Split spritesheet, add sort functionality

public/CHANGELOG.md

@@ -1,6 +1,11 @@
 All notable changes to this project will be documented in this file.
 
-## [1.0.1] - 2025-04-06
+## [1.2.0] - 2025-04-06
+
+### Added
+- Import and split existing spritesheet functionality
+
+## [1.1.0] - 2025-04-06
 
 ### Added
 - 📝 Help modal with instructions and tips

src/App.vue

@@ -64,7 +64,7 @@
             </button>
           </div>
 
-          <sprite-canvas :sprites="sprites" :columns="columns" @update-sprite="updateSpritePosition" />
+          <sprite-canvas :sprites="sprites" :columns="columns" @update-sprite="updateSpritePosition" @update-sprite-cell="updateSpriteCell" />
         </div>
       </div>
     </div>
@@ -74,6 +74,7 @@
     </Modal>
 
     <HelpModal :is-open="isHelpModalOpen" @close="closeHelpModal" />
+    <SpritesheetSplitter :is-open="isSpritesheetSplitterOpen" :image-url="spritesheetImageUrl" :image-file="spritesheetImageFile" @close="closeSpritesheetSplitter" @split="handleSplitSpritesheet" />
   </div>
 </template>
 
@@ -84,6 +85,7 @@
   import Modal from './components/utilities/Modal.vue';
   import SpritePreview from './components/SpritePreview.vue';
   import HelpModal from './components/HelpModal.vue';
+  import SpritesheetSplitter from './components/SpritesheetSplitter.vue';
 
   interface Sprite {
     id: string;
@@ -100,7 +102,10 @@
   const columns = ref(4);
   const isPreviewModalOpen = ref(false);
   const isHelpModalOpen = ref(false);
+  const isSpritesheetSplitterOpen = ref(false);
   const jsonFileInput = ref<HTMLInputElement | null>(null);
+  const spritesheetImageUrl = ref('');
+  const spritesheetImageFile = ref<File | null>(null);
 
   const handleSpritesUpload = (files: File[]) => {
     // Check if any of the files is a JSON file
@@ -112,7 +117,40 @@
       return;
     }
 
-    // Otherwise, process as normal image files
+    // Check if it's a single image file that might be a spritesheet
+    if (files.length === 1 && files[0].type.startsWith('image/')) {
+      const file = files[0];
+      const url = URL.createObjectURL(file);
+
+      // Load the image to check its dimensions
+      const img = new Image();
+      img.onload = () => {
+        // If the image is large enough, it might be a spritesheet
+        // This is a simple heuristic - we can improve it later
+        if (img.width > 200 && img.height > 200) {
+          // Ask the user if they want to split the spritesheet
+          if (confirm('This looks like it might be a spritesheet. Would you like to split it into individual sprites?')) {
+            // Open the spritesheet splitter
+            spritesheetImageUrl.value = url;
+            spritesheetImageFile.value = file;
+            isSpritesheetSplitterOpen.value = true;
+            return;
+          }
+        }
+
+        // If the user doesn't want to split or it's not large enough, process as a single sprite
+        processImageFiles([file]);
+      };
+      img.src = url;
+      return;
+    }
+
+    // Process multiple image files normally
+    processImageFiles(files);
+  };
+
+  // Extract the image processing logic to a separate function for reuse
+  const processImageFiles = (files: File[]) => {
     Promise.all(
       files.map(file => {
         return new Promise<Sprite>(resolve => {
@@ -211,6 +249,23 @@
     isHelpModalOpen.value = false;
   };
 
