Fix: Recalculate padding and minimum sizes when GUI or Font zoom is changed.

13 files changed, 129 insertions, 28 deletions

diff --git a/src/gfx.cpp b/src/gfx.cpp
index d3c730be1..1f4b40a54 100644
--- a/src/gfx.cpp
+++ b/src/gfx.cpp
@@ -1285,7 +1285,7 @@ void LoadStringWidthTable(bool monospace)
 		}
 	}
 
-	ReInitAllWindows();
+	ReInitAllWindows(false);
 }
 
 /**
diff --git a/src/gfxinit.cpp b/src/gfxinit.cpp
index 7e2c2cc62..b744eaa5e 100644
--- a/src/gfxinit.cpp
+++ b/src/gfxinit.cpp
@@ -323,7 +323,7 @@ void CheckBlitter()
 
 	ClearFontCache();
 	GfxClearSpriteCache();
-	ReInitAllWindows();
+	ReInitAllWindows(false);
 }
 
 /** Initialise and load all the sprites. */
diff --git a/src/network/network_gui.cpp b/src/network/network_gui.cpp
index 590f2f5e0..b2feacc95 100644
--- a/src/network/network_gui.cpp
+++ b/src/network/network_gui.cpp
@@ -98,7 +98,9 @@ public:
 		this->Add(new NWidgetLeaf(WWT_PUSHTXTBTN, COLOUR_WHITE, WID_NG_YEARS, STR_NETWORK_SERVER_LIST_YEARS_CAPTION, STR_NETWORK_SERVER_LIST_YEARS_CAPTION_TOOLTIP));
 
 		leaf = new NWidgetLeaf(WWT_PUSHTXTBTN, COLOUR_WHITE, WID_NG_INFO, STR_EMPTY, STR_NETWORK_SERVER_LIST_INFO_ICONS_TOOLTIP);
-		leaf->SetMinimalSize(14 + GetSpriteSize(SPR_LOCK).width + GetSpriteSize(SPR_BLOT).width + GetSpriteSize(SPR_FLAGS_BASE).width, 12);
+		leaf->SetMinimalSize(14 + GetSpriteSize(SPR_LOCK, nullptr, ZOOM_LVL_OUT_4X).width
+		                        + GetSpriteSize(SPR_BLOT, nullptr, ZOOM_LVL_OUT_4X).width
+		                        + GetSpriteSize(SPR_FLAGS_BASE, nullptr, ZOOM_LVL_OUT_4X).width, 12);
 		leaf->SetFill(0, 1);
 		this->Add(leaf);
 
diff --git a/src/newgrf_gui.cpp b/src/newgrf_gui.cpp
index 3465a9437..6316a7c4b 100644
--- a/src/newgrf_gui.cpp
+++ b/src/newgrf_gui.cpp
@@ -1972,7 +1972,7 @@ static void NewGRFConfirmationCallback(Window *w, bool confirmed)
 
 		w->InvalidateData();
 
-		ReInitAllWindows();
+		ReInitAllWindows(false);
 		DeleteWindowByClass(WC_BUILD_OBJECT);
 	}
 }
diff --git a/src/osk_gui.cpp b/src/osk_gui.cpp
index 233bb1c7a..119f26eae 100644
--- a/src/osk_gui.cpp
+++ b/src/osk_gui.cpp
@@ -237,7 +237,7 @@ static void AddKey(NWidgetHorizontal *hor, int height, int num_half, WidgetType
 			hor->Add(spc);
 		}
 		NWidgetLeaf *leaf = new NWidgetLeaf(widtype, COLOUR_GREY, widnum, widdata, STR_NULL);
-		leaf->SetMinimalSize(ScaleGUITrad(key_width), height);
+		leaf->SetMinimalSizeAbsolute(ScaleGUITrad(key_width), height);
 		hor->Add(leaf);
 	}
 
diff --git a/src/settings.cpp b/src/settings.cpp
index 9b97107a3..c5819297f 100644
--- a/src/settings.cpp
+++ b/src/settings.cpp
@@ -1172,7 +1172,7 @@ static bool InvalidateNewGRFChangeWindows(int32 p1)
 {
 	InvalidateWindowClassesData(WC_SAVELOAD);
 	DeleteWindowByClass(WC_GAME_OPTIONS);
-	ReInitAllWindows();
+	ReInitAllWindows(_gui_zoom_cfg);
 	return true;
 }
 
