Merge branch 'master' into jgrpp

# Conflicts:
#	src/core/geometry_type.hpp
#	src/error_gui.cpp
#	src/rail_gui.cpp
#	src/tree_gui.cpp
#	src/vehicle_gui.cpp
#	src/widgets/dropdown.cpp

src/aircraft_cmd.cpp

@@ -265,10 +265,10 @@ void GetAircraftSpriteSize(EngineID engine, uint &width, uint &height, int &xoff
 	VehicleSpriteSeq seq;
 	GetAircraftIcon(engine, image_type, &seq);
 
-	Rect16 rect = seq.GetBounds();
+	Rect rect = ConvertRect<Rect16, Rect>(seq.GetBounds());
 
-	width  = UnScaleGUI(rect.right - rect.left + 1);
-	height = UnScaleGUI(rect.bottom - rect.top + 1);
+	width  = UnScaleGUI(rect.Width());
+	height = UnScaleGUI(rect.Height());
 	xoffs  = UnScaleGUI(rect.left);
 	yoffs  = UnScaleGUI(rect.top);
 }

src/aircraft_gui.cpp

@@ -84,9 +84,9 @@ void DrawAircraftImage(const Vehicle *v, int left, int right, int y, VehicleID s
 	VehicleSpriteSeq seq;
 	v->GetImage(rtl ? DIR_E : DIR_W, image_type, &seq);
 
-	Rect16 rect = seq.GetBounds();
+	Rect rect = ConvertRect<Rect16, Rect>(seq.GetBounds());
 
-	int width = UnScaleGUI(rect.right - rect.left + 1);
+	int width = UnScaleGUI(rect.Width());
 	int x_offs = UnScaleGUI(rect.left);
 	int x = rtl ? right - width - x_offs : left - x_offs;
 	bool helicopter = v->subtype == AIR_HELICOPTER;
@@ -107,6 +107,6 @@ void DrawAircraftImage(const Vehicle *v, int left, int right, int y, VehicleID s
 	if (v->index == selection) {
 		x += x_offs;
 		y += UnScaleGUI(rect.top) + y_offs - heli_offs;
-		DrawFrameRect(x - 1, y - 1, x + width + 1, y + UnScaleGUI(rect.bottom - rect.top + 1) + heli_offs + 1, COLOUR_WHITE, FR_BORDERONLY);
+		DrawFrameRect(x - 1, y - 1, x + width + 1, y + UnScaleGUI(rect.Height()) + heli_offs + 1, COLOUR_WHITE, FR_BORDERONLY);
 	}
 }

src/airport_gui.cpp

@@ -392,7 +392,7 @@ public:
 			case WID_AP_AIRPORT_SPRITE:
 				if (this->preview_sprite != 0) {
 					Dimension d = GetSpriteSize(this->preview_sprite);
-					DrawSprite(this->preview_sprite, COMPANY_SPRITE_COLOUR(_local_company), (r.left + r.right - d.width) / 2, (r.top + r.bottom - d.height) / 2);
+					DrawSprite(this->preview_sprite, COMPANY_SPRITE_COLOUR(_local_company), CenterBounds(r.left, r.right, d.width), CenterBounds(r.top, r.bottom, d.height));
 				}
 				break;
 

src/bitmap_type.h

@@ -59,8 +59,8 @@ public:
 	void Initialize(const Rect &r)
 	{
 		this->tile = TileXY(r.left, r.top);
-		this->w = r.right - r.left + 1;
-		this->h = r.bottom - r.top + 1;
+		this->w = r.Width();
+		this->h = r.Height();
 		this->data.clear();
 		this->data.resize(Index(w, h));
 	}