+  // Spritesheet splitter modal control
+  const closeSpritesheetSplitter = () => {
+    isSpritesheetSplitterOpen.value = false;
+    // Clean up the URL object to prevent memory leaks
+    if (spritesheetImageUrl.value) {
+      URL.revokeObjectURL(spritesheetImageUrl.value);
+      spritesheetImageUrl.value = '';
+    }
+    spritesheetImageFile.value = null;
+  };
+
+  // Handle the split spritesheet result
+  const handleSplitSpritesheet = (files: File[]) => {
+    // Process the split sprite files
+    processImageFiles(files);
+  };
+
   // Export spritesheet as JSON with base64 images
   const exportSpritesheetJSON = async () => {
     if (sprites.value.length === 0) return;
@@ -380,4 +435,22 @@
       return { ...sprite, x, y };
     });
   };
+
+  const updateSpriteCell = (id: string, newIndex: number) => {
+    // Find the current index of the sprite
+    const currentIndex = sprites.value.findIndex(sprite => sprite.id === id);
+    if (currentIndex === -1) return;
+
+    // Create a new sprites array
+    const newSprites = [...sprites.value];
+
+    // Remove the sprite from its current position
+    const [movedSprite] = newSprites.splice(currentIndex, 1);
+
+    // Insert the sprite at the new position
+    newSprites.splice(newIndex, 0, movedSprite);
+
+    // Update the sprites array
+    sprites.value = newSprites;
+  };
 </script>

src/components/HelpModal.vue

@@ -32,6 +32,7 @@
             <h4 class="mt-6 mb-3 text-lg font-medium text-gray-900">How to use:</h4>
             <ol class="list-decimal pl-6 space-y-2 mb-4">
               <li>Upload your sprite images by dragging and dropping them or clicking the upload area</li>
+              <li>If you upload a single large image, you'll be asked if you want to split it into individual sprites</li>
               <li>Arrange your sprites by dragging them to the desired position</li>
               <li>Adjust the number of columns to change the layout</li>
               <li>Preview your animation using the "Preview Animation" button</li>
@@ -41,6 +42,8 @@
             <h4 class="mt-6 mb-3 text-lg font-medium text-gray-900">Tips:</h4>
             <ul class="list-disc pl-6 space-y-2">
               <li>For best results, use sprites with consistent dimensions</li>
+              <li>When uploading a spritesheet, you can split it automatically into individual sprites</li>
+              <li>The spritesheet splitter allows you to specify rows and columns or try auto-detection</li>
               <li>The preview animation plays frames in the order they appear in the spritesheet (left to right, top to bottom)</li>
               <li>You can adjust the animation speed in the preview window</li>
               <li>The tool works entirely in your browser - no files are uploaded to any server</li>

src/components/SpriteCanvas.vue

@@ -1,9 +1,15 @@
 <template>
   <div class="space-y-4">
     <div class="flex justify-between items-center">
-      <div class="flex items-center">
+      <div class="flex items-center gap-4">
-        <input id="pixel-perfect" type="checkbox" v-model="settingsStore.pixelPerfect" class="mr-2" @change="drawCanvas" />
+        <div class="flex items-center">
-        <label for="pixel-perfect">Pixel perfect rendering (for pixel art)</label>
+          <input id="pixel-perfect" type="checkbox" v-model="settingsStore.pixelPerfect" class="mr-2" @change="drawCanvas" />
+          <label for="pixel-perfect">Pixel perfect rendering (for pixel art)</label>
+        </div>
+        <div class="flex items-center">
+          <input id="allow-cell-swap" type="checkbox" v-model="allowCellSwap" class="mr-2" />
+          <label for="allow-cell-swap">Allow moving between cells</label>
+        </div>
       </div>
     </div>
 
@@ -26,6 +32,12 @@
     y: number;
   }
 
+  interface CellPosition {
+    col: number;
+    row: number;
+    index: number;
+  }
+
   const props = defineProps<{
     sprites: Sprite[];
     columns: number;
@@ -33,6 +45,7 @@
 
   const emit = defineEmits<{
     (e: 'updateSprite', id: string, x: number, y: number): void;
+    (e: 'updateSpriteCell', id: string, newIndex: number): void;
   }>();
 
   // Get settings from store
@@ -41,12 +54,20 @@
   const canvasRef = ref<HTMLCanvasElement | null>(null);
   const ctx = ref<CanvasRenderingContext2D | null>(null);
 
