refactor(apple): advance artboard with layout fit on layoutSubview (#10427) 759f2fc742

Co-authored-by: David Skuza <david@rive.app>

Source/Renderer/include/RiveMetalDrawableView.h

@@ -25,6 +25,7 @@
 @property(nullable, nonatomic, readonly) id<CAMetalDrawable> currentDrawable;
 @property(nonatomic) MTLPixelFormat colorPixelFormat;
 @property(nonatomic) CGSize drawableSize;
+- (void)drawableSizeDidChange:(CGSize)drawableSize;
 @end
 
 #endif /* RiveMetalDrawableView_h */

Source/Renderer/rive_renderer_view.mm

@@ -110,6 +110,7 @@
     newSize.width *= self.traitCollection.displayScale;
     newSize.height *= self.traitCollection.displayScale;
     self.drawableSize = newSize;
+    [self drawableSizeDidChange:newSize];
 }
 
 - (void)setContentScaleFactor:(CGFloat)contentScaleFactor
@@ -145,9 +146,19 @@
     [self drawRect:self.bounds];
 }
 
+- (void)drawableSizeDidChange:(CGSize)drawableSize
+{}
+
 @end
 #else
 @implementation RiveMTKView
+- (void)setDrawableSize:(CGSize)drawableSize
+{
+    [super setDrawableSize:drawableSize];
+    [self drawableSizeDidChange:drawableSize];
+}
+- (void)drawableSizeDidChange:(CGSize)drawableSize
+{}
 @end
 #endif
 

Source/RiveView.swift

@@ -436,6 +436,28 @@ open class RiveView: RiveRendererView {
         }
     }
 
+    open override func drawableSizeDidChange(_ drawableSize: CGSize) {
+        super.drawableSizeDidChange(drawableSize)
+        if fit == .layout, let artboard = riveModel?.artboard {
+            let currentSize = drawableSize
+            let artboardSize = artboard.bounds().size
+            if currentSize != artboardSize {
+                // We can use currentSize; we are mirroring setting
+                // the updated layout size (if needed) as in drawRive,
+                // which uses the same rect as drawRect (assuming 'self')
+                let scale = layoutScaleFactor == RiveView.Constants.layoutScaleFactorAutomatic ? _layoutScaleFactor : layoutScaleFactor
+                artboard.setWidth(Double(currentSize.width) / scale)
+                artboard.setHeight(Double(currentSize.height) / scale)
+                advance(delta: 0)
+            }
+        }
+    }
+
+    open override func layoutSubviews() {
+        super.layoutSubviews()
+        drawableSizeDidChange(drawableSize)
+    }
+
     // MARK: - UITraitCollection
     #if os(iOS)
     open override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {