursive call of `draw` (we don't support recursive calls) we just schedule redrawing.
         if (isRendering) {
             redrawer?.needRedraw()
         } else {