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Codechange: Replace window related FOR_ALL with range-based for loops

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This commit is contained in:
glx22 2021-04-28 21:24:24 +02:00 committed by Loïc Guilloux
parent a61696d6c5
commit 14e92bd8e2
6 changed files with 113 additions and 106 deletions
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3
src/misc_gui.cpp
View File

@ -1284,8 +1284,7 @@ void ShowQuery(StringID caption, StringID message, Window *parent, QueryCallback
{
if (parent == nullptr) parent = FindWindowById(WC_MAIN_WINDOW, 0);
const Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class != WC_CONFIRM_POPUP_QUERY) continue;
const QueryWindow *qw = (const QueryWindow *)w;

3
src/sound.cpp
View File

@ -238,8 +238,7 @@ static void SndPlayScreenCoordFx(SoundID sound, int left, int right, int top, in
{
if (_settings_client.music.effect_vol == 0) return;
const Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
const Viewport *vp = w->viewport;
if (vp != nullptr &&

11
src/viewport.cpp
View File

@ -268,7 +268,7 @@ static Point _vp_move_offs;
static void DoSetViewportPosition(const Window *w, int left, int top, int width, int height)
{
FOR_ALL_WINDOWS_FROM_BACK_FROM(w, w) {
for (const Window *w : Window::IterateFromBack(w)) {
if (left + width > w->left &&
w->left + w->width > left &&
top + height > w->top &&
@ -1475,8 +1475,7 @@ void ViewportSign::MarkDirty(ZoomLevel maxzoom) const
zoomlevels[zoom].bottom = this->top + ScaleByZoom(VPSM_TOP + FONT_HEIGHT_NORMAL + VPSM_BOTTOM + 1, zoom);
}
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
Viewport *vp = w->viewport;
if (vp != nullptr && vp->zoom <= maxzoom) {
assert(vp->width != 0);
@ -1949,8 +1948,7 @@ bool MarkAllViewportsDirty(int left, int top, int right, int bottom)
{
bool dirty = false;
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
Viewport *vp = w->viewport;
if (vp != nullptr) {
assert(vp->width != 0);
@ -1963,8 +1961,7 @@ bool MarkAllViewportsDirty(int left, int top, int right, int bottom)
void ConstrainAllViewportsZoom()
{
Window *w;
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
if (w->viewport == nullptr) continue;
ZoomLevel zoom = static_cast<ZoomLevel>(Clamp(w->viewport->zoom, _settings_client.gui.zoom_min, _settings_client.gui.zoom_max));

3
src/widgets/dropdown.cpp
View File

@ -505,8 +505,7 @@ void ShowDropDownMenu(Window *w, const StringID *strings, int selected, int butt
*/
int HideDropDownMenu(Window *pw)
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->window_class != WC_DROPDOWN_MENU) continue;
DropdownWindow *dw = dynamic_cast<DropdownWindow*>(w);

