(svn r20457) -Codechange: Remove _scrolling_scrollbar and WF_SCROLL_MIDDLE and instead store the widget index of the being scrolled scrollbar in the Window.

3 files changed, 21 insertions, 35 deletions

diff --git a/src/widget.cpp b/src/widget.cpp
index 88878e0c8..7c6447d0a 100644
--- a/src/widget.cpp
+++ b/src/widget.cpp
@@ -65,25 +65,24 @@ static Point HandleScrollbarHittest(const Scrollbar *sb, int top, int bottom, bo
 /**
  * Compute new position of the scrollbar after a click and updates the window flags.
  * @param w   Window on which a scroll was performed.
- * @param wtp Scrollbar widget type.
+ * @param nw  Scrollbar
  * @param mi  Minimum coordinate of the scroll bar.
  * @param ma  Maximum coordinate of the scroll bar.
  * @param x   The X coordinate of the mouse click.
  * @param y   The Y coordinate of the mouse click.
  */
-static void ScrollbarClickPositioning(Window *w, WidgetType wtp, int x, int y, int mi, int ma)
+static void ScrollbarClickPositioning(Window *w, NWidgetScrollbar *nw, int x, int y, int mi, int ma)
 {
 	int pos;
-	Scrollbar *sb;
 	bool rtl = false;
+	Scrollbar *sb = nw->GetScrollbar(w);
 
-	switch (wtp) {
+	switch (nw->type) {
 		case WWT_SCROLLBAR:
 			/* vertical scroller */
 			w->flags4 &= ~WF_HSCROLL;
 			w->flags4 &= ~WF_SCROLL2;
 			pos = y;
-			sb = &w->old_vscroll;
 			break;
 
 		case WWT_SCROLL2BAR:
@@ -91,7 +90,6 @@ static void ScrollbarClickPositioning(Window *w, WidgetType wtp, int x, int y, i
 			w->flags4 &= ~WF_HSCROLL;
 			w->flags4 |= WF_SCROLL2;
 			pos = y;
-			sb = &w->old_vscroll2;
 			break;
 
 		case WWT_HSCROLLBAR:
@@ -99,7 +97,6 @@ static void ScrollbarClickPositioning(Window *w, WidgetType wtp, int x, int y, i
 			w->flags4 &= ~WF_SCROLL2;
 			w->flags4 |= WF_HSCROLL;
 			pos = x;
-			sb = &w->old_hscroll;
 			rtl = _dynlang.text_dir == TD_RTL;
 			break;
 
@@ -123,7 +120,7 @@ static void ScrollbarClickPositioning(Window *w, WidgetType wtp, int x, int y, i
 		}
 		_left_button_clicked = false;
 	} else {
-		Point pt = HandleScrollbarHittest(sb, mi, ma, wtp == WWT_HSCROLLBAR);
+		Point pt = HandleScrollbarHittest(sb, mi, ma, nw->type == WWT_HSCROLLBAR);
 
 		if (pos < pt.x) {
 			sb->UpdatePosition(rtl ? sb->GetCapacity() : -sb->GetCapacity());
@@ -132,8 +129,7 @@ static void ScrollbarClickPositioning(Window *w, WidgetType wtp, int x, int y, i
 		} else {
 			_scrollbar_start_pos = pt.x - mi - 9;
 			_scrollbar_size = ma - mi - 23;
-			w->flags4 |= WF_SCROLL_MIDDLE;
-			_scrolling_scrollbar = true;
+			w->scrolling_scrollbar = nw->index;
 			_cursorpos_drag_start = _cursor.pos;
 		}
 	}
@@ -149,7 +145,7 @@ static void ScrollbarClickPositioning(Window *w, WidgetType wtp, int x, int y, i
  * @param x The X coordinate of the mouse click.
  * @param y The Y coordinate of the mouse click.
  */
-void ScrollbarClickHandler(Window *w, const NWidgetCore *nw, int x, int y)
+void ScrollbarClickHandler(Window *w, NWidgetCore *nw, int x, int y)
 {
 	int mi, ma;
 
@@ -174,7 +170,7 @@ void ScrollbarClickHandler(Window *w, const NWidgetCore *nw, int x, int y)
 
 		default: NOT_REACHED();
 	}
-	ScrollbarClickPositioning(w, nw->type, x, y, mi, ma);
+	ScrollbarClickPositioning(w, dynamic_cast<NWidgetScrollbar*>(nw), x, y, mi, ma);
 }
 
 /**
@@ -1693,21 +1689,21 @@ void NWidgetScrollbar::Draw(const Window *w)
 	switch (this->type) {
 		case WWT_HSCROLLBAR:
 			DrawHorizontalScrollbar(r, this->colour, (w->flags4 & (WF_SCROLL_UP | WF_HSCROLL)) == (WF_SCROLL_UP | WF_HSCROLL),
-								(w->flags4 & (WF_SCROLL_MIDDLE | WF_HSCROLL)) == (WF_SCROLL_MIDDLE | WF_HSCROLL),
+								w->scrolling_scrollbar == this->index,
 								(w->flags4 & (WF_SCROLL_DOWN | WF_HSCROLL)) == (WF_SCROLL_DOWN | WF_HSCROLL), this->GetScrollbar(w));
 			break;
 
 		case WWT_SCROLLBAR:
 			assert(this->widget_data == 0);
 			DrawVerticalScrollbar(r, this->colour, (w->flags4 & (WF_SCROLL_UP | WF_HSCROLL | WF_SCROLL2)) == WF_SCROLL_UP,
-								(w->flags4 & (WF_SCROLL_MIDDLE | WF_HSCROLL | WF_SCROLL2)) == WF_SCROLL_MIDDLE,
+								w->scrolling_scrollbar == this->index,
 								(w->flags4 & (WF_SCROLL_DOWN | WF_HSCROLL | WF_SCROLL2)) == WF_SCROLL_DOWN, this->GetScrollbar(w));
 			break;
 
 		case WWT_SCROLL2BAR:
 			assert(this->widget_data == 0);
 			DrawVerticalScrollbar(r, this->colour, (w->flags4 & (WF_SCROLL_UP | WF_HSCROLL | WF_SCROLL2)) == (WF_SCROLL_UP | WF_SCROLL2),
-								(w->flags4 & (WF_SCROLL_MIDDLE | WF_HSCROLL | WF_SCROLL2)) == (WF_SCROLL_MIDDLE | WF_SCROLL2),
+								w->scrolling_scrollbar == this->index,
 								(w->flags4 & (WF_SCROLL_DOWN | WF_HSCROLL | WF_SCROLL2)) == (WF_SCROLL_DOWN | WF_SCROLL2), this->GetScrollbar(w));
 			break;
 
diff --git a/src/window.cpp b/src/window.cpp
index cba0f799e..3919bf674 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -56,7 +56,6 @@ int _scrollbar_start_pos;
 int _scrollbar_size;
 byte _scroller_click_timeout;
 
-bool _scrolling_scrollbar; ///< A scrollbar is being scrolled with the mouse.
 bool _scrolling_viewport;  ///< A viewport is being scrolled with the mouse.
 bool _mouse_hovering;      ///< The mouse is hovering over the same point.
 
@@ -312,7 +311,7 @@ static void StartWindowSizing(Window *w, bool to_left);
  */
 static void DispatchLeftClickEvent(Window *w, int x, int y, int click_count)
 {
-	const NWidgetCore *nw = w->nested_root->GetWidgetFromPos(x, y);
+	NWidgetCore *nw = w->nested_root->GetWidgetFromPos(x, y);
 	WidgetType widget_type = (nw != NULL) ? nw->type : WWT_EMPTY;
 
 	bool focused_widget_changed = false;
@@ -1337,7 +1336,7 @@ void Window::InitNested(const WindowDesc *desc, WindowNumber window_number)
 }
 
 /** Empty constructor, initialization has been moved to #InitNested() called from the constructor of the derived class. */
-Window::Window() : old_hscroll(false), old_vscroll(true), old_vscroll2(true)
+Window::Window() : old_hscroll(false), old_vscroll(true), old_vscroll2(true), scrolling_scrollbar(-1)
 {
 }
 
@@ -1854,33 +1853,25 @@ static void StartWindowSizing(Window *w, bool to_left)
 static EventState HandleScrollbarScrolling()
 {
 	Window *w;
-
-	/* Get out quickly if no item is being scrolled */
-	if (!_scrolling_scrollbar) return ES_NOT_HANDLED;
-
-	/* Find the scrolling window */
 	FOR_ALL_WINDOWS_FROM_BACK(w) {
-		if (w->flags4 & WF_SCROLL_MIDDLE) {
+		if (w->scrolling_scrollbar >= 0) {
 			/* Abort if no button is clicked any more. */
 			if (!_left_button_down) {
-				w->flags4 &= ~WF_SCROLL_MIDDLE;
+				w->scrolling_scrollbar = -1;
 				w->SetDirty();
-				break;
+				return ES_HANDLED;
 			}
 
 			int i;
-			Scrollbar *sb;
+			Scrollbar *sb = w->GetScrollbar(w->scrolling_scrollbar);
 			bool rtl = false;
 
 			if (w->flags4 & WF_HSCROLL) {
-				sb = &w->old_hscroll;
 				i = _cursor.pos.x - _cursorpos_drag_start.x;
 				rtl = _dynlang.text_dir == TD_RTL;
 			} else if (w->flags4 & WF_SCROLL2) {
-				sb = &w->old_vscroll2;
 				i = _cursor.pos.y - _cursorpos_drag_start.y;
 			} else {
-				sb = &w->old_vscroll;
 				i = _cursor.pos.y - _cursorpos_drag_start.y;
 			}
 
@@ -1895,8 +1886,7 @@ static EventState HandleScrollbarScrolling()
 		}
 	}
 
-	_scrolling_scrollbar = false;
-	return ES_HANDLED;
+	return ES_NOT_HANDLED;
 }
 
 /**
diff --git a/src/window_gui.h b/src/window_gui.h
index 1f51c3aa5..9c7192399 100644
--- a/src/window_gui.h
+++ b/src/window_gui.h
@@ -398,6 +398,8 @@ public:
 	NWidgetStacked *shade_select;    ///< Selection widget (#NWID_SELECTION) to use for shading the window. If \c NULL, window cannot shade.
 	Dimension unshaded_size;         ///< Last known unshaded size (only valid while shaded).
 
+	int scrolling_scrollbar;         ///< Widgetindex of just being dragged scrollbar. -1 of none is active.
+
 	Window *parent;                  ///< Parent window.
 	Window *z_front;                 ///< The window in front of us in z-order.
 	Window *z_back;                  ///< The window behind us in z-order.
@@ -875,7 +877,6 @@ enum WindowFlags {
 	WF_DRAGGING          = 1 <<  3, ///< Window is being dragged
 	WF_SCROLL_UP         = 1 <<  4, ///< Upper scroll button has been pressed, @see ScrollbarClickHandler()
 	WF_SCROLL_DOWN       = 1 <<  5, ///< Lower scroll button has been pressed, @see ScrollbarClickHandler()
-	WF_SCROLL_MIDDLE     = 1 <<  6, ///< Scrollbar scrolling, @see ScrollbarClickHandler()
 	WF_SCROLL2           = 1 <<  7,
 	WF_HSCROLL           = 1 <<  8,
 	WF_SIZING_RIGHT      = 1 <<  9, ///< Window is being resized towards the right.
@@ -933,7 +934,6 @@ extern int _scrollbar_start_pos;
 extern int _scrollbar_size;
 extern byte _scroller_click_timeout;
 
-extern bool _scrolling_scrollbar;
 extern bool _scrolling_viewport;
 extern bool _mouse_hovering;
 
@@ -951,6 +951,6 @@ Window *GetCallbackWnd();
 void SetFocusedWindow(Window *w);
 bool EditBoxInGlobalFocus();
 
-void ScrollbarClickHandler(Window *w, const NWidgetCore *nw, int x, int y);
+void ScrollbarClickHandler(Window *w, NWidgetCore *nw, int x, int y);
 
 #endif /* WINDOW_GUI_H */