src/company_gui.cpp

@@ -651,18 +651,17 @@ public:
 		return true;
 	}
 
-	void Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const override
+	void Draw(const Rect &r, bool sel, Colours bg_colour) const override
 	{
 		bool rtl = _current_text_dir == TD_RTL;
-		int height = bottom - top;
-		int icon_y_offset = height / 2;
-		int text_y_offset = (height - FONT_HEIGHT_NORMAL) / 2 + 1;
+		int icon_y = CenterBounds(r.top, r.bottom, 0);
+		int text_y = CenterBounds(r.top, r.bottom, FONT_HEIGHT_NORMAL);
 		DrawSprite(SPR_VEH_BUS_SIDE_VIEW, PALETTE_RECOLOUR_START + (this->result % COLOUR_END),
-				rtl ? right - 2 - ScaleGUITrad(14) : left + ScaleGUITrad(14) + 2,
-				top + icon_y_offset);
-		DrawString(rtl ? left + 2 : left + ScaleGUITrad(28) + 4,
-				rtl ? right - ScaleGUITrad(28) - 4 : right - 2,
-				top + text_y_offset, this->String(), sel ? TC_WHITE : TC_BLACK);
+				rtl ? r.right - 2 - ScaleGUITrad(14) : r.left + ScaleGUITrad(14) + 2,
+				icon_y);
+		DrawString(rtl ? r.left + 2 : r.left + ScaleGUITrad(28) + 4,
+				rtl ? r.right - ScaleGUITrad(28) - 4 : r.right - 2,
+				text_y, this->String(), sel ? TC_WHITE : TC_BLACK);
 	}
 };
 
@@ -2567,7 +2566,7 @@ struct CompanyWindow : Window
 				Point offset;
 				Dimension d = GetSpriteSize(SPR_VEH_BUS_SW_VIEW, &offset);
 				d.height -= offset.y;
-				DrawSprite(SPR_VEH_BUS_SW_VIEW, COMPANY_SPRITE_COLOUR(c->index), r.left - offset.x, (r.top + r.bottom - d.height) / 2 - offset.y);
+				DrawSprite(SPR_VEH_BUS_SW_VIEW, COMPANY_SPRITE_COLOUR(c->index), r.left - offset.x, CenterBounds(r.top, r.bottom, d.height) - offset.y);
 				break;
 			}
 

src/engine_gui.cpp

@@ -108,17 +108,16 @@ struct EnginePreviewWindow : Window {
 
 		EngineID engine = this->window_number;
 		SetDParam(0, GetEngineCategoryName(engine));
-		int y = r.top + GetStringHeight(STR_ENGINE_PREVIEW_MESSAGE, r.right - r.left + 1);
-		y = DrawStringMultiLine(r.left, r.right, r.top, y, STR_ENGINE_PREVIEW_MESSAGE, TC_FROMSTRING, SA_CENTER) + WD_PAR_VSEP_WIDE;
+		int y = DrawStringMultiLine(r, STR_ENGINE_PREVIEW_MESSAGE, TC_FROMSTRING, SA_HOR_CENTER | SA_TOP) + WD_PAR_VSEP_WIDE;
 
 		SetDParam(0, engine);
-		DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, STR_ENGINE_NAME, TC_BLACK, SA_HOR_CENTER);
+		DrawString(r.left, r.right, y, STR_ENGINE_NAME, TC_BLACK, SA_HOR_CENTER);
 		y += FONT_HEIGHT_NORMAL;
 
-		DrawVehicleEngine(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, this->width >> 1, y + this->vehicle_space / 2, engine, GetEnginePalette(engine, _local_company), EIT_PREVIEW);
+		DrawVehicleEngine(r.left, r.right, this->width >> 1, y + this->vehicle_space / 2, engine, GetEnginePalette(engine, _local_company), EIT_PREVIEW);
 
 		y += this->vehicle_space;
-		DrawStringMultiLine(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, y, r.bottom, GetEngineInfoString(engine), TC_FROMSTRING, SA_CENTER);
+		DrawStringMultiLine(r.left, r.right, y, r.bottom, GetEngineInfoString(engine), TC_FROMSTRING, SA_CENTER);
 	}
 
