pinch to zoom

static/gallery.css

@@ -40,7 +40,7 @@
     font-size: 24px;
     color: #fff;
     cursor: pointer;
-    z-index: 10;
+    z-index: 100;
     background: transparent;
     border: none;
     padding: 0;

static/gallery.js

@@ -1,3 +1,9 @@
+let isPinching = false;
+let pinchZoomOccurred = false;
+let initialPinchDistance = null;
+let initialScale = 1;
+let currentScale = 1;
+
 // Assume that currentGalleryImages is already declared in app.js.
 // Only declare currentGalleryIndex if it isn't defined already.
 if (typeof currentGalleryIndex === "undefined") {
@@ -47,6 +53,19 @@ function showGalleryImage(relUrl) {
       newImage.style.opacity = 0;  // Start fully transparent
       newImage.id = 'gallery-modal-content';
 
+      // Add pinch-to-zoom event listeners
+      newImage.addEventListener('touchstart', handlePinchStart, { passive: false });
+      newImage.addEventListener('touchmove', handlePinchMove, { passive: false });
+      newImage.addEventListener('touchend', handlePinchEnd, { passive: false });
+      newImage.addEventListener('click', handleGalleryImageClick);
+
+
+      // Reset pinch variables for the new image
+      initialPinchDistance = null;
+      initialScale = 1;
+      currentScale = 1;
+      pinchZoomOccurred = false;
+  
       // Append new image on top of existing ones
       modal.appendChild(newImage);
   
@@ -100,21 +119,28 @@ function closeGalleryModal() {
 }
 
 function handleGalleryImageClick(e) {
+  // If a pinch zoom occurred, don't change the image.
+  if (pinchZoomOccurred) {
+    pinchZoomOccurred = false; // Reset the flag for the next gesture.
+    e.stopPropagation();
+    return;
+  }
+  
   if (e.target.classList.contains('gallery-next') || e.target.classList.contains('gallery-prev')) {
-      return; // Prevent conflict
+    return; // Prevent conflict with navigation buttons.
   }
 
   const imgRect = this.getBoundingClientRect();
   if (e.clientX < imgRect.left + imgRect.width / 2) {
-      if (currentGalleryIndex > 0) {
-          currentGalleryIndex--;
-          showGalleryImage(currentGalleryImages[currentGalleryIndex]);
-      }
+    if (currentGalleryIndex > 0) {
+      currentGalleryIndex--;
+      showGalleryImage(currentGalleryImages[currentGalleryIndex]);
+    }
   } else {
-      if (currentGalleryIndex < currentGalleryImages.length - 1) {
-          currentGalleryIndex++;
-          showGalleryImage(currentGalleryImages[currentGalleryIndex]);
-      }
+    if (currentGalleryIndex < currentGalleryImages.length - 1) {
+      currentGalleryIndex++;
+      showGalleryImage(currentGalleryImages[currentGalleryIndex]);
+    }
   }
 }
 
@@ -127,10 +153,18 @@ function initGallerySwipe() {
   const galleryModal = document.getElementById('gallery-modal');
 
   galleryModal.addEventListener('touchstart', function(e) {
+    // If more than one finger is on screen, ignore swipe tracking.
+    if (e.touches.length > 1) {
+      return;
+    }
     touchStartX = e.changedTouches[0].screenX;
   }, false);
 
   galleryModal.addEventListener('touchend', function(e) {
+    // If the event was part of a multi-touch (pinch) gesture or a pinch was detected, skip swipe.
+    if (e.changedTouches.length > 1 || isPinching || pinchZoomOccurred) {
+      return;
+    }
     touchEndX = e.changedTouches[0].screenX;
     handleSwipe();
   }, false);
@@ -153,6 +187,41 @@ function initGallerySwipe() {
   }
 }
 
+function handlePinchStart(e) {
+  if (e.touches.length === 2) {
+    e.preventDefault();
+    isPinching = true;
+    pinchZoomOccurred = false; // Reset at the start of a pinch gesture.
+    const dx = e.touches[0].pageX - e.touches[1].pageX;
+    const dy = e.touches[0].pageY - e.touches[1].pageY;
+    initialPinchDistance = Math.sqrt(dx * dx + dy * dy);
+  }
+}
+
+function handlePinchMove(e) {
+  if (e.touches.length === 2 && initialPinchDistance) {
+    e.preventDefault();
+    const dx = e.touches[0].pageX - e.touches[1].pageX;
+    const dy = e.touches[0].pageY - e.touches[1].pageY;
+    const currentDistance = Math.sqrt(dx * dx + dy * dy);
+    let scale = currentDistance / initialPinchDistance;
+    scale = Math.max(0.5, Math.min(scale * initialScale, 3));
+    // If the scale has changed enough, mark that a pinch zoom occurred.
+    if (Math.abs(scale - initialScale) > 0.05) {
+      pinchZoomOccurred = true;
+    }
+    currentScale = scale;
+    e.currentTarget.style.transform = `translate(-50%, -50%) scale(${scale})`;
+  }
+}
+
+function handlePinchEnd(e) {
+  if (e.touches.length < 2) {
+    initialScale = currentScale;
+    initialPinchDistance = null;
+    isPinching = false;
+  }
+}
 
 
 
@@ -186,10 +255,7 @@ function initGalleryControls() {
 
 
 function initGallery() {
-  const galleryImage = document.getElementById('gallery-modal-content');
-  if (galleryImage) {
-    galleryImage.addEventListener('click', handleGalleryImageClick);
-  }
+
   initGallerySwipe();
   initGalleryControls();
 

templates/app.html

@@ -90,10 +90,10 @@
   
   <!-- Gallery Modal for Images -->
   <div id="gallery-modal" style="display: none;">
+    <button id="gallery-close">x</button>
     <img id="gallery-modal-content" src="" />
     <button class="gallery-nav gallery-prev">‹</button>
     <button class="gallery-nav gallery-next">›</button>
-    <button id="gallery-close">x</button>
   </div>
   
   <div id="loader-container" style="display: none;">