diff --git a/src/settings_gui.cpp b/src/settings_gui.cpp
index 52d900e6e..47524bcfb 100644
--- a/src/settings_gui.cpp
+++ b/src/settings_gui.cpp
@@ -530,7 +530,7 @@ struct GameOptionsWindow : Window {
 			case WID_GO_CURRENCY_DROPDOWN: // Currency
 				if (index == CURRENCY_CUSTOM) ShowCustCurrency();
 				this->opt->locale.currency = index;
-				ReInitAllWindows();
+				ReInitAllWindows(false);
 				break;
 
 			case WID_GO_AUTOSAVE_DROPDOWN: // Autosave options
@@ -545,7 +545,7 @@ struct GameOptionsWindow : Window {
 				ClearAllCachedNames();
 				UpdateAllVirtCoords();
 				CheckBlitter();
-				ReInitAllWindows();
+				ReInitAllWindows(false);
 				break;
 
 			case WID_GO_RESOLUTION_DROPDOWN: // Change resolution
@@ -573,7 +573,7 @@ struct GameOptionsWindow : Window {
 					UpdateCursorSize();
 					UpdateAllVirtCoords();
 					FixTitleGameZoom();
-					ReInitAllWindows();
+					ReInitAllWindows(true);
 				}
 				break;
 			}
@@ -587,6 +587,7 @@ struct GameOptionsWindow : Window {
 					ClearFontCache();
 					LoadStringWidthTable();
 					UpdateAllVirtCoords();
+					ReInitAllWindows(true);
 				}
 				break;
 			}
diff --git a/src/video/video_driver.cpp b/src/video/video_driver.cpp
index eaff0b741..d8fbe0400 100644
--- a/src/video/video_driver.cpp
+++ b/src/video/video_driver.cpp
@@ -115,7 +115,7 @@ void VideoDriver::RealChangeBlitter(const char *repl_blitter)
 	this->ClearSystemSprites();
 	ClearFontCache();
 	GfxClearSpriteCache();
-	ReInitAllWindows();
+	ReInitAllWindows(false);
 }
 
 void VideoDriver::Tick()
diff --git a/src/widget.cpp b/src/widget.cpp
index aae1a5165..68bc43d78 100644
--- a/src/widget.cpp
+++ b/src/widget.cpp
@@ -822,6 +822,14 @@ NWidgetBase *NWidgetBase::GetWidgetOfType(WidgetType tp)
 	return (this->type == tp) ? this : nullptr;
 }
 
+void NWidgetBase::AdjustPaddingForZoom()
+{
+	this->padding_top    = ScaleGUITrad(this->uz_padding_top);
+	this->padding_right  = ScaleGUITrad(this->uz_padding_right);
+	this->padding_bottom = ScaleGUITrad(this->uz_padding_bottom);
+	this->padding_left   = ScaleGUITrad(this->uz_padding_left);
+}
+
 /**
  * Constructor for resizable nested widgets.
  * @param tp     Nested widget type.
@@ -834,6 +842,15 @@ NWidgetResizeBase::NWidgetResizeBase(WidgetType tp, uint fill_x, uint fill_y) :
 	this->fill_y = fill_y;
 }
 