131
src/window.cpp
View File

@ -898,8 +898,7 @@ static bool MayBeShown(const Window *w)
*/
static void DrawOverlappedWindow(Window *w, int left, int top, int right, int bottom)
{
const Window *v;
FOR_ALL_WINDOWS_FROM_BACK_FROM(v, w->z_front) {
for (const Window *v : Window::IterateFromBack(w->z_front)) {
if (MayBeShown(v) &&
right > v->left &&
bottom > v->top &&
@ -958,13 +957,11 @@ static void DrawOverlappedWindow(Window *w, int left, int top, int right, int bo
*/
void DrawOverlappedWindowForAll(int left, int top, int right, int bottom)
{
Window *w;
DrawPixelInfo *old_dpi = _cur_dpi;
DrawPixelInfo bk;
_cur_dpi = &bk;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (MayBeShown(w) &&
right > w->left &&
bottom > w->top &&
@ -1057,8 +1054,7 @@ void Window::SetShaded(bool make_shaded)
*/
static Window *FindChildWindow(const Window *w, WindowClass wc)
{
Window *v;
FOR_ALL_WINDOWS_FROM_BACK(v) {
for (Window *v : Window::IterateFromBack()) {
if ((wc == WC_INVALID || wc == v->window_class) && v->parent == w) return v;
}
@ -1132,8 +1128,7 @@ Window::~Window()
*/
Window *FindWindowById(WindowClass cls, WindowNumber number)
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->window_class == cls && w->window_number == number) return w;
}
@ -1148,8 +1143,7 @@ Window *FindWindowById(WindowClass cls, WindowNumber number)
*/
Window *FindWindowByClass(WindowClass cls)
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->window_class == cls) return w;
}
@ -1176,13 +1170,11 @@ void DeleteWindowById(WindowClass cls, WindowNumber number, bool force)
*/
void DeleteWindowByClass(WindowClass cls)
{
Window *w;
restart_search:
/* When we find the window to delete, we need to restart the search
* as deleting this window could cascade in deleting (many) others
* anywhere in the z-array */
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->window_class == cls) {
delete w;
goto restart_search;
@ -1198,13 +1190,11 @@ restart_search:
*/
void DeleteCompanyWindows(CompanyID id)
{
Window *w;
restart_search:
/* When we find the window to delete, we need to restart the search
* as deleting this window could cascade in deleting (many) others
* anywhere in the z-array */
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->owner == id) {
delete w;
goto restart_search;
@ -1224,8 +1214,7 @@ restart_search:
*/
void ChangeWindowOwner(Owner old_owner, Owner new_owner)
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->owner != old_owner) continue;
switch (w->window_class) {
@ -1594,8 +1583,7 @@ static bool IsGoodAutoPlace1(int left, int top, int width, int height, int toolb
if (left < 0 || top < toolbar_y || right > _screen.width || bottom > _screen.height) return false;
/* Make sure it is not obscured by any window. */
const Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class == WC_MAIN_WINDOW) continue;
if (right > w->left &&
@ -1640,8 +1628,7 @@ static bool IsGoodAutoPlace2(int left, int top, int width, int height, int toolb
if (top < toolbar_y || top > _screen.height - (height >> 2)) return false;
/* Make sure it is not obscured by any window. */
const Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class == WC_MAIN_WINDOW) continue;
if (left + width > w->left &&
@ -1678,8 +1665,7 @@ static Point GetAutoPlacePosition(int width, int height)
* The new window must be entirely on-screen, and not overlap with an existing window.
* Eight starting points are tried, two at each corner.
*/
const Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class == WC_MAIN_WINDOW) continue;
if (IsGoodAutoPlace1(w->left + w->width, w->top, width, height, toolbar_y, pt)) return pt;
@ -1696,7 +1682,7 @@ static Point GetAutoPlacePosition(int width, int height)
* The new window may be partly off-screen, and must not overlap with an existing window.
* Only four starting points are tried.
*/
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class == WC_MAIN_WINDOW) continue;
if (IsGoodAutoPlace2(w->left + w->width, w->top, width, height, toolbar_y, pt)) return pt;
@ -1713,7 +1699,7 @@ static Point GetAutoPlacePosition(int width, int height)
int offset_y = std::max<int>(NWidgetLeaf::closebox_dimension.height, FONT_HEIGHT_NORMAL + WD_CAPTIONTEXT_TOP + WD_CAPTIONTEXT_BOTTOM);
restart:
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->left == left && w->top == top) {
left += offset_x;
top += offset_y;
@ -1880,8 +1866,7 @@ Window::Window(WindowDesc *desc) : window_desc(desc), mouse_capture_widget(-1)
*/