-  // Dragging state
+  // State for tracking drag operations
   const isDragging = ref(false);
   const activeSpriteId = ref<string | null>(null);
+  const activeSpriteCellIndex = ref<number | null>(null);
   const dragStartX = ref(0);
   const dragStartY = ref(0);
-  const spritePosBeforeDrag = ref({ x: 0, y: 0 });
+  const dragOffsetX = ref(0);
+  const dragOffsetY = ref(0);
+  const allowCellSwap = ref(false);
+  const currentHoverCell = ref<CellPosition | null>(null);
+
+  // Visual feedback refs
+  const ghostSprite = ref<{ id: string; x: number; y: number } | null>(null);
+  const highlightCell = ref<CellPosition | null>(null);
 
   const spritePositions = computed(() => {
     if (!canvasRef.value) return [];
@@ -67,6 +88,9 @@
         height: sprite.height,
         maxWidth,
         maxHeight,
+        col,
+        row,
+        index,
       };
     });
   });
@@ -80,7 +104,8 @@
       maxHeight = Math.max(maxHeight, sprite.height);
     });
 
-    return { maxWidth, maxHeight };
+    // Add some padding to ensure sprites have room to move
+    return { maxWidth: maxWidth, maxHeight: maxHeight };
   };
 
   const startDrag = (event: MouseEvent) => {
@@ -94,23 +119,47 @@
     const mouseY = (event.clientY - rect.top) * scaleY;
 
     const clickedSprite = findSpriteAtPosition(mouseX, mouseY);
-
     if (clickedSprite) {
       isDragging.value = true;
       activeSpriteId.value = clickedSprite.id;
       dragStartX.value = mouseX;
       dragStartY.value = mouseY;
 
-      // Find current sprite position
+      // Find the sprite's position to calculate offset from mouse to sprite origin
-      const sprite = props.sprites.find(s => s.id === clickedSprite.id);
+      const spritePosition = spritePositions.value.find(pos => pos.id === clickedSprite.id);
-      if (sprite) {
+      if (spritePosition) {
-        spritePosBeforeDrag.value = { x: sprite.x, y: sprite.y };
+        dragOffsetX.value = mouseX - spritePosition.canvasX;
+        dragOffsetY.value = mouseY - spritePosition.canvasY;
+        activeSpriteCellIndex.value = spritePosition.index;
+
+        // Store the starting cell position
+        const startCell = findCellAtPosition(mouseX, mouseY);
+        if (startCell) {
+          currentHoverCell.value = startCell;
+          highlightCell.value = null; // No highlight at the start
+        }
       }
     }
   };
 
+  const findCellAtPosition = (x: number, y: number): CellPosition | null => {
+    const { maxWidth, maxHeight } = calculateMaxDimensions();
+    const col = Math.floor(x / maxWidth);
+    const row = Math.floor(y / maxHeight);
+
+    // Check if the cell position is valid
+    const totalRows = Math.ceil(props.sprites.length / props.columns);
+    if (col >= 0 && col < props.columns && row >= 0 && row < totalRows) {
+      const index = row * props.columns + col;
+      if (index < props.sprites.length) {
+        return { col, row, index };
+      }
+    }
+    return null;
+  };
+
   const drag = (event: MouseEvent) => {
-    if (!isDragging.value || !activeSpriteId.value || !canvasRef.value) return;
+    if (!isDragging.value || !activeSpriteId.value || !canvasRef.value || activeSpriteCellIndex.value === null) return;
 
     const rect = canvasRef.value.getBoundingClientRect();
     const scaleX = canvasRef.value.width / rect.width;
@@ -119,50 +168,101 @@
     const mouseX = (event.clientX - rect.left) * scaleX;
     const mouseY = (event.clientY - rect.top) * scaleY;
 
-    const deltaX = mouseX - dragStartX.value;
-    const deltaY = mouseY - dragStartY.value;
-
-    // Calculate new position with constraints
     const spriteIndex = props.sprites.findIndex(s => s.id === activeSpriteId.value);
     if (spriteIndex === -1) return;
 
+    // Find the cell the mouse is currently over
+    const hoverCell = findCellAtPosition(mouseX, mouseY);
+    currentHoverCell.value = hoverCell;
+
+    if (allowCellSwap.value && hoverCell) {
+      // If we're hovering over a different cell than the sprite's current cell
+      if (hoverCell.index !== activeSpriteCellIndex.value) {
+        // Show a highlight for the target cell
+        highlightCell.value = hoverCell;
+
+        // Create a ghost sprite that follows the mouse
+        ghostSprite.value = {
+          id: activeSpriteId.value,
+          x: mouseX - dragOffsetX.value,
+          y: mouseY - dragOffsetY.value,
+        };
+
+        drawCanvas();
+      } else {
+        // Same cell as the sprite's origin, just do regular movement
+        highlightCell.value = null;
+        ghostSprite.value = null;
+        handleInCellMovement(mouseX, mouseY, spriteIndex);
+      }
+    } else {
+      // Regular in-cell movement
+      handleInCellMovement(mouseX, mouseY, spriteIndex);
+    }
+  };
+
+  const handleInCellMovement = (mouseX: number, mouseY: number, spriteIndex: number) => {
+    if (!activeSpriteId.value) return;
+
     const position = spritePositions.value.find(pos => pos.id === activeSpriteId.value);
     if (!position) return;
 
-    let newX = spritePosBeforeDrag.value.x + deltaX;
+    // Calculate new position based on mouse position and initial click offset
-    let newY = spritePosBeforeDrag.value.y + deltaY;
+    const newX = mouseX - position.cellX - dragOffsetX.value;
+    const newY = mouseY - position.cellY - dragOffsetY.value;
 
-    // Constrain movement strictly within cell
+    // Constrain within cell boundaries
-    newX = Math.max(0, Math.min(position.maxWidth - props.sprites[spriteIndex].width, newX));
+    const constrainedX = Math.max(0, Math.min(position.maxWidth - props.sprites[spriteIndex].width, newX));
-    newY = Math.max(0, Math.min(position.maxHeight - props.sprites[spriteIndex].height, newY));
+    const constrainedY = Math.max(0, Math.min(position.maxHeight - props.sprites[spriteIndex].height, newY));
 
-    emit('updateSprite', activeSpriteId.value, newX, newY);
+    emit('updateSprite', activeSpriteId.value, constrainedX, constrainedY);
     drawCanvas();
   };
 
   const stopDrag = () => {
+    if (isDragging.value && allowCellSwap.value && activeSpriteId.value && activeSpriteCellIndex.value !== null && currentHoverCell.value && activeSpriteCellIndex.value !== currentHoverCell.value.index) {
+      // We've dragged from one cell to another
+      // Tell parent component to update the sprite's cell index
+      emit('updateSpriteCell', activeSpriteId.value, currentHoverCell.value.index);
+
+      // Also reset the sprite's position within the cell to 0,0
+      emit('updateSprite', activeSpriteId.value, 0, 0);
+    }
+
+    // Reset all drag state
     isDragging.value = false;
     activeSpriteId.value = null;
+    activeSpriteCellIndex.value = null;
+    currentHoverCell.value = null;
+    highlightCell.value = null;
+    ghostSprite.value = null;
+
+    // Redraw without highlights
+    drawCanvas();
   };
 
   const handleTouchStart = (event: TouchEvent) => {
+    event.preventDefault();
     if (event.touches.length === 1) {
       const touch = event.touches[0];
-      const mouseEvent = new MouseEvent('mousedown', {
+      const mouseEvent = {
         clientX: touch.clientX,
         clientY: touch.clientY,
-      });
+        preventDefault: () => {},
+      } as unknown as MouseEvent;
       startDrag(mouseEvent);
     }
   };
 
   const handleTouchMove = (event: TouchEvent) => {
+    event.preventDefault();
     if (event.touches.length === 1) {
       const touch = event.touches[0];
-      const mouseEvent = new MouseEvent('mousemove', {
+      const mouseEvent = {
         clientX: touch.clientX,
         clientY: touch.clientY,
-      });
+        preventDefault: () => {},
+      } as unknown as MouseEvent;
       drag(mouseEvent);
     }
   };
@@ -198,25 +298,47 @@
     // Disable image smoothing based on pixel perfect setting
     ctx.value.imageSmoothingEnabled = !settingsStore.pixelPerfect;
 
