Fix iOS Metal foreground framebuffer reset

.github/workflows/purchase-e2e.yml

@@ -272,6 +272,20 @@ jobs:
           echo 'KERNEL=="kvm", GROUP="kvm", MODE="0666", OPTIONS+="static_node=kvm"' | sudo tee /etc/udev/rules.d/99-kvm4all.rules
           sudo udevadm control --reload-rules
           sudo udevadm trigger --name-match=kvm
+      - name: Preinstall Android emulator package
+        run: |
+          set -euo pipefail
+          printf 'y\n%.0s' {1..100} | sdkmanager --licenses >/dev/null || true
+          for attempt in 1 2 3; do
+            if sdkmanager --install emulator --channel=0; then
+              exit 0
+            fi
+            echo "Android emulator package install failed on attempt ${attempt}; retrying"
+            rm -rf "${ANDROID_SDK_ROOT:-/usr/local/lib/android/sdk}/.temp" || true
+            sleep 10
+          done
+          echo "::error::Unable to install Android emulator package after retries"
+          exit 1
       - name: Run Android purchase instrumentation test (targeted)
         uses: reactivecircus/android-emulator-runner@v2
         with:

Ports/iOSPort/nativeSources/CN1RenderingView.h

@@ -48,6 +48,9 @@
 - (void)keyboardDoneClicked;
 - (void)keyboardNextClicked;
 - (void)textFieldDidChange;
+@optional
+- (void)invalidateRetainedFramebuffer;
+- (void)prepareRetainedFramebufferForDrawRect:(CGRect)rect displayWidth:(int)displayWidth displayHeight:(int)displayHeight;
 @end
 
 #endif

Ports/iOSPort/nativeSources/CodenameOne_GLAppDelegate.m

@@ -43,6 +43,7 @@
 #endif
 
 extern BOOL isIOS10();
+extern void repaintUI();
 int pendingRemoteNotificationRegistrations = 0;
 
 BOOL isAppSuspended = NO;
@@ -290,6 +291,12 @@ - (void)cn1ApplicationWillEnterForeground
     com_codename1_impl_ios_IOSImplementation_applicationWillEnterForeground__(CN1_THREAD_GET_STATE_PASS_SINGLE_ARG);
     CodenameOne_GLViewController* vc = [CodenameOne_GLViewController instance];
     if (vc != nil) {
+#ifdef CN1_USE_METAL
+        id renderingView = [vc eaglView];
+        if ([renderingView respondsToSelector:@selector(invalidateRetainedFramebuffer)]) {
+            [renderingView invalidateRetainedFramebuffer];
+        }
+#endif
         // Defer to the next runloop so UIKit can settle the view bounds
         // after the snapshot rotation. updateCanvas itself also
         // orientation-validates the bounds for an extra safety net under

Ports/iOSPort/nativeSources/CodenameOne_GLViewController.m

@@ -4299,7 +4299,22 @@ - (void)drawFrame:(CGRect)rect allowInactive:(BOOL)allowInactive
         return;
     }
 #endif
-    [[self eaglView] setFramebuffer];
+    id renderingView = [self eaglView];
+#ifdef CN1_USE_METAL
+    BOOL hasScreenOps = NO;
+    if (currentTarget != nil) {
+        for (ExecutableOp *ex in currentTarget) {
+            if ([ex target] == nil) {
+                hasScreenOps = YES;
+                break;
+            }
+        }
+    }
+    if (hasScreenOps && [renderingView respondsToSelector:@selector(prepareRetainedFramebufferForDrawRect:displayWidth:displayHeight:)]) {
+        [renderingView prepareRetainedFramebufferForDrawRect:rect displayWidth:displayWidth displayHeight:displayHeight];
+    }
+#endif
+    [renderingView setFramebuffer];
     GLErrorLog;
     BOOL drewContentOps = NO;
     if(currentTarget != nil) {
@@ -4446,7 +4461,7 @@ - (void)drawFrame:(CGRect)rect allowInactive:(BOOL)allowInactive
     }
     GLErrorLog;
 
-    [[self eaglView] presentFramebuffer];
+    [renderingView presentFramebuffer];
     GLErrorLog;
     if (drewContentOps && !cn1LaunchPlaceholderDone) {
         // First frame with real content is on screen -- fade out the launch