 	void OnClick(Point pt, int widget, int click_count) override

src/error_gui.cpp

@@ -35,7 +35,7 @@ static const NWidgetPart _nested_errmsg_widgets[] = {
 		NWidget(WWT_CAPTION, COLOUR_RED, WID_EM_CAPTION), SetDataTip(STR_ERROR_MESSAGE_CAPTION, STR_NULL),
 	EndContainer(),
 	NWidget(WWT_PANEL, COLOUR_RED),
-		NWidget(WWT_EMPTY, COLOUR_RED, WID_EM_MESSAGE), SetPadding(0, 2, 0, 2), SetMinimalSize(236, 32),
+		NWidget(WWT_EMPTY, COLOUR_RED, WID_EM_MESSAGE), SetPadding(WD_FRAMETEXT_TOP, WD_FRAMETEXT_RIGHT, WD_FRAMETEXT_BOTTOM, WD_FRAMETEXT_LEFT), SetFill(1, 0), SetMinimalSize(236, 0),
 	EndContainer(),
 };
 
@@ -52,9 +52,9 @@ static const NWidgetPart _nested_errmsg_face_widgets[] = {
 		NWidget(WWT_CAPTION, COLOUR_RED, WID_EM_CAPTION), SetDataTip(STR_ERROR_MESSAGE_CAPTION_OTHER_COMPANY, STR_NULL),
 	EndContainer(),
 	NWidget(WWT_PANEL, COLOUR_RED),
-		NWidget(NWID_HORIZONTAL), SetPIP(2, 1, 2),
-			NWidget(WWT_EMPTY, COLOUR_RED, WID_EM_FACE), SetMinimalSize(92, 119), SetFill(0, 1), SetPadding(2, 0, 1, 0),
-			NWidget(WWT_EMPTY, COLOUR_RED, WID_EM_MESSAGE), SetFill(0, 1), SetMinimalSize(238, 123),
+		NWidget(NWID_HORIZONTAL),
+			NWidget(WWT_EMPTY, COLOUR_RED, WID_EM_FACE), SetPadding(2, 0, 2, 2), SetFill(0, 1), SetMinimalSize(92, 119),
+			NWidget(WWT_EMPTY, COLOUR_RED, WID_EM_MESSAGE), SetPadding(WD_FRAMETEXT_TOP, WD_FRAMETEXT_RIGHT, WD_FRAMETEXT_BOTTOM, WD_FRAMETEXT_LEFT), SetFill(1, 1), SetMinimalSize(236, 0),
 		EndContainer(),
 	EndContainer(),
 };
@@ -203,14 +203,13 @@ public:
 				CopyInDParam(0, this->decode_params, lengthof(this->decode_params));
 				if (this->textref_stack_size > 0) StartTextRefStackUsage(this->textref_stack_grffile, this->textref_stack_size, this->textref_stack);
 
-				int text_width = std::max(0, (int)size->width - WD_FRAMETEXT_LEFT - WD_FRAMETEXT_RIGHT);
-				this->height_summary = GetStringHeight(this->summary_msg, text_width);
-				this->height_detailed = (this->detailed_msg == INVALID_STRING_ID) ? 0 : GetStringHeight(this->detailed_msg, text_width);
-				this->height_extra = (this->extra_msg == INVALID_STRING_ID) ? 0 : GetStringHeight(this->extra_msg, text_width);
+				this->height_summary = GetStringHeight(this->summary_msg, size->width);
+				this->height_detailed = (this->detailed_msg == INVALID_STRING_ID) ? 0 : GetStringHeight(this->detailed_msg, size->width);
+				this->height_extra = (this->extra_msg == INVALID_STRING_ID) ? 0 : GetStringHeight(this->extra_msg, size->width);
 
 				if (this->textref_stack_size > 0) StopTextRefStackUsage();
 
-				uint panel_height = WD_FRAMERECT_TOP + this->height_summary + WD_FRAMERECT_BOTTOM;
+				uint panel_height = this->height_summary;
 				if (this->detailed_msg != INVALID_STRING_ID) panel_height += this->height_detailed + WD_PAR_VSEP_WIDE;
 				if (this->extra_msg != INVALID_STRING_ID) panel_height += this->height_extra + WD_PAR_VSEP_WIDE;
 