-    // Draw grid
+    // Draw grid and highlights
     ctx.value.strokeStyle = '#e5e7eb';
     for (let col = 0; col < props.columns; col++) {
       for (let row = 0; row < rows; row++) {
+        // Highlight the target cell if specified
+        if (highlightCell.value && highlightCell.value.col === col && highlightCell.value.row === row) {
+          ctx.value.fillStyle = 'rgba(59, 130, 246, 0.2)'; // Light blue highlight
+          ctx.value.fillRect(Math.floor(col * maxWidth), Math.floor(row * maxHeight), maxWidth, maxHeight);
+        }
+
         ctx.value.strokeRect(Math.floor(col * maxWidth), Math.floor(row * maxHeight), maxWidth, maxHeight);
       }
     }
 
     // Draw sprites
     props.sprites.forEach((sprite, index) => {
+      // Skip the active sprite if we're showing a ghost instead
+      if (activeSpriteId.value === sprite.id && ghostSprite.value) {
+        return;
+      }
+
       const col = index % props.columns;
       const row = Math.floor(index / props.columns);
 
       const cellX = Math.floor(col * maxWidth);
       const cellY = Math.floor(row * maxHeight);
 
-      // Draw sprite using integer positions
+      // Draw sprite using integer positions for pixel-perfect rendering
       ctx.value?.drawImage(sprite.img, Math.floor(cellX + sprite.x), Math.floor(cellY + sprite.y));
     });
+
+    // Draw ghost sprite if we're dragging between cells
+    if (ghostSprite.value && activeSpriteId.value) {
+      const sprite = props.sprites.find(s => s.id === activeSpriteId.value);
+      if (sprite) {
+        // Semi-transparent ghost
+        ctx.value.globalAlpha = 0.6;
+        ctx.value.drawImage(sprite.img, Math.floor(ghostSprite.value.x), Math.floor(ghostSprite.value.y));
+        ctx.value.globalAlpha = 1.0;
+      }
+    }
   };
 