Ports/iOSPort/nativeSources/METALView.h

@@ -50,6 +50,13 @@
     // turn or by the next normal presentFramebuffer -- whichever lands first.
     // Read/written on the main thread only, so no synchronisation is needed.
     BOOL needsResizePresent;
+
+    // The persistent screenTexture is private GPU storage. iOS may discard or
+    // leave it stale across app suspension, and CN1 can resume with only
+    // partial dirty-region flushes. Mark it invalid on foreground; the first
+    // full-screen repaint clears it before drawing fresh content.
+    BOOL retainedFramebufferInvalid;
+    BOOL clearRetainedFramebufferOnNextFrame;
 }
 @property (nonatomic, retain) id<MTLCommandQueue> commandQueue;
 @property (nonatomic, retain) id<MTLCommandBuffer> commandBuffer;
@@ -82,9 +89,11 @@
 - (BOOL)presentFramebuffer;
 -(void)presentPreservedFrameIfNeeded;
 -(void)updateFrameBufferSize:(int)w h:(int)h;
+-(void)invalidateRetainedFramebuffer;
+-(void)prepareRetainedFramebufferForDrawRect:(CGRect)rect displayWidth:(int)displayWidth displayHeight:(int)displayHeight;
 -(void)textFieldDidChange;
 -(void) keyboardDoneClicked;
 -(void) keyboardNextClicked;
 -(void) addPeerComponent:(UIView*) view;
 @end
-#endif
+#endif

Ports/iOSPort/nativeSources/METALView.m

@@ -519,6 +519,36 @@ -(void)presentPreservedFrameIfNeeded {
     [presentCb commit];
 }
 
+-(void)invalidateRetainedFramebuffer {
+    retainedFramebufferInvalid = YES;
+    clearRetainedFramebufferOnNextFrame = NO;
+    // A preserved resize frame is also stale after a suspend/resume cycle.
+    needsResizePresent = NO;
+}
+
+-(void)prepareRetainedFramebufferForDrawRect:(CGRect)rect displayWidth:(int)displayWidth displayHeight:(int)displayHeight {
+    if (!retainedFramebufferInvalid) {
+        return;
+    }
+    // During rotation, displayWidth/displayHeight can briefly lag the Metal
+    // drawable. Only consume the invalidation when the repaint covers the
+    // actual retained framebuffer we are about to load from.
+    int targetWidth = framebufferWidth > 0 ? framebufferWidth : displayWidth;
+    int targetHeight = framebufferHeight > 0 ? framebufferHeight : displayHeight;
+    if (targetWidth <= 0 || targetHeight <= 0) {
+        return;
+    }
+    CGFloat minX = rect.origin.x;
+    CGFloat minY = rect.origin.y;
+    CGFloat maxX = rect.origin.x + rect.size.width;
+    CGFloat maxY = rect.origin.y + rect.size.height;
+    if (minX <= 0.0f && minY <= 0.0f &&
+        maxX >= (CGFloat)targetWidth && maxY >= (CGFloat)targetHeight) {
+        clearRetainedFramebufferOnNextFrame = YES;
+        retainedFramebufferInvalid = NO;
+    }
+}
+
 -(void)createRenderPassDescriptor {
     if (self.screenTexture == nil) {
         self.renderPassDescriptor = nil;
@@ -532,7 +562,13 @@ -(void)createRenderPassDescriptor {
     // which would wipe everything each frame) — CN1 only queues diff ops
     // per frame; the OpenGL path relies on its renderbuffer persisting.
     colorAttachment.texture = self.screenTexture;
-    colorAttachment.loadAction = MTLLoadActionLoad;
+    if (clearRetainedFramebufferOnNextFrame) {
+        colorAttachment.loadAction = MTLLoadActionClear;
+        colorAttachment.clearColor = MTLClearColorMake(0.0, 0.0, 0.0, 1.0);
+        clearRetainedFramebufferOnNextFrame = NO;
+    } else {
+        colorAttachment.loadAction = MTLLoadActionLoad;
+    }
     colorAttachment.storeAction = MTLStoreActionStore;
     // Attach the Stencil8 texture for polygon-shape clipping (#3921).
     // Cleared at the start of every frame and discarded at the end --
@@ -775,4 +811,4 @@ -(void)layoutSubviews
 
 
 @end
-#endif
+#endif