iOS Metal: fix stale framebuffer on rotation (#4954)

Ports/iOSPort/nativeSources/CodenameOne_GLViewController.m

@@ -2540,7 +2540,7 @@ -(void)updateCanvas:(BOOL)animated {
     // the display width/height each time to match the view, without performing other resizing
     // details, so it is possible that the size change event still needs to be sent
     // even if the display width already matches the value we're given here.
-    [[self eaglView] updateFrameBufferSize:(int)size.width h:(int)size.height];
+    [[self eaglView] updateFrameBufferSize:(int)(size.width * scaleValue) h:(int)(size.height * scaleValue)];
     displayWidth = (int)size.width * scaleValue;
     displayHeight = (int)size.height * scaleValue;
     screenSizeChanged(displayWidth, displayHeight);
@@ -3282,9 +3282,14 @@ -(void) viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id)coor
     }
 
     // simply create a property of 'BOOL' type
-    [[self eaglView] updateFrameBufferSize:(int)size.width h:(int)size.height];
+    // Pass physical pixels: viewWillTransitionToSize: fires before UIKit
+    // updates the view's bounds, so on the Metal backend the EAGLView's
+    // bounds read would still return the previous orientation. The
+    // METALView resize logic trusts these parameters; the EAGLView
+    // implementation is a no-op (#4954).
+    [[self eaglView] updateFrameBufferSize:(int)(size.width * scaleValue) h:(int)(size.height * scaleValue)];
     [[self eaglView] deleteFramebuffer];
-    
+
     displayWidth = (int)size.width * scaleValue;
     displayHeight = (int)size.height * scaleValue;
 
@@ -3325,7 +3330,7 @@ -(void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOr
         return;
     }
 
-    [[self eaglView] updateFrameBufferSize:(int)self.view.bounds.size.width h:(int)self.view.bounds.size.height];
+    [[self eaglView] updateFrameBufferSize:(int)(self.view.bounds.size.width * scaleValue) h:(int)(self.view.bounds.size.height * scaleValue)];
     [[self eaglView] deleteFramebuffer];
 
     displayWidth = (int)self.view.bounds.size.width * scaleValue;

Ports/iOSPort/nativeSources/METALView.m

@@ -228,16 +228,28 @@ - (void)deleteFramebuffer
 
 
 -(void)updateFrameBufferSize:(int)w h:(int)h {
-    // Ignore the passed w/h -- CodenameOne_GLViewController.m calls this with
-    // logical points (self.view.bounds.size), but the Metal drawable and
-    // projection must be in physical pixels. The GL path tolerates the
-    // logical-point argument because EAGLView.updateFrameBufferSize: is a
-    // no-op (dimensions get read back from the renderbuffer after the layer
-    // is bound). For Metal we always compute from our own layer bounds.
-    CGSize sz = self.bounds.size;
-    CGFloat s = self.contentScaleFactor;
-    int pw = (int)(sz.width * s);
-    int ph = (int)(sz.height * s);
+    // Trust caller-supplied physical-pixel dimensions; fall back to bounds
+    // only if the caller passes 0. Reading self.bounds alone is unsafe
+    // during rotation: viewWillTransitionToSize: in CodenameOne_GLView-
+    // Controller fires BEFORE UIKit updates the view's bounds, so a
+    // bounds-derived size matches the cached (old) framebuffer dimensions
+    // and the early-return below would leave screenTexture, the projection
+    // matrix and stencil texture at the previous orientation. CAMetalLayer's
+    // drawableSize is auto-resized by UIKit on rotation, so the next
+    // drawFrame would blit the old-sized screenTexture into the new-sized
+    // drawable -- portrait content lands in a corner of the landscape
+    // drawable and the remaining pixels read back uninitialised, surfacing
+    // as the smeared/pink frames reported in #4954. The callers in this
+    // file (initWithCoder, layoutSubviews) and the GLViewController callers
+    // all pass physical pixels.
+    int pw = w;
+    int ph = h;
+    if (pw <= 0 || ph <= 0) {
+        CGSize sz = self.bounds.size;
+        CGFloat s = self.contentScaleFactor;
+        pw = (int)(sz.width * s);
+        ph = (int)(sz.height * s);
+    }
     if (pw <= 0 || ph <= 0) return;
     if (pw == framebufferWidth && ph == framebufferHeight) {
         return;