Window *FindWindowFromPt(int x, int y)
{
Window *w;
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
if (MayBeShown(w) && IsInsideBS(x, w->left, w->width) && IsInsideBS(y, w->top, w->height)) {
return w;
}
@ -1918,10 +1903,9 @@ void UnInitWindowSystem()
{
UnshowCriticalError();
Window *w;
FOR_ALL_WINDOWS_FROM_FRONT(w) delete w;
for (Window *w : Window::IterateFromFront()) delete w;
for (w = _z_front_window; w != nullptr; /* nothing */) {
for (Window *w = _z_front_window; w != nullptr; /* nothing */) {
Window *to_del = w;
w = w->z_back;
free(to_del);
@ -1948,8 +1932,7 @@ static void DecreaseWindowCounters()
if (_scroller_click_timeout != 0) _scroller_click_timeout--;
if (hundredth_tick_timeout != 0) hundredth_tick_timeout--;
Window *w;
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
if (!_network_dedicated && hundredth_tick_timeout == 0) w->OnHundredthTick();
if (_scroller_click_timeout == 0) {
@ -1975,7 +1958,7 @@ static void DecreaseWindowCounters()
w->OnMouseLoop();
}
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
if ((w->flags & WF_TIMEOUT) && --w->timeout_timer == 0) {
CLRBITS(w->flags, WF_TIMEOUT);
@ -2217,8 +2200,7 @@ static EventState HandleWindowDragging()
if (_left_button_down && _cursor.delta.x == 0 && _cursor.delta.y == 0) return ES_HANDLED;
/* Otherwise find the window... */
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->flags & WF_DRAGGING) {
/* Stop the dragging if the left mouse button was released */
if (!_left_button_down) {
@ -2234,13 +2216,11 @@ static EventState HandleWindowDragging()
int ny = y;
if (_settings_client.gui.window_snap_radius != 0) {
const Window *v;
int hsnap = _settings_client.gui.window_snap_radius;
int vsnap = _settings_client.gui.window_snap_radius;
int delta;
FOR_ALL_WINDOWS_FROM_BACK(v) {
for (const Window *v : Window::IterateFromBack()) {
if (v == w) continue; // Don't snap at yourself
if (y + w->height > v->top && y < v->top + v->height) {
@ -2454,8 +2434,7 @@ static void HandleScrollbarScrolling(Window *w)
*/
static EventState HandleActiveWidget()
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->mouse_capture_widget >= 0) {
/* Abort if no button is clicked any more. */
if (!_left_button_down) {
@ -2565,8 +2544,7 @@ static bool MaybeBringWindowToFront(Window *w)
w_height = w->unshaded_size.height;
}
Window *u;
FOR_ALL_WINDOWS_FROM_BACK_FROM(u, w->z_front) {
for (Window *u : Window::IterateFromBack(w->z_front)) {
/* A modal child will prevent the activation of the parent window */
if (u->parent == w && (u->window_desc->flags & WDF_MODAL)) {
u->SetWhiteBorder();
@ -2708,8 +2686,7 @@ void HandleKeypress(uint keycode, WChar key)
}
/* Call the event, start with the uppermost window, but ignore the toolbar. */
Window *w;
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
if (w->window_class == WC_MAIN_TOOLBAR) continue;
if (w->window_desc->hotkeys != nullptr) {
int hotkey = w->window_desc->hotkeys->CheckMatch(keycode);
@ -2718,7 +2695,7 @@ void HandleKeypress(uint keycode, WChar key)
if (w->OnKeyPress(key, keycode) == ES_HANDLED) return;
}
w = FindWindowById(WC_MAIN_TOOLBAR, 0);
Window *w = FindWindowById(WC_MAIN_TOOLBAR, 0);
/* When there is no toolbar w is null, check for that */
if (w != nullptr) {
if (w->window_desc->hotkeys != nullptr) {
@ -2737,8 +2714,7 @@ void HandleKeypress(uint keycode, WChar key)
void HandleCtrlChanged()
{
/* Call the event, start with the uppermost window. */
Window *w;
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
if (w->OnCTRLStateChange() == ES_HANDLED) return;
}
}
@ -3073,8 +3049,8 @@ static void CheckSoftLimit()
for (;;) {
uint deletable_count = 0;
Window *w, *last_deletable = nullptr;
FOR_ALL_WINDOWS_FROM_FRONT(w) {
Window *last_deletable = nullptr;
for (Window *w : Window::IterateFromFront()) {
if (w->window_class == WC_MAIN_WINDOW || IsVitalWindow(w) || (w->flags & WF_STICKY)) continue;
last_deletable = w;
@ -3127,8 +3103,7 @@ void InputLoop()
*/
void CallWindowRealtimeTickEvent(uint delta_ms)
{
Window *w;
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
w->OnRealtimeTick(delta_ms);
}
}
@ -3156,10 +3131,8 @@ void UpdateWindows()
NetworkChatMessageLoop();
}
Window *w;
/* Process invalidations before anything else. */
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
w->ProcessScheduledInvalidations();
w->ProcessHighlightedInvalidations();
}
@ -3192,7 +3165,7 @@ void UpdateWindows()
if (window_timer.HasElapsed()) {
window_timer.SetInterval(MILLISECONDS_PER_TICK);
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
if ((w->flags & WF_WHITE_BORDER) && --w->white_border_timer == 0) {
CLRBITS(w->flags, WF_WHITE_BORDER);
w->SetDirty();
@ -3202,7 +3175,7 @@ void UpdateWindows()
DrawDirtyBlocks();
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
/* Update viewport only if window is not shaded. */
if (w->viewport != nullptr && !w->IsShaded()) UpdateViewportPosition(w);
}
@ -3218,8 +3191,7 @@ void UpdateWindows()
*/
void SetWindowDirty(WindowClass cls, WindowNumber number)
{
const Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class == cls && w->window_number == number) w->SetDirty();
}
}
@ -3232,8 +3204,7 @@ void SetWindowDirty(WindowClass cls, WindowNumber number)
*/
void SetWindowWidgetDirty(WindowClass cls, WindowNumber number, byte widget_index)
{
const Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class == cls && w->window_number == number) {
w->SetWidgetDirty(widget_index);
}
@ -3246,8 +3217,7 @@ void SetWindowWidgetDirty(WindowClass cls, WindowNumber number, byte widget_inde
*/
void SetWindowClassesDirty(WindowClass cls)
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class == cls) w->SetDirty();
}
}
@ -3319,8 +3289,7 @@ void Window::ProcessHighlightedInvalidations()
*/
void InvalidateWindowData(WindowClass cls, WindowNumber number, int data, bool gui_scope)
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->window_class == cls && w->window_number == number) {
w->InvalidateData(data, gui_scope);
}
@ -3337,9 +3306,7 @@ void InvalidateWindowData(WindowClass cls, WindowNumber number, int data, bool g
*/
void InvalidateWindowClassesData(WindowClass cls, int data, bool gui_scope)
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
if (w->window_class == cls) {
w->InvalidateData(data, gui_scope);
}
@ -3351,8 +3318,7 @@ void InvalidateWindowClassesData(WindowClass cls, int data, bool gui_scope)
*/
void CallWindowGameTickEvent()
{
Window *w;
FOR_ALL_WINDOWS_FROM_FRONT(w) {
for (Window *w : Window::IterateFromFront()) {
w->OnGameTick();
}
}
@ -3365,13 +3331,11 @@ void CallWindowGameTickEvent()
*/
void DeleteNonVitalWindows()
{
Window *w;
restart_search:
/* When we find the window to delete, we need to restart the search
* as deleting this window could cascade in deleting (many) others
* anywhere in the z-array */
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_class != WC_MAIN_WINDOW &&
w->window_class != WC_SELECT_GAME &&
w->window_class != WC_MAIN_TOOLBAR &&
@ -3394,8 +3358,6 @@ restart_search:
*/
void DeleteAllNonVitalWindows()
{
Window *w;
/* Delete every window except for stickied ones, then sticky ones as well */
DeleteNonVitalWindows();
@ -3403,7 +3365,7 @@ restart_search:
/* When we find the window to delete, we need to restart the search
* as deleting this window could cascade in deleting (many) others
* anywhere in the z-array */
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->flags & WF_STICKY) {
delete w;
goto restart_search;
@ -3428,20 +3390,18 @@ void DeleteAllMessages()
*/
void DeleteConstructionWindows()
{
Window *w;
restart_search:
/* When we find the window to delete, we need to restart the search
* as deleting this window could cascade in deleting (many) others
* anywhere in the z-array */
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->window_desc->flags & WDF_CONSTRUCTION) {
delete w;
goto restart_search;
}
}
FOR_ALL_WINDOWS_FROM_BACK(w) w->SetDirty();
for (const Window *w : Window::IterateFromBack()) w->SetDirty();
}
/** Delete all always on-top windows to get an empty screen */
@ -3460,8 +3420,7 @@ void ReInitAllWindows()
extern void InitDepotWindowBlockSizes();
InitDepotWindowBlockSizes();
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
w->ReInit();
}
@ -3550,8 +3509,7 @@ int PositionNetworkChatWindow(Window *w)
*/
void ChangeVehicleViewports(VehicleID from_index, VehicleID to_index)
{
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (const Window *w : Window::IterateFromBack()) {
if (w->viewport != nullptr && w->viewport->follow_vehicle == from_index) {
w->viewport->follow_vehicle = to_index;
w->SetDirty();
@ -3569,8 +3527,7 @@ void RelocateAllWindows(int neww, int newh)
{
DeleteWindowById(WC_DROPDOWN_MENU, 0);
Window *w;
FOR_ALL_WINDOWS_FROM_BACK(w) {
for (Window *w : Window::IterateFromBack()) {
int left, top;
/* XXX - this probably needs something more sane. For example specifying
* in a 'backup'-desc that the window should always be centered. */