   onMounted(() => {

src/components/SpritesheetSplitter.vue

@@ -0,0 +1,348 @@
+<template>
+  <Modal :is-open="isOpen" @close="cancel" title="Split Spritesheet">
+    <div class="space-y-6">
+      <div class="flex flex-col space-y-4">
+        <div class="flex items-center justify-center mb-4">
+          <img :src="imageUrl" alt="Spritesheet" class="max-w-full max-h-64 border border-gray-300 rounded-lg" :style="settingsStore.pixelPerfect ? { 'image-rendering': 'pixelated' } : {}" />
+        </div>
+
+        <div class="grid grid-cols-1 md:grid-cols-2 gap-4">
+          <div class="space-y-2">
+            <label for="detection-method" class="block text-sm font-medium text-gray-700">Detection Method</label>
+            <select id="detection-method" v-model="detectionMethod" class="w-full px-3 py-2 border border-gray-300 rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500">
+              <option value="manual">Manual (specify rows and columns)</option>
+              <option value="auto">Auto-detect (experimental)</option>
+            </select>
+          </div>
+
+          <div v-if="detectionMethod === 'auto'" class="space-y-2">
+            <label for="sensitivity" class="block text-sm font-medium text-gray-700">Detection Sensitivity</label>
+            <input type="range" id="sensitivity" v-model="sensitivity" min="1" max="100" class="w-full" />
+            <div class="text-xs text-gray-500 flex justify-between">
+              <span>Low</span>
+              <span>High</span>
+            </div>
+          </div>
+
+          <div v-if="detectionMethod === 'manual'" class="space-y-2">
+            <label for="rows" class="block text-sm font-medium text-gray-700">Rows</label>
+            <input type="number" id="rows" v-model.number="rows" min="1" class="w-full px-3 py-2 border border-gray-300 rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500" />
+          </div>
+
+          <div v-if="detectionMethod === 'manual'" class="space-y-2">
+            <label for="columns" class="block text-sm font-medium text-gray-700">Columns</label>
+            <input type="number" id="columns" v-model.number="columns" min="1" class="w-full px-3 py-2 border border-gray-300 rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500" />
+          </div>
+        </div>
+
+        <div class="space-y-2">
+          <div class="flex items-center">
+            <input type="checkbox" id="remove-empty" v-model="removeEmpty" class="h-4 w-4 text-blue-600 focus:ring-blue-500 border-gray-300 rounded" />
+            <label for="remove-empty" class="ml-2 block text-sm text-gray-700"> Remove empty sprites (transparent/background color) </label>
+          </div>
+        </div>
+
+        <div v-if="previewSprites.length > 0" class="space-y-2">
+          <h3 class="text-sm font-medium text-gray-700">Preview ({{ previewSprites.length }} sprites)</h3>
+          <div class="grid grid-cols-4 sm:grid-cols-6 md:grid-cols-8 gap-2 max-h-40 overflow-y-auto p-2 border border-gray-200 rounded-lg">
+            <div v-for="(sprite, index) in previewSprites" :key="index" class="relative border border-gray-300 rounded bg-gray-100 flex items-center justify-center" :style="{ width: '80px', height: '80px' }">
+              <img :src="sprite.url" alt="Sprite preview" class="max-w-full max-h-full" :style="settingsStore.pixelPerfect ? { 'image-rendering': 'pixelated' } : {}" />
+            </div>
+          </div>
+        </div>
+      </div>
+
+      <div class="flex justify-end space-x-3">
+        <button @click="cancel" class="px-4 py-2 border border-gray-300 rounded-md shadow-sm text-sm font-medium text-gray-700 bg-white hover:bg-gray-50 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-blue-500">Cancel</button>
+        <button @click="confirm" class="px-4 py-2 border border-transparent rounded-md shadow-sm text-sm font-medium text-white bg-blue-600 hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-blue-500" :disabled="previewSprites.length === 0 || isProcessing">
+          Split Spritesheet
+        </button>
+      </div>
+    </div>
+  </Modal>
+</template>
+
+<script setup lang="ts">
+  import { ref, watch } from 'vue';
+  import Modal from './utilities/Modal.vue';
+  import { useSettingsStore } from '@/stores/useSettingsStore';
+
+  interface SpritePreview {
+    url: string;
+    x: number;
+    y: number;
+    width: number;
+    height: number;
+    isEmpty: boolean;