@@ -287,34 +286,25 @@ public:
 				if (this->textref_stack_size > 0) StartTextRefStackUsage(this->textref_stack_grffile, this->textref_stack_size, this->textref_stack);
 
 				if (this->detailed_msg == INVALID_STRING_ID) {
-					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, r.top + WD_FRAMERECT_TOP, r.bottom - WD_FRAMERECT_BOTTOM,
-							this->summary_msg, TC_FROMSTRING, SA_CENTER);
+					DrawStringMultiLine(r, this->summary_msg, TC_FROMSTRING, SA_CENTER);
 				} else if (this->extra_msg == INVALID_STRING_ID) {
-					int extra = (r.bottom - r.top + 1 - this->height_summary - this->height_detailed - WD_PAR_VSEP_WIDE) / 2;
+					/* Extra space when message is shorter than company face window */
+					int extra = (r.Height() - this->height_summary - this->height_detailed - WD_PAR_VSEP_WIDE) / 2;
 
 					/* Note: NewGRF supplied error message often do not start with a colour code, so default to white. */
-					int top = r.top + WD_FRAMERECT_TOP;
-					int bottom = top + this->height_summary + extra;
-					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->summary_msg, TC_WHITE, SA_CENTER);
-
-					bottom = r.bottom - WD_FRAMERECT_BOTTOM;
-					top = bottom - this->height_detailed - extra;
-					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->detailed_msg, TC_WHITE, SA_CENTER);
+					DrawStringMultiLine(r.WithHeight(this->height_summary + extra, false), this->summary_msg, TC_WHITE, SA_CENTER);
+					DrawStringMultiLine(r.WithHeight(this->height_detailed + extra, true), this->detailed_msg, TC_WHITE, SA_CENTER);
 				} else {
-					int extra = (r.bottom - r.top + 1 - this->height_summary - this->height_detailed - this->height_extra - (WD_PAR_VSEP_WIDE * 2)) / 3;
+					/* Extra space when message is shorter than company face window */
+					int extra = (r.Height() - this->height_summary - this->height_detailed - this->height_extra - (WD_PAR_VSEP_WIDE * 2)) / 3;
 
 					/* Note: NewGRF supplied error message often do not start with a colour code, so default to white. */
-					int top = r.top + WD_FRAMERECT_TOP;
-					int bottom = top + this->height_summary + extra;
-					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->summary_msg, TC_WHITE, SA_CENTER);
-
-					top = bottom + WD_PAR_VSEP_WIDE;
-					bottom = top + this->height_detailed + extra;
-					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->detailed_msg, TC_WHITE, SA_CENTER);
-
-					bottom = r.bottom - WD_FRAMERECT_BOTTOM;
-					top = bottom - this->height_extra - extra;
-					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->extra_msg, TC_WHITE, SA_CENTER);
+					Rect top_section = r.WithHeight(this->height_summary + extra, false);
+					Rect bottom_section = r.WithHeight(this->height_extra + extra, true);
+					Rect middle_section = { top_section.left, top_section.bottom, top_section.right, bottom_section.top };
+					DrawStringMultiLine(top_section, this->summary_msg, TC_WHITE, SA_CENTER);
+					DrawStringMultiLine(middle_section, this->detailed_msg, TC_WHITE, SA_CENTER);
+					DrawStringMultiLine(bottom_section, this->extra_msg, TC_WHITE, SA_CENTER);
 				}
 
 				if (this->textref_stack_size > 0) StopTextRefStackUsage();

src/gfx_func.h

@@ -115,6 +115,42 @@ void GfxDrawLine(const DrawPixelInfo *dpi, int left, int top, int right, int bot
 inline void GfxDrawLine(int left, int top, int right, int bottom, int colour, int width = 1, int dash = 0) { GfxDrawLine(_cur_dpi, left, top, right, bottom, colour, width, dash); }
 void DrawBox(const DrawPixelInfo *dpi, int x, int y, int dx1, int dy1, int dx2, int dy2, int dx3, int dy3);
 