+void NWidgetResizeBase::AdjustPaddingForZoom()
+{
+	if (!this->absolute) {
+		this->min_x = ScaleGUITrad(this->uz_min_x);
+		this->min_y = std::max(ScaleGUITrad(this->uz_min_y), this->uz_text_lines * GetCharacterHeight(this->uz_text_size) + ScaleGUITrad(this->uz_text_spacing));
+	}
+	NWidgetBase::AdjustPaddingForZoom();
+}
+
 /**
  * Set minimal size of the widget.
  * @param min_x Horizontal minimal size of the widget.
@@ -841,6 +858,20 @@ NWidgetResizeBase::NWidgetResizeBase(WidgetType tp, uint fill_x, uint fill_y) :
  */
 void NWidgetResizeBase::SetMinimalSize(uint min_x, uint min_y)
 {
+	this->uz_min_x = std::max(this->uz_min_x, min_x);
+	this->uz_min_y = std::max(this->uz_min_y, min_y);
+	this->min_x = ScaleGUITrad(this->uz_min_x);
+	this->min_y = std::max(ScaleGUITrad(this->uz_min_y), this->uz_text_lines * GetCharacterHeight(this->uz_text_size) + ScaleGUITrad(this->uz_text_spacing));
+}
+
+/**
+ * Set absolute (post-scaling) minimal size of the widget.
+ * @param min_x Horizontal minimal size of the widget.
+ * @param min_y Vertical minimal size of the widget.
+ */
+void NWidgetResizeBase::SetMinimalSizeAbsolute(uint min_x, uint min_y)
+{
+	this->absolute = true;
 	this->min_x = std::max(this->min_x, min_x);
 	this->min_y = std::max(this->min_y, min_y);
 }
@@ -853,7 +884,10 @@ void NWidgetResizeBase::SetMinimalSize(uint min_x, uint min_y)
  */
 void NWidgetResizeBase::SetMinimalTextLines(uint8 min_lines, uint8 spacing, FontSize size)
 {
-	this->min_y = min_lines * GetCharacterHeight(size) + spacing;
+	this->uz_text_lines = min_lines;
+	this->uz_text_spacing = spacing;
+	this->uz_text_size = size;
+	this->min_y = std::max(ScaleGUITrad(this->uz_min_y), this->uz_text_lines * GetCharacterHeight(this->uz_text_size) + ScaleGUITrad(this->uz_text_spacing));
 }
 
 /**
@@ -991,6 +1025,14 @@ NWidgetBase *NWidgetContainer::GetWidgetOfType(WidgetType tp)
 	return nullptr;
 }
 
+void NWidgetContainer::AdjustPaddingForZoom()
+{
+	for (NWidgetBase *child_wid = this->head; child_wid != nullptr; child_wid = child_wid->next) {
+		child_wid->AdjustPaddingForZoom();
+	}
+	NWidgetBase::AdjustPaddingForZoom();
+}
+
 /**
  * Append widget \a wid to container.
  * @param wid Widget to append.
@@ -1032,6 +1074,14 @@ void NWidgetStacked::SetIndex(int index)
 	this->index = index;
 }
 
+void NWidgetStacked::AdjustPaddingForZoom()
+{
+	for (NWidgetBase *child_wid = this->head; child_wid != nullptr; child_wid = child_wid->next) {
+		child_wid->AdjustPaddingForZoom();
+	}
+	NWidgetContainer::AdjustPaddingForZoom();
+}
+
 void NWidgetStacked::SetupSmallestSize(Window *w, bool init_array)
 {
 	if (this->index >= 0 && init_array) { // Fill w->nested_array[]
@@ -1145,6 +1195,14 @@ NWidgetPIPContainer::NWidgetPIPContainer(WidgetType tp, NWidContainerFlags flags
 	this->flags = flags;
 }
 
+void NWidgetPIPContainer::AdjustPaddingForZoom()
+{
+	this->pip_pre = ScaleGUITrad(this->uz_pip_pre);
+	this->pip_inter = ScaleGUITrad(this->uz_pip_inter);
+	this->pip_post = ScaleGUITrad(this->uz_pip_post);
+	NWidgetContainer::AdjustPaddingForZoom();
+}
+
 /**
  * Set additional pre/inter/post space for the container.
  *
@@ -1156,9 +1214,13 @@ NWidgetPIPContainer::NWidgetPIPContainer(WidgetType tp, NWidContainerFlags flags
  */
 void NWidgetPIPContainer::SetPIP(uint8 pip_pre, uint8 pip_inter, uint8 pip_post)
 {
-	this->pip_pre = pip_pre;
-	this->pip_inter = pip_inter;
-	this->pip_post = pip_post;
+	this->uz_pip_pre = pip_pre;
+	this->uz_pip_inter = pip_inter;
+	this->uz_pip_post = pip_post;
+
+	this->pip_pre = ScaleGUITrad(this->uz_pip_pre);
+	this->pip_inter = ScaleGUITrad(this->uz_pip_inter);
+	this->pip_post = ScaleGUITrad(this->uz_pip_post);
 }
 
 void NWidgetPIPContainer::Draw(const Window *w)
@@ -1813,6 +1875,12 @@ void NWidgetBackground::SetPIP(uint8 pip_pre, uint8 pip_inter, uint8 pip_post)
 	this->child->SetPIP(pip_pre, pip_inter, pip_post);
 }
 
+void NWidgetBackground::AdjustPaddingForZoom()
+{
+	if (child != nullptr) child->AdjustPaddingForZoom();
+	NWidgetCore::AdjustPaddingForZoom();
+}
+
 void NWidgetBackground::SetupSmallestSize(Window *w, bool init_array)
 {
 	if (init_array && this->index >= 0) {
@@ -2137,11 +2205,11 @@ void NWidgetScrollbar::SetupSmallestSize(Window *w, bool init_array)
 
 	switch (this->type) {
 		case NWID_HSCROLLBAR:
-			this->SetMinimalSize(NWidgetScrollbar::GetHorizontalDimension().width * 3, NWidgetScrollbar::GetHorizontalDimension().height);
+			this->SetMinimalSizeAbsolute(NWidgetScrollbar::GetHorizontalDimension().width * 3, NWidgetScrollbar::GetHorizontalDimension().height);
 			break;
 
 		case NWID_VSCROLLBAR:
-			this->SetMinimalSize(NWidgetScrollbar::GetVerticalDimension().width, NWidgetScrollbar::GetVerticalDimension().height * 3);
+			this->SetMinimalSizeAbsolute(NWidgetScrollbar::GetVerticalDimension().width, NWidgetScrollbar::GetVerticalDimension().height * 3);
 			break;
 
 		default: NOT_REACHED();
@@ -2768,7 +2836,7 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 				NWidgetResizeBase *nwrb = dynamic_cast<NWidgetResizeBase *>(*dest);
 				if (nwrb != nullptr) {
 					assert(parts->u.xy.x >= 0 && parts->u.xy.y >= 0);
-					nwrb->SetMinimalSize(ScaleGUITrad(parts->u.xy.x), ScaleGUITrad(parts->u.xy.y));
+					nwrb->SetMinimalSize(parts->u.xy.x, parts->u.xy.y);
 				}
 				break;
 			}
@@ -2814,15 +2882,15 @@ static int MakeNWidget(const NWidgetPart *parts, int count, NWidgetBase **dest,
 			}
 
 			case WPT_PADDING:
-				if (*dest != nullptr) (*dest)->SetPadding(ScaleGUITrad(parts->u.padding.top), ScaleGUITrad(parts->u.padding.right), ScaleGUITrad(parts->u.padding.bottom), ScaleGUITrad(parts->u.padding.left));
+				if (*dest != nullptr) (*dest)->SetPadding(parts->u.padding.top, parts->u.padding.right, parts->u.padding.bottom, parts->u.padding.left);
 				break;
 
 			case WPT_PIPSPACE: {
 				NWidgetPIPContainer *nwc = dynamic_cast<NWidgetPIPContainer *>(*dest);
-				if (nwc != nullptr) nwc->SetPIP(ScaleGUITrad(parts->u.pip.pre), ScaleGUITrad(parts->u.pip.inter), ScaleGUITrad(parts->u.pip.post));
+				if (nwc != nullptr) nwc->SetPIP(parts->u.pip.pre, parts->u.pip.inter, parts->u.pip.post);
 
 				NWidgetBackground *nwb = dynamic_cast<NWidgetBackground *>(*dest);
-				if (nwb != nullptr) nwb->SetPIP(ScaleGUITrad(parts->u.pip.pre), ScaleGUITrad(parts->u.pip.inter), ScaleGUITrad(parts->u.pip.post));
+				if (nwb != nullptr) nwb->SetPIP(parts->u.pip.pre, parts->u.pip.inter, parts->u.pip.post);
 				break;
 			}
 
@@ -3019,7 +3087,7 @@ NWidgetBase *MakeCompanyButtonRows(int *biggest_index, int widget_first, int wid
 	NWidgetHorizontal *hor = nullptr; // Storage for buttons in one row.
 	int hor_length = 0;
 