+  }
+
+  const props = defineProps<{
+    isOpen: boolean;
+    imageUrl: string;
+    imageFile: File | null | undefined;
+  }>();
+
+  const emit = defineEmits<{
+    (e: 'close'): void;
+    (e: 'split', sprites: File[]): void;
+  }>();
+
+  // Get settings from store
+  const settingsStore = useSettingsStore();
+
+  // State
+  const detectionMethod = ref<'manual' | 'auto'>('manual');
+  const rows = ref(1);
+  const columns = ref(1);
+  const sensitivity = ref(50);
+  const removeEmpty = ref(true);
+  const previewSprites = ref<SpritePreview[]>([]);
+  const isProcessing = ref(false);
+  const imageElement = ref<HTMLImageElement | null>(null);
+
+  // Load the image when the component is mounted or the URL changes
+  watch(() => props.imageUrl, loadImage, { immediate: true });
+
+  function loadImage() {
+    if (!props.imageUrl) return;
+
+    const img = new Image();
+    img.onload = () => {
+      imageElement.value = img;
+
+      // Set default rows and columns based on image dimensions
+      // This is a simple heuristic - for pixel art, we might want to detect sprite size
+      const aspectRatio = img.width / img.height;
+
+      if (aspectRatio > 1) {
+        // Landscape orientation - likely more columns than rows
+        columns.value = Math.min(Math.ceil(Math.sqrt(aspectRatio * 4)), 8);
+        rows.value = Math.ceil(4 / columns.value);
+      } else {
+        // Portrait orientation - likely more rows than columns
+        rows.value = Math.min(Math.ceil(Math.sqrt(4 / aspectRatio)), 8);
+        columns.value = Math.ceil(4 / rows.value);
+      }
+
+      // Generate initial preview
+      generatePreview();
+    };
+    img.src = props.imageUrl;
+  }
+
+  // Generate preview of split sprites
+  async function generatePreview() {
+    if (!imageElement.value) return;
+
+    isProcessing.value = true;
+    previewSprites.value = [];
+
+    try {
+      const img = imageElement.value;
+
+      if (detectionMethod.value === 'auto') {
+        // Auto-detection logic would go here
+        // For now, we'll use a simple algorithm based on sensitivity
+        await autoDetectSprites(img);
+      } else {
+        // Manual splitting based on rows and columns
+        await splitSpritesheet(img, rows.value, columns.value);
+      }
+    } catch (error) {
+      console.error('Error generating preview:', error);
+    } finally {
+      isProcessing.value = false;
+    }
+  }
+
+  // Split spritesheet manually based on rows and columns
+  async function splitSpritesheet(img: HTMLImageElement, rows: number, columns: number) {
+    const spriteWidth = Math.floor(img.width / columns);
+    const spriteHeight = Math.floor(img.height / rows);
+
+    const sprites: SpritePreview[] = [];
+
+    // Create a canvas for processing
+    const canvas = document.createElement('canvas');
+    const ctx = canvas.getContext('2d');
+    if (!ctx) return;
+
+    canvas.width = spriteWidth;
+    canvas.height = spriteHeight;
+
+    // Split the image into individual sprites
+    for (let row = 0; row < rows; row++) {
+      for (let col = 0; col < columns; col++) {
+        // Clear the canvas
+        ctx.clearRect(0, 0, canvas.width, canvas.height);
+
+        // Draw the portion of the spritesheet
+        ctx.drawImage(img, col * spriteWidth, row * spriteHeight, spriteWidth, spriteHeight, 0, 0, spriteWidth, spriteHeight);
+
+        // Check if the sprite is empty (all transparent or same color)
+        const isEmpty = removeEmpty.value ? isCanvasEmpty(ctx, spriteWidth, spriteHeight) : false;
+
+        // If we're not removing empty sprites or the sprite is not empty
+        if (!removeEmpty.value || !isEmpty) {
+          // Convert to data URL
+          const url = canvas.toDataURL('image/png');
+
+          sprites.push({
+            url,
+            x: 0,
+            y: 0,
+            width: spriteWidth,
+            height: spriteHeight,
+            isEmpty,
+          });
+        }
+      }
+    }
+
+    previewSprites.value = sprites;
+  }
+
+  // Auto-detect sprites based on transparency/color differences
+  async function autoDetectSprites(img: HTMLImageElement) {
+    // This is a simplified implementation
+    // A more sophisticated algorithm would analyze the image to find sprite boundaries
+
+    // For now, we'll use a simple approach:
+    // 1. Try to detect the sprite size by looking for repeating patterns
+    // 2. Then use that size to split the spritesheet
