Wheel scrolling

src/backup/todo.txt

@@ -2,7 +2,6 @@
 ! From a user (novice) point of view, how does it look like?
 
 - Make a fuzzy command !> grep and fuzzy over it??? (doesn't seem very useful for grep)
-- Maybe wheel click should scroll??? PROBABLY
 
 - Make all the keybinding / hook parsing initialize at the start to reduce runtime problems
 - RegisterCommand should_appear_in_listing variable

src/text_editor/globals.cpp

@@ -44,6 +44,7 @@ WindowID DocumentSelected  = {-1};
 WindowID ResizerSelected = {-1};
 WindowID ResizerHover = {-1};
 Caret    DocumentAnchor;
+Vec2I    MouseMiddleAnchor;
 
 Buffer *GCInfoBuffer;
 Buffer *EventBuffer;

src/text_editor/text_editor.cpp

@@ -58,6 +58,8 @@ void SetMouseCursor(SDL_SystemCursor id) {
         JS_SetMouseCursor("default");
     } else if (id == SDL_SYSTEM_CURSOR_TEXT) {
         JS_SetMouseCursor("text");
+    } else if (id == SDL_SYSTEM_CURSOR_MOVE) {
+        JS_SetMouseCursor("all-scroll");
     } else {
         InvalidCodepath();
     }
@@ -104,6 +106,11 @@ void SetMouseCursor(Event event) {
         return;
     }
 
+    if (MouseMiddleAnchor.x != 0 && MouseMiddleAnchor.y != 0) {
+        SetMouseCursor(SDL_SYSTEM_CURSOR_MOVE);
+        return;
+    }
+
     For(order) {
         if (!it->visible) continue;
         bool mouse_in_total     = AreOverlapping(mouse, it->total_rect);
@@ -315,6 +322,20 @@ void OnCommand(Event event) {
         MouseLoadWord(event);
     }
 
+    {
+        Vec2I mouse = MouseVec2I();
+        if (Mouse(MIDDLE)) {
+            MouseMiddleAnchor = mouse;
+        } else if (Mouse(MIDDLE_UP)) {
+            MouseMiddleAnchor = {0, 0};
+        }
+        if (MouseMiddleAnchor.x != 0) {
+            BSet active = GetBSet(ActiveWindowID);
+            active.view->scroll += mouse - MouseMiddleAnchor;
+        }
+    }
+
+
     if (Ctrl() && Mouse(LEFT)) {
         MouseLoadWord(event);
     } else if (Mouse(LEFT)) { // Uses Alt and shift