✨ feat: 最后切出来的图片，按照实际图片在瓦片的位置，而不是填充满瓦片的长宽

@@ -47,14 +47,6 @@ function sliceImageToTiles(image, bounds, zoomLevel) {
   tileStartY = Math.min(tileStartY, tileEndY);
   tileEndY = Math.max(tileStartY, tileEndY);
 
-  // console.warn(`瓦片编号: X(${tileStartX} -> ${tileEndX}), Y(${tileStartY} -> ${tileEndY})`);
-
-  const cols = tileEndX - tileStartX + 1;
-  const rows = tileEndY - tileStartY + 1;
-
-  const tileWidth = imgWidth / cols;
-  const tileHeight = imgHeight / rows;
-
   const scaleFactor = 2; // 调高分辨率倍率
 
   canvas.width = tileSize * scaleFactor;
@@ -66,14 +58,28 @@ function sliceImageToTiles(image, bounds, zoomLevel) {
 
   let tileIndex = 0;  // 瓦片索引，用来给每个瓦片命名
 
-  for (let x = 0; x < cols; x++) {
-      for (let y = 0; y < rows; y++) {
-          ctx.clearRect(0, 0, tileSize, tileSize);
+  // 计算每个瓦片的经纬度范围
+  for (let tileX = tileStartX; tileX <= tileEndX; tileX++) {
+    for (let tileY = tileStartY; tileY <= tileEndY; tileY++) {
+      // 计算当前瓦片的经纬度范围
+      const tileLonStart = tileX * 360 / Math.pow(2, zoomLevel) - 180;
+      const tileLonEnd = (tileX + 1) * 360 / Math.pow(2, zoomLevel) - 180;
+      const tileLatStart = Math.atan(Math.sinh(Math.PI * (1 - 2 * (tileY + 1) / Math.pow(2, zoomLevel)))) * 180 / Math.PI;
+      const tileLatEnd = Math.atan(Math.sinh(Math.PI * (1 - 2 * tileY / Math.pow(2, zoomLevel)))) * 180 / Math.PI;
+
+      // 计算图片在当前瓦片中的位置和尺寸
+      const tileImgX = (lonStart - tileLonStart) / (tileLonEnd - tileLonStart) * tileSize;
+      const tileImgY = (tileLatEnd - latEnd) / (tileLatEnd - tileLatStart) * tileSize;
+      const tileImgWidth = (lonEnd - lonStart) / (tileLonEnd - tileLonStart) * tileSize;
+      const tileImgHeight = (latEnd - latStart) / (tileLatEnd - tileLatStart) * tileSize;
+
+      ctx.clearRect(0, 0, tileSize * scaleFactor, tileSize * scaleFactor);
 
+      // 根据图片在瓦片中的实际位置和尺寸绘制
       ctx.drawImage(
         image,
-              x * tileWidth, y * tileHeight, tileWidth, tileHeight, // 源图像区域
-              0, 0, tileSize, tileSize // 目标画布区域
+        0, 0, imgWidth, imgHeight, // 源图像区域（使用完整图片）
+        tileImgX, tileImgY, tileImgWidth, tileImgHeight // 目标画布区域（保持实际位置和比例）
       );
 
       canvas.toBlob((blob) => {
@@ -81,10 +87,6 @@ function sliceImageToTiles(image, bounds, zoomLevel) {
           console.error("瓦片转换失败！");
           return;
         }
-              const tileX = tileStartX + x;
-              const tileY = tileStartY + y;
-              // console.warn(`保存瓦片: ${tileX}_${tileY}_${zoomLevel}.png`);
-              // saveTile(blob, `${tileX}_${tileY}_${zoomLevel}.png`);
 
         // 获取当前北京时间（UTC+8）
         const beijingTime = dayjs().add(8, "hour").toDate();
@@ -94,7 +96,8 @@ function sliceImageToTiles(image, bounds, zoomLevel) {
         tileIndex++;
 
         // 如果所有瓦片都处理完，生成并下载压缩包
-              if (tileIndex === cols * rows) {
+        const totalTiles = (tileEndX - tileStartX + 1) * (tileEndY - tileStartY + 1);
+        if (tileIndex === totalTiles) {
           generateAndDownloadZip(zip, zoomLevel);
         }
       }, "image/png", 1.0);