diff --git a/public/v5x5.png b/public/v5x5.png
deleted file mode 100644
index 6a9e37c..0000000
Binary files a/public/v5x5.png and /dev/null differ
diff --git a/src/App.tsx b/src/App.tsx
index 5c0dde3..186cb83 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,21 +1,85 @@
-import { useEffect, useRef, useState } from "react";
+import { useCallback, useEffect, useRef, useState } from "react";
 import L from "leaflet";
 import "leaflet/dist/leaflet.css";
 import "./App.css";
 
+const IMAGE_URL = "/V5.png";
+const INITIAL_CENTER = { lat: 43.5488, lng: 7.0176 };
+
+type BaseLayerMode = "map" | "satellite";
+
+type LatLng = {
+  lat: number;
+  lng: number;
+};
+
+type LatLngExpression = LatLng | [number, number];
+
+type LeafletPoint = {
+  x: number;
+  y: number;
+  subtract: (point: LeafletPoint) => LeafletPoint;
+  multiplyBy: (factor: number) => LeafletPoint;
+};
+
+type LeafletMap = {
+  setView: (center: [number, number], zoom: number) => LeafletMap;
+  getZoom: () => number;
+  latLngToLayerPoint: (latlng: LatLng) => LeafletPoint;
+  layerPointToLatLng: (point: LeafletPoint) => LatLng;
+  getSize: () => { x: number; y: number };
+  getPanes: () => { overlayPane: HTMLElement };
+  on: (eventName: string, handler: (event: unknown) => void) => LeafletMap;
+};
+
+type LeafletTileLayer = {
+  addTo: (map: LeafletMap) => LeafletTileLayer;
+  remove: () => LeafletTileLayer;
+};
+
+type LeafletMarker = {
+  addTo: (map: LeafletMap) => LeafletMarker;
+  bindTooltip: (
+      content: string,
+      options?: { permanent?: boolean; direction?: string }
+  ) => LeafletMarker;
+  on: (eventName: string, handler: (event: MarkerDragEvent) => void) => LeafletMarker;
+  setLatLng: (latlng: LatLngExpression) => LeafletMarker;
+};
+
+type MarkerDragEvent = {
+  target: {
+    getLatLng: () => LatLng;
+  };
+};
+
+type MapClickEvent = {
+  latlng: LatLng;
+};
+
+type Corner = {
+  name: string;
+  latlng: LatLng;
+};
+
 function App() {
   const mapRef = useRef<HTMLDivElement | null>(null);
-  const map = useRef<any>(null);
+  const map = useRef<LeafletMap | null>(null);
 
   const canvasRef = useRef<HTMLCanvasElement | null>(null);
   const imageRef = useRef<HTMLImageElement | null>(null);
+  const drawRef = useRef<() => void>(() => {});
 
-  const centerMarker = useRef<any>(null);
-  const cornerMarkers = useRef<any[]>([]);
+  const mapLayer = useRef<LeafletTileLayer | null>(null);
+  const satelliteLayer = useRef<LeafletTileLayer | null>(null);
 
-  const imageUrl = "/V5.png";
+  const centerMarker = useRef<LeafletMarker | null>(null);
+  const cornerMarkers = useRef<LeafletMarker[]>([]);
+  const pointMarker = useRef<LeafletMarker | null>(null);
 
-  const [center, setCenter] = useState({ lat: 43.5488, lng: 7.0176 });
+  const [center, setCenter] = useState(INITIAL_CENTER);
+  const [selectedPoint, setSelectedPoint] = useState<{ lat: number; lng: number } | null>(null);
+  const [baseLayerMode, setBaseLayerMode] = useState<BaseLayerMode>("map");
 
   const [rotation, setRotation] = useState(0);
   const [scale, setScale] = useState(1);
@@ -26,23 +90,74 @@ function App() {
 
   const toRad = (d: number) => (d * Math.PI) / 180;
 
-  const getMetersPerPixel = (zoom: number) =>
-      (156543.03392 * Math.cos((center.lat * Math.PI) / 180)) / Math.pow(2, zoom);
+  const getMetersPerPixel = useCallback(
+      (zoom: number) =>
+          (156543.03392 * Math.cos((center.lat * Math.PI) / 180)) / Math.pow(2, zoom),
+      [center.lat]
+  );
 