68
src/window_gui.h
View File

@ -810,6 +810,68 @@ public:
* @pre this->IsNewGRFInspectable()
*/
virtual void ShowNewGRFInspectWindow() const { NOT_REACHED(); }
/**
* Iterator to iterate all valid Windows
* @tparam T Type of the class/struct that is going to be iterated
* @tparam Tfront Wether we iterate from front
*/
template <class T, bool Tfront>
struct WindowIterator {
typedef T value_type;
typedef T *pointer;
typedef T &reference;
typedef size_t difference_type;
typedef std::forward_iterator_tag iterator_category;
explicit WindowIterator(T *start) : w(start)
{
this->Validate();
}
bool operator==(const WindowIterator &other) const { return this->w == other.w; }
bool operator!=(const WindowIterator &other) const { return !(*this == other); }
T * operator*() const { return this->w; }
WindowIterator & operator++() { this->Next(); this->Validate(); return *this; }
private:
T *w;
void Validate() { while (this->w != nullptr && this->w->window_class == WC_INVALID) this->Next(); }
void Next() { if (this->w != nullptr) this->w = Tfront ? this->w->z_back : this->w->z_front; }
};
/**
* Iterable ensemble of all valid Windows
* @tparam T Type of the class/struct that is going to be iterated
* @tparam Tfront Wether we iterate from front
*/
template <class T, bool Tfront>
struct Iterate {
Iterate(T *from) : from(from) {}
WindowIterator<T, Tfront> begin() { return WindowIterator<T, Tfront>(this->from); }
WindowIterator<T, Tfront> end() { return WindowIterator<T, Tfront>(nullptr); }
bool empty() { return this->begin() == this->end(); }
private:
T *from;
};
/**
* Returns an iterable ensemble of all valid Window from back to front
* @tparam T Type of the class/struct that is going to be iterated
* @param from index of the first Window to consider
* @return an iterable ensemble of all valid Window
*/
template <class T = Window>
static Iterate<T, false> IterateFromBack(T *from = _z_back_window) { return Iterate<T, false>(from); }
/**
* Returns an iterable ensemble of all valid Window from front to back
* @tparam T Type of the class/struct that is going to be iterated
* @param from index of the first Window to consider
* @return an iterable ensemble of all valid Window
*/
template <class T = Window>
static Iterate<T, true> IterateFromFront(T *from = _z_front_window) { return Iterate<T, true>(from); }
};
/**
@ -888,12 +950,6 @@ void GuiShowTooltips(Window *parent, StringID str, uint paramcount = 0, const ui
/* widget.cpp */
int GetWidgetFromPos(const Window *w, int x, int y);
/** Iterate over all windows */
#define FOR_ALL_WINDOWS_FROM_BACK_FROM(w, start) for (w = start; w != nullptr; w = w->z_front) if (w->window_class != WC_INVALID)
#define FOR_ALL_WINDOWS_FROM_FRONT_FROM(w, start) for (w = start; w != nullptr; w = w->z_back) if (w->window_class != WC_INVALID)
#define FOR_ALL_WINDOWS_FROM_BACK(w) FOR_ALL_WINDOWS_FROM_BACK_FROM(w, _z_back_window)
#define FOR_ALL_WINDOWS_FROM_FRONT(w) FOR_ALL_WINDOWS_FROM_FRONT_FROM(w, _z_front_window)
extern Point _cursorpos_drag_start;
extern int _scrollbar_start_pos;