fix(flip): seperate flip calls

packages/core/src/RenderingEngine/Viewport.ts

@@ -1873,8 +1873,11 @@ class Viewport {
     // right now if the view presentation requires a flip, it will flicker. The
     // correct way to handle this is to wait for camera and flip together and then
     // do one render
-    if (flipHorizontal || flipVertical) {
-      this.flip({ flipHorizontal, flipVertical });
+    if (flipHorizontal !== undefined) {
+      this.flip({ flipHorizontal });
+    }
+    if (flipVertical !== undefined) {
+      this.flip({ flipVertical });
     }
   }
 

tests/stackAPI.spec.ts

@@ -86,4 +86,16 @@ test.describe('Stack Viewport API', async () => {
       screenShotPaths.stackAPI.resetViewport
     );
   });
+
+  test('should flip both h and v and be able to scroll and keep the flip', async ({
+    page,
+  }) => {
+    await page.getByRole('button', { name: 'Flip H' }).click();
+    await page.getByRole('button', { name: 'Flip V' }).click();
+
+    // click on next image
+    await page.getByRole('button', { name: 'Next Image' }).click();
+    const locator = page.locator('.cornerstone-canvas');
+    await checkForScreenshot(page, locator, screenShotPaths.stackAPI.flipBoth);
+  });
 });

tests/utils/screenShotPaths.ts

@@ -15,6 +15,7 @@ const screenShotPaths = {
     viewport: 'viewport.png',
   },
   stackAPI: {
+    flipBoth: 'flipBoth.png',
     setVoiRange: 'setVoiRange.png',
     nextImage: 'nextImage.png',
     previousImage: 'previousImage.png',