+/* Versions of DrawString/DrawStringMultiLine that accept a Rect instead of separate left, right, top and bottom parameters. */
+static inline int DrawString(const Rect &r, const char *str, TextColour colour = TC_FROMSTRING, StringAlignment align = SA_LEFT, bool underline = false, FontSize fontsize = FS_NORMAL)
+{
+	return DrawString(r.left, r.right, r.top, str, colour, align, underline, fontsize);
+}
+
+static inline int DrawString(const Rect &r, const std::string &str, TextColour colour = TC_FROMSTRING, StringAlignment align = SA_LEFT, bool underline = false, FontSize fontsize = FS_NORMAL)
+{
+	return DrawString(r.left, r.right, r.top, str, colour, align, underline, fontsize);
+}
+
+static inline int DrawString(const Rect &r, StringID str, TextColour colour = TC_FROMSTRING, StringAlignment align = SA_LEFT, bool underline = false, FontSize fontsize = FS_NORMAL)
+{
+	return DrawString(r.left, r.right, r.top, str, colour, align, underline, fontsize);
+}
+
+static inline int DrawStringMultiLine(const Rect &r, const char *str, TextColour colour = TC_FROMSTRING, StringAlignment align = (SA_TOP | SA_LEFT), bool underline = false, FontSize fontsize = FS_NORMAL)
+{
+	return DrawStringMultiLine(r.left, r.right, r.top, r.bottom, str, colour, align, underline, fontsize);
+}
+
+static inline int DrawStringMultiLine(const Rect &r, const std::string &str, TextColour colour = TC_FROMSTRING, StringAlignment align = (SA_TOP | SA_LEFT), bool underline = false, FontSize fontsize = FS_NORMAL)
+{
+	return DrawStringMultiLine(r.left, r.right, r.top, r.bottom, str, colour, align, underline, fontsize);
+}
+
+static inline int DrawStringMultiLine(const Rect &r, StringID str, TextColour colour = TC_FROMSTRING, StringAlignment align = (SA_TOP | SA_LEFT), bool underline = false, FontSize fontsize = FS_NORMAL)
+{
+	return DrawStringMultiLine(r.left, r.right, r.top, r.bottom, str, colour, align, underline, fontsize);
+}
+
+static inline void GfxFillRect(const Rect &r, int colour, FillRectMode mode = FILLRECT_OPAQUE)
+{
+	GfxFillRect(r.left, r.top, r.right, r.bottom, colour, mode);
+}
+
 Dimension GetStringBoundingBox(const char *str, FontSize start_fontsize = FS_NORMAL);
 Dimension GetStringBoundingBox(const std::string &str, FontSize start_fontsize = FS_NORMAL);
 Dimension GetStringBoundingBox(StringID strid, FontSize start_fontsize = FS_NORMAL);
@@ -147,7 +183,7 @@ bool FillDrawPixelInfo(DrawPixelInfo *n, int left, int top, int width, int heigh
  */
 static inline int CenterBounds(int min, int max, int size)
 {
-	return min + (max - min - size + 1) / 2;
+	return (min + max - size + 1) / 2;
 }
 
 /* window.cpp */

src/graph_gui.cpp

@@ -1263,7 +1263,7 @@ struct PerformanceRatingDetailWindow : Window {
 			CompanyID cid = (CompanyID)(widget - WID_PRD_COMPANY_FIRST);
 			int offset = (cid == this->company) ? 1 : 0;
 			Dimension sprite_size = GetSpriteSize(SPR_COMPANY_ICON);
-			DrawCompanyIcon(cid, (r.left + r.right - sprite_size.width) / 2 + offset, (r.top + r.bottom - sprite_size.height) / 2 + offset);
+			DrawCompanyIcon(cid, CenterBounds(r.left, r.right, sprite_size.width) + offset, CenterBounds(r.top, r.bottom, sprite_size.height) + offset);
 			return;
 		}
 

src/industry_gui.cpp

@@ -2957,8 +2957,8 @@ struct IndustryCargoesWindow : public Window {
 		if (widget != WID_IC_PANEL) return;
 