-	Dimension sprite_size = GetSpriteSize(SPR_COMPANY_ICON);
+	Dimension sprite_size = GetSpriteSize(SPR_COMPANY_ICON, nullptr, ZOOM_LVL_OUT_4X);
 	sprite_size.width  += WD_MATRIX_LEFT + WD_MATRIX_RIGHT;
 	sprite_size.height += WD_MATRIX_TOP + WD_MATRIX_BOTTOM + 1; // 1 for the 'offset' of being pressed
 
diff --git a/src/widget_type.h b/src/widget_type.h
index 077261ff2..200711356 100644
--- a/src/widget_type.h
+++ b/src/widget_type.h
@@ -127,6 +127,7 @@ class NWidgetBase : public ZeroedMemoryAllocator {
 public:
 	NWidgetBase(WidgetType tp);
 
+	virtual void AdjustPaddingForZoom();
 	virtual void SetupSmallestSize(Window *w, bool init_array) = 0;
 	virtual void AssignSizePosition(SizingType sizing, uint x, uint y, uint given_width, uint given_height, bool rtl) = 0;
 
@@ -148,10 +149,11 @@ public:
 	 */
 	inline void SetPadding(uint8 top, uint8 right, uint8 bottom, uint8 left)
 	{
-		this->padding_top = top;
-		this->padding_right = right;
-		this->padding_bottom = bottom;
-		this->padding_left = left;
+		this->uz_padding_top = top;
+		this->uz_padding_right = right;
+		this->uz_padding_bottom = bottom;
+		this->uz_padding_left = left;
+		this->AdjustPaddingForZoom();
 	}
 
 	inline uint GetHorizontalStepSize(SizingType sizing) const;
@@ -195,6 +197,11 @@ public:
 	uint8 padding_bottom; ///< Paddings added to the bottom of the widget. Managed by parent container widget.
 	uint8 padding_left;   ///< Paddings added to the left of the widget. Managed by parent container widget. (parent container may swap this with padding_right for RTL)
 
+	uint8 uz_padding_top;    ///< Unscaled top padding, for resize calculation.
+	uint8 uz_padding_right;  ///< Unscaled right padding, for resize calculation.
+	uint8 uz_padding_bottom; ///< Unscaled bottom padding, for resize calculation.
+	uint8 uz_padding_left;   ///< Unscaled left padding, for resize calculation.
+
 protected:
 	inline void StoreSizePosition(SizingType sizing, uint x, uint y, uint given_width, uint given_height);
 };
@@ -246,7 +253,9 @@ class NWidgetResizeBase : public NWidgetBase {
 public:
 	NWidgetResizeBase(WidgetType tp, uint fill_x, uint fill_y);
 
+	void AdjustPaddingForZoom() override;
 	void SetMinimalSize(uint min_x, uint min_y);
+	void SetMinimalSizeAbsolute(uint min_x, uint min_y);
 	void SetMinimalTextLines(uint8 min_lines, uint8 spacing, FontSize size);
 	void SetFill(uint fill_x, uint fill_y);
 	void SetResize(uint resize_x, uint resize_y);
@@ -255,6 +264,14 @@ public:
 
 	uint min_x; ///< Minimal horizontal size of only this widget.
 	uint min_y; ///< Minimal vertical size of only this widget.
+
+	bool absolute; ///< Set if minimum size is fixed and should not be resized.
+	uint uz_min_x; ///< Unscaled Minimal horizontal size of only this widget.
+	uint uz_min_y; ///< Unscaled Minimal vertical size of only this widget.
+
+	uint8 uz_text_lines;   ///< 'Unscaled' text lines, stored for resize calculation.
+	uint8 uz_text_spacing; ///< 'Unscaled' text padding, stored for resize calculation.
+	FontSize uz_text_size; ///< 'Unscaled' font size, stored for resize calculation.
 };
 
 /** Nested widget flags that affect display and interaction with 'real' widgets. */
@@ -385,6 +402,7 @@ public:
 	NWidgetContainer(WidgetType tp);
 	~NWidgetContainer();
 