-  const getImageSizeInScreenPixels = (zoom: number) => {
+  const getImageSizeInScreenPixels = useCallback((zoom: number) => {
     const metersPerPixel = getMetersPerPixel(zoom);
 
     return {
       widthPx: (imgWidth * scale) / metersPerPixel,
       heightPx: (imgHeight * scale) / metersPerPixel,
     };
+  }, [getMetersPerPixel, imgHeight, imgWidth, scale]);
+
+  const formatCoordinate = (value: number) => value.toFixed(6);
+
+  const toggleBaseLayer = () => {
+    const currentMap = map.current;
+    if (!currentMap) return;
+
+    setBaseLayerMode((currentMode) => {
+      const nextMode = currentMode === "map" ? "satellite" : "map";
+      const currentLayer = currentMode === "map" ? mapLayer.current : satelliteLayer.current;
+      const nextLayer = nextMode === "map" ? mapLayer.current : satelliteLayer.current;
+
+      currentLayer?.remove();
+      nextLayer?.addTo(currentMap);
+
+      return nextMode;
+    });
   };
 
+  const placePoint = useCallback((latlng: LatLng) => {
+    const point = { lat: latlng.lat, lng: latlng.lng };
+    setSelectedPoint(point);
+
+    const currentMap = map.current;
+    if (!currentMap) return;
+
+    if (!pointMarker.current) {
+      const marker: LeafletMarker = L.marker([point.lat, point.lng], {
+        draggable: true,
+      })
+          .addTo(currentMap)
+          .bindTooltip("Point", {
+            permanent: true,
+            direction: "top",
+          });
+
+      marker.on("dragend", (e: MarkerDragEvent) => {
+        const p = e.target.getLatLng();
+        setSelectedPoint({ lat: p.lat, lng: p.lng });
+      });
+
+      pointMarker.current = marker;
+    } else {
+      pointMarker.current.setLatLng([point.lat, point.lng]);
+    }
+  }, []);
+
   // --------------------------------------------------
   // CORNERS (SIG CORRECT : project/unproject)
   // --------------------------------------------------
-  const computeCorners = () => {
+  const computeCorners = useCallback((): Corner[] => {
     const m = map.current;
+    if (!m) return [];
+
     const zoom = m.getZoom();
     const centerPoint = m.latLngToLayerPoint(center);
     const { widthPx, heightPx } = getImageSizeInScreenPixels(zoom);
@@ -68,13 +183,14 @@ function App() {
 
       return { name: p.name, latlng };
     });
-  };
+  }, [center, getImageSizeInScreenPixels, rotation]);
 
   // --------------------------------------------------
   // MARKERS CORNERS
   // --------------------------------------------------
-  const updateCorners = (corners: any[]) => {
+  const updateCorners = useCallback((corners: Corner[]) => {
     const m = map.current;
+    if (!m) return;
 
     corners.forEach((c, i) => {
       if (!cornerMarkers.current[i]) {
@@ -93,12 +209,12 @@ function App() {
         cornerMarkers.current[i].setLatLng(c.latlng);
       }
     });
-  };
+  }, []);
 
   // --------------------------------------------------
   // DRAW IMAGE OVERLAY
   // --------------------------------------------------
-  const draw = () => {
+  const draw = useCallback(() => {
     if (!map.current || !canvasRef.current || !imageRef.current) return;
 
     const m = map.current;
@@ -111,7 +227,9 @@ function App() {
     canvas.style.width = `${size.x}px`;
     canvas.style.height = `${size.y}px`;
 
-    const panePos = L.DomUtil.getPosition(m.getPanes().overlayPane) ?? L.point(0, 0);
+    const panePos = (
+        L.DomUtil.getPosition(m.getPanes().overlayPane) ?? L.point(0, 0)
+    ) as LeafletPoint;
     L.DomUtil.setPosition(canvas, panePos.multiplyBy(-1));
 
     ctx.clearRect(0, 0, canvas.width, canvas.height);
@@ -138,13 +256,14 @@ function App() {
 
     const corners = computeCorners();
     updateCorners(corners);
-  };
+  }, [center, computeCorners, getImageSizeInScreenPixels, opacity, rotation, updateCorners]);
 
   // --------------------------------------------------
   // EXPORT GDAL (RESTORED)
   // --------------------------------------------------
   const exportGCP = () => {
     const gcp = computeCorners();
+    if (gcp.length < 4) return;
 
     const text = `
 # GDAL GCP EXPORT
@@ -168,16 +287,28 @@ gdalwarp -r bilinear -tps new.tif newfinal.tif
   // INIT MAP
   // --------------------------------------------------
   useEffect(() => {
-    if (map.current) return;
+    drawRef.current = draw;
+  }, [draw]);
 
