Draft: cartopy projections

When specifying what projection to use when plotting, users currently have to provide as string identifying which cartopy projection they wish to use. These changes allow the user to instead provide a cartopy projection object. This allows them to fine tune the projection with key word arguments, something that is not currently easily done.

scripts/pyic_view.py

@@ -164,6 +164,25 @@ class view(object):
         res_menu.grid(row=3, column=0)
         res_menu.bind("<<ComboboxSelected>>", self.make_new_axis)
 
+        # Button to activate zoom mode
+        self.zoom_button = ttk.Button(root, text="Enable Zoom", command=self.activate_zoom)
+        self.zoom_button.grid(row=3, column=2)
+
+        # Variables to store zoom area
+        self.press_event = None
+        self.rect = None
+
+        # Variables to store zoom area
+        self.press_event = None
+        self.rect = None
+
+        # proj entry
+        print('Setup proj dropdown')
+        res_menu = ttk.Combobox(root, textvariable=self.selected_proj, 
+            values=self.proj_all, state="readonly")
+        res_menu.grid(row=3, column=3)
+        res_menu.bind("<<ComboboxSelected>>", self.make_new_axis)
+
         # initial plot
         self.plot_data()
         self.canvas.draw()
@@ -173,6 +192,54 @@ class view(object):
         root.mainloop()
         return
 
+    # for zoom
+    def activate_zoom(self):
+        """Activates zooming mode by connecting event handlers."""
+        self.cid_press = self.canvas.mpl_connect("button_press_event", self.on_press)
+        self.cid_release = self.canvas.mpl_connect("button_release_event", self.on_release)
+        self.cid_motion = self.canvas.mpl_connect("motion_notify_event", self.on_motion)
+
+    # for zoom
+    def on_press(self, event):
+        """Stores the initial click position."""
+        if event.xdata is not None and event.ydata is not None:
+            self.press_event = (event.xdata, event.ydata)
+            self.rect = self.ax.add_patch(plt.Rectangle(self.press_event, 0, 0, fill=False, color="red", linestyle="dashed"))
+            self.canvas.draw()
+
+    # for zoom
+    def on_motion(self, event):
+        """Updates the rectangle while dragging."""
+        if self.press_event and event.xdata is not None and event.ydata is not None:
+            x0, y0 = self.press_event
+            width = event.xdata - x0
+            height = event.ydata - y0
+            self.rect.set_width(width)
+            self.rect.set_height(height)
+            self.canvas.draw()
+
+    # for zoom
+    def on_release(self, event):
+        """Zooms into the selected rectangle and removes it."""
+        if self.press_event and event.xdata is not None and event.ydata is not None:
+            x0, y0 = self.press_event
+            x1, y1 = event.xdata, event.ydata
+
+            # Ensure correct ordering of coordinates
+            self.ax.set_xlim(min(x0, x1), max(x0, x1))
+            self.ax.set_ylim(min(y0, y1), max(y0, y1))
+
+            # Remove the rectangle and redraw
+            self.rect.remove()
+            self.rect = None
+            self.press_event = None
+            self.canvas.draw()
+
+            # Disable event handlers after zooming
+            self.canvas.mpl_disconnect(self.cid_press)
+            self.canvas.mpl_disconnect(self.cid_release)
+            self.canvas.mpl_disconnect(self.cid_motion)
+
     def load_data(self):
         print('opening dataset')
         mfdset_kwargs = dict(