+	void AdjustPaddingForZoom() override;
 	void Add(NWidgetBase *wid);
 	void FillNestedArray(NWidgetBase **array, uint length) override;
 
@@ -423,6 +441,7 @@ public:
 
 	void SetIndex(int index);
 
+	void AdjustPaddingForZoom() override;
 	void SetupSmallestSize(Window *w, bool init_array) override;
 	void AssignSizePosition(SizingType sizing, uint x, uint y, uint given_width, uint given_height, bool rtl) override;
 	void FillNestedArray(NWidgetBase **array, uint length) override;
@@ -450,6 +469,7 @@ class NWidgetPIPContainer : public NWidgetContainer {
 public:
 	NWidgetPIPContainer(WidgetType tp, NWidContainerFlags flags = NC_NONE);
 
+	void AdjustPaddingForZoom() override;
 	void SetPIP(uint8 pip_pre, uint8 pip_inter, uint8 pip_post);
 
 	void Draw(const Window *w) override;
@@ -460,6 +480,10 @@ protected:
 	uint8 pip_pre;            ///< Amount of space before first widget.
 	uint8 pip_inter;          ///< Amount of space between widgets.
 	uint8 pip_post;           ///< Amount of space after last widget.
+
+	uint8 uz_pip_pre;         ///< Unscaled space before first widget.
+	uint8 uz_pip_inter;       ///< Unscaled space between widgets.
+	uint8 uz_pip_post;        ///< Unscaled space after last widget.
 };
 
 /**
@@ -565,6 +589,7 @@ public:
 	void Add(NWidgetBase *nwid);
 	void SetPIP(uint8 pip_pre, uint8 pip_inter, uint8 pip_post);
 
+	void AdjustPaddingForZoom() override;
 	void SetupSmallestSize(Window *w, bool init_array) override;
 	void AssignSizePosition(SizingType sizing, uint x, uint y, uint given_width, uint given_height, bool rtl) override;
 
diff --git a/src/widgets/dropdown.cpp b/src/widgets/dropdown.cpp
index f5536f52f..8f4a8634e 100644
--- a/src/widgets/dropdown.cpp
+++ b/src/widgets/dropdown.cpp
@@ -153,7 +153,7 @@ struct DropdownWindow : Window {
 
 		uint items_width = size.width - (scroll ? NWidgetScrollbar::GetVerticalDimension().width : 0);
 		NWidgetCore *nwi = this->GetWidget<NWidgetCore>(WID_DM_ITEMS);
-		nwi->SetMinimalSize(items_width, size.height + 4);
+		nwi->SetMinimalSizeAbsolute(items_width, size.height + 4);
 		nwi->colour = wi_colour;
 
 		nwi = this->GetWidget<NWidgetCore>(WID_DM_SCROLL);
diff --git a/src/window.cpp b/src/window.cpp
index a82afc7cd..a40972600 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -3412,7 +3412,7 @@ void HideVitalWindows()
 }
 
 /** Re-initialize all windows. */
-void ReInitAllWindows()
+void ReInitAllWindows(bool zoom_changed)
 {
 	NWidgetLeaf::InvalidateDimensionCache(); // Reset cached sizes of several widgets.
 	NWidgetScrollbar::InvalidateDimensionCache();
@@ -3421,6 +3421,7 @@ void ReInitAllWindows()
 	InitDepotWindowBlockSizes();
 
 	for (Window *w : Window::IterateFromBack()) {
+		if (zoom_changed) w->nested_root->AdjustPaddingForZoom();
 		w->ReInit();
 	}
 
diff --git a/src/window_func.h b/src/window_func.h
index 20866b34d..fba00944a 100644
--- a/src/window_func.h
+++ b/src/window_func.h
@@ -43,7 +43,11 @@ void DeleteConstructionWindows();
 void HideVitalWindows();
 void ShowVitalWindows();
 
-void ReInitAllWindows();
+/**
+ * Re-initialize all windows.
+ * @param zoom_changed Set if windows are being re-initialized due to a zoom level changed.
+ */
+void ReInitAllWindows(bool zoom_changed);
 
 void SetWindowWidgetDirty(WindowClass cls, WindowNumber number, byte widget_index);
 void SetWindowDirty(WindowClass cls, WindowNumber number);