diff --git a/src/input.cc b/src/input.cc
index ccfa5a6..1bf56ac 100644
--- a/src/input.cc
+++ b/src/input.cc
@@ -199,6 +199,13 @@ int inputGetInput()
     return -1;
 }
 
+// 0x4C8BC8
+void get_input_position(int* x, int* y)
+{
+    *x = _input_mx;
+    *y = _input_my;
+}
+
 // 0x4C8BDC
 void _process_bk()
 {
diff --git a/src/input.h b/src/input.h
index 93a0c93..5539af1 100644
--- a/src/input.h
+++ b/src/input.h
@@ -13,6 +13,7 @@ typedef int(ScreenshotHandler)(int width, int height, unsigned char* buffer, uns
 int inputInit(int a1);
 void inputExit();
 int inputGetInput();
+void get_input_position(int* x, int* y);
 void _process_bk();
 void enqueueInputEvent(int a1);
 void inputEventQueueReset();
diff --git a/src/mapper/map_func.cc b/src/mapper/map_func.cc
index 0ba769c..92a96fa 100644
--- a/src/mapper/map_func.cc
+++ b/src/mapper/map_func.cc
@@ -1,6 +1,10 @@
 #include "mapper/map_func.h"
 
+#include "color.h"
+#include "game_mouse.h"
+#include "input.h"
 #include "memory.h"
+#include "mouse.h"
 #include "proto.h"
 #include "svga.h"
 #include "window_manager.h"
@@ -22,6 +26,46 @@ void copy_proto_lists()
     // TODO: Incomplete.
 }
 
+// 0x4841C4
+void pick_region(Rect* rect)
+{
+    Rect temp;
+    int x;
+    int y;
+
+    gameMouseSetCursor(MOUSE_CURSOR_PLUS);
+    gameMouseObjectsHide();
+
+    while (1) {
+        if (inputGetInput() == -2
+            && (mouseGetEvent() & MOUSE_EVENT_LEFT_BUTTON_DOWN) != 0) {
+            break;
+        }
+    }
+
+    get_input_position(&x, &y);
+    temp.left = x;
+    temp.top = y;
+    temp.right = x;
+    temp.bottom = y;
+
+    while ((mouseGetEvent() & MOUSE_EVENT_LEFT_BUTTON_UP) == 0) {
+        inputGetInput();
+
+        get_input_position(&x, &y);
+
+        if (x != temp.right || y != temp.bottom) {
+            erase_rect(rect);
+            sort_rect(rect, &temp);
+            draw_rect(rect, _colorTable[32747]);
+        }
+    }
+
+    erase_rect(rect);
+    gameMouseSetCursor(MOUSE_CURSOR_ARROW);
+    gameMouseObjectsShow();
+}
+
 // 0x484294
 void sort_rect(Rect* a, Rect* b)
 {
diff --git a/src/mapper/map_func.h b/src/mapper/map_func.h
index 843f72a..71517e9 100644
--- a/src/mapper/map_func.h
+++ b/src/mapper/map_func.h
@@ -7,8 +7,9 @@ namespace fallout {
 
 void setup_map_dirs();
 void copy_proto_lists();
+void pick_region(Rect* rect);
 void sort_rect(Rect* a, Rect* b);
-void draw_rect(Rect* rect);
+void draw_rect(Rect* rect, unsigned char color);
 void erase_rect(Rect* rect);
 int toolbar_proto(int type, int id);
 bool map_toggle_block_obj_viewing_on();