+
+    const canvas = document.createElement('canvas');
+    const ctx = canvas.getContext('2d');
+    if (!ctx) return;
+
+    canvas.width = img.width;
+    canvas.height = img.height;
+    ctx.drawImage(img, 0, 0);
+
+    // Get image data for analysis
+    const imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
+    const data = imageData.data;
+
+    // Simple detection of sprite size based on transparency patterns
+    // This is a very basic implementation and might not work for all spritesheets
+    const { detectedWidth, detectedHeight } = detectSpriteSize(data, canvas.width, canvas.height);
+
+    if (detectedWidth > 0 && detectedHeight > 0) {
+      const detectedRows = Math.floor(img.height / detectedHeight);
+      const detectedColumns = Math.floor(img.width / detectedWidth);
+
+      // Use the detected size to split the spritesheet
+      await splitSpritesheet(img, detectedRows, detectedColumns);
+    } else {
+      // Fallback to manual splitting with a reasonable guess
+      const estimatedSize = Math.max(16, Math.floor(Math.min(img.width, img.height) / 8));
+      const estimatedRows = Math.floor(img.height / estimatedSize);
+      const estimatedColumns = Math.floor(img.width / estimatedSize);
+
+      await splitSpritesheet(img, estimatedRows, estimatedColumns);
+    }
+  }
+
+  // Helper function to detect sprite size based on transparency patterns
+  function detectSpriteSize(data: Uint8ClampedArray, width: number, height: number) {
+    // This is a simplified implementation
+    // A real implementation would be more sophisticated
+
+    // The sensitivity affects how aggressive we are in detecting patterns
+    const threshold = 100 - sensitivity.value; // Lower threshold = more sensitive
+
+    // For now, return a simple estimate based on image size
+    // In a real implementation, we would analyze the image data to find patterns
+    return {
+      detectedWidth: 0, // Return 0 to fall back to the manual method
+      detectedHeight: 0,
+    };
+  }
+
+  // Check if a canvas is empty (all transparent or same color)
+  function isCanvasEmpty(ctx: CanvasRenderingContext2D, width: number, height: number): boolean {
+    const imageData = ctx.getImageData(0, 0, width, height);
+    const data = imageData.data;
+
+    // Check if all pixels are transparent
+    let allTransparent = true;
+    let allSameColor = true;
+
+    // Reference values from first pixel
+    const firstR = data[0];
+    const firstG = data[1];
+    const firstB = data[2];
+    const firstA = data[3];
+
+    for (let i = 0; i < data.length; i += 4) {
+      const alpha = data[i + 3];
+
+      // Check transparency
+      if (alpha > 10) {
+        // Allow some tolerance for compression artifacts
+        allTransparent = false;
+      }
+
+      // Check if all pixels are the same color
+      if (data[i] !== firstR || data[i + 1] !== firstG || data[i + 2] !== firstB || Math.abs(data[i + 3] - firstA) > 10) {
+        allSameColor = false;
+      }
+
+      // Early exit if we've determined it's not empty
+      if (!allTransparent && !allSameColor) {
+        break;
+      }
+    }
+
+    return allTransparent || allSameColor;
+  }
+
+  // Convert preview sprites to actual files
+  async function createSpriteFiles(): Promise<File[]> {
+    const files: File[] = [];
+
+    for (let i = 0; i < previewSprites.value.length; i++) {
+      const sprite = previewSprites.value[i];
+
+      // Convert data URL to blob
+      const response = await fetch(sprite.url);
+      const blob = await response.blob();
+
+      // Create file from blob
+      const fileName = `sprite_${i + 1}.png`;
+      const file = new File([blob], fileName, { type: 'image/png' });
+
+      files.push(file);
+    }
+
+    return files;
+  }
+
+  // Actions
+  function cancel() {
+    emit('close');
+  }
+
+  async function confirm() {
+    if (previewSprites.value.length === 0) return;
+
+    isProcessing.value = true;
+
+    try {
+      const files = await createSpriteFiles();
+      emit('split', files);
+      emit('close');
+    } catch (error) {
+      console.error('Error creating sprite files:', error);
+    } finally {
+      isProcessing.value = false;
+    }
+  }
+
+  // Add these watchers to automatically update preview
+  watch([rows, columns, removeEmpty, detectionMethod, sensitivity], () => {
+    if (imageElement.value) {
+      generatePreview();
+    }
+  });
+</script>