-    map.current = L.map(mapRef.current!).setView(
-        [center.lat, center.lng],
+  useEffect(() => {
+    if (map.current || !mapRef.current) return;
+
+    const createdMap = L.map(mapRef.current).setView(
+        [INITIAL_CENTER.lat, INITIAL_CENTER.lng],
         13
-    );
+    ) as LeafletMap;
+    map.current = createdMap;
 
-    L.tileLayer("https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png", {
+    mapLayer.current = L.tileLayer("https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png", {
       attribution: "© OSM",
-    }).addTo(map.current);
+    }).addTo(createdMap);
+
+    satelliteLayer.current = L.tileLayer(
+        "https://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer/tile/{z}/{y}/{x}",
+        {
+          attribution: "Tiles © Esri",
+        }
+    );
 
     const canvas = document.createElement("canvas");
     canvas.style.position = "absolute";
@@ -186,29 +317,35 @@ gdalwarp -r bilinear -tps new.tif newfinal.tif
     canvas.style.pointerEvents = "none";
     canvas.style.zIndex = "400";
 
-    map.current.getPanes().overlayPane.appendChild(canvas);
+    createdMap.getPanes().overlayPane.appendChild(canvas);
     canvasRef.current = canvas;
 
     imageRef.current = new Image();
-    imageRef.current.src = imageUrl;
+    imageRef.current.src = IMAGE_URL;
 
-    imageRef.current.onload = () => draw();
+    imageRef.current.onload = () => drawRef.current();
 
-    centerMarker.current = L.marker([center.lat, center.lng], {
+    const marker: LeafletMarker = L.marker([INITIAL_CENTER.lat, INITIAL_CENTER.lng], {
       draggable: true,
-    }).addTo(map.current);
+    }).addTo(createdMap);
 
-    centerMarker.current.on("drag", (e: any) => {
+    marker.on("drag", (e: MarkerDragEvent) => {
       const p = e.target.getLatLng();
       setCenter({ lat: p.lat, lng: p.lng });
     });
 
-    map.current.on("move zoom", () => draw());
-  }, []);
+    centerMarker.current = marker;
+
+    createdMap.on("click", (e: unknown) => {
+      placePoint((e as MapClickEvent).latlng);
+    });
+
+    createdMap.on("move zoom", () => drawRef.current());
+  }, [placePoint]);
 
   useEffect(() => {
     draw();
-  }, [center, rotation, scale, opacity, imgWidth, imgHeight]);
+  }, [draw]);
 
   // --------------------------------------------------
   // UI
@@ -219,6 +356,12 @@ gdalwarp -r bilinear -tps new.tif newfinal.tif
         <div style={{ width: 320, background: "#111", color: "#0f0", padding: 12 }}>
           <h3>Image control</h3>
 
+          <button onClick={toggleBaseLayer}>
+            {baseLayerMode === "map" ? "Vue satellite" : "Vue plan"}
+          </button>
+
+          <hr />
+
           <label>Width</label>
           <input
               type="number"
@@ -273,6 +416,41 @@ gdalwarp -r bilinear -tps new.tif newfinal.tif
           <button onClick={exportGCP}>
             📦 Export GDAL GCP
           </button>
+
+          <hr />
+
+          <h3>Point</h3>
+          <p>Clique sur la carte pour poser le point.</p>
+
+          {selectedPoint ? (
+              <>
+                <div>
+                  <label>Latitude</label>
+                  <input
+                      readOnly
+                      value={formatCoordinate(selectedPoint.lat)}
+                  />
+                </div>
+                <div>
+                  <label>Longitude</label>
+                  <input
+                      readOnly
+                      value={formatCoordinate(selectedPoint.lng)}
+                  />
+                </div>
+                <button
+                    onClick={() => {
+                      navigator.clipboard.writeText(
+                          `${formatCoordinate(selectedPoint.lat)}, ${formatCoordinate(selectedPoint.lng)}`
+                      );
+                    }}
+                >
+                  Copier les coordonnées
+                </button>
+              </>
+          ) : (
+              <p>Aucun point posé.</p>
+          )}
         </div>
 
         {/* MAP */}