 		DrawPixelInfo tmp_dpi, *old_dpi;
-		int width = r.right - r.left + 1;
-		int height = r.bottom - r.top + 1 - WD_FRAMERECT_TOP - WD_FRAMERECT_BOTTOM;
+		int width = r.Width();
+		int height = r.Height() - WD_FRAMERECT_TOP - WD_FRAMERECT_BOTTOM;
 		if (!FillDrawPixelInfo(&tmp_dpi, r.left + WD_FRAMERECT_LEFT, r.top + WD_FRAMERECT_TOP, width, height)) return;
 		old_dpi = _cur_dpi;
 		_cur_dpi = &tmp_dpi;

src/linkgraph/linkgraph_gui.cpp

@@ -761,7 +761,7 @@ void LinkGraphLegendWindow::DrawWidget(const Rect &r, int widget) const
 		if (this->IsWidgetDisabled(widget)) return;
 		CompanyID cid = (CompanyID)(widget - WID_LGL_COMPANY_FIRST);
 		Dimension sprite_size = GetSpriteSize(SPR_COMPANY_ICON);
-		DrawCompanyIcon(cid, (r.left + r.right + 1 - sprite_size.width) / 2, (r.top + r.bottom + 1 - sprite_size.height) / 2);
+		DrawCompanyIcon(cid, CenterBounds(r.left, r.right, sprite_size.width), CenterBounds(r.top, r.bottom, sprite_size.height));
 	}
 	if (IsInsideMM(widget, WID_LGL_SATURATION_FIRST, WID_LGL_SATURATION_LAST + 1)) {
 		uint8 colour = LinkGraphOverlay::LINK_COLOURS[_settings_client.gui.linkgraph_colours][widget - WID_LGL_SATURATION_FIRST];
@@ -775,14 +775,14 @@ void LinkGraphLegendWindow::DrawWidget(const Rect &r, int widget) const
 			str = STR_LINKGRAPH_LEGEND_SATURATED;
 		}
 		if (str != STR_NULL) {
-			DrawString(r.left, r.right, (r.top + r.bottom + 1 - FONT_HEIGHT_SMALL) / 2, str, GetContrastColour(colour) | TC_FORCED, SA_HOR_CENTER);
+			DrawString(r.left, r.right, CenterBounds(r.top, r.bottom, FONT_HEIGHT_SMALL), str, GetContrastColour(colour) | TC_FORCED, SA_HOR_CENTER);
 		}
 	}
 	if (IsInsideMM(widget, WID_LGL_CARGO_FIRST, WID_LGL_CARGO_LAST + 1)) {
 		if (this->IsWidgetDisabled(widget)) return;
 		CargoSpec *cargo = CargoSpec::Get(widget - WID_LGL_CARGO_FIRST);
 		GfxFillRect(r.left + 2, r.top + 2, r.right - 2, r.bottom - 2, cargo->legend_colour);
-		DrawString(r.left, r.right, (r.top + r.bottom + 1 - FONT_HEIGHT_SMALL) / 2, cargo->abbrev, GetContrastColour(cargo->legend_colour, 73), SA_HOR_CENTER);
+		DrawString(r.left, r.right, CenterBounds(r.top, r.bottom, FONT_HEIGHT_SMALL), cargo->abbrev, GetContrastColour(cargo->legend_colour, 73), SA_HOR_CENTER);
 	}
 }
 

src/misc_gui.cpp

@@ -882,7 +882,7 @@ void QueryString::DrawEditBox(const Window *w, int wid) const
 	int bottom = wi->pos_y + wi->current_y - 1;
 
 	DrawFrameRect(clearbtn_left, top, clearbtn_right, bottom, wi->colour, wi->IsLowered() ? FR_LOWERED : FR_NONE);
-	DrawSprite(rtl ? SPR_IMG_DELETE_RIGHT : SPR_IMG_DELETE_LEFT, PAL_NONE, clearbtn_left + WD_IMGBTN_LEFT + (wi->IsLowered() ? 1 : 0), (top + bottom - sprite_size.height) / 2 + (wi->IsLowered() ? 1 : 0));
+	DrawSprite(rtl ? SPR_IMG_DELETE_RIGHT : SPR_IMG_DELETE_LEFT, PAL_NONE, clearbtn_left + WD_IMGBTN_LEFT + (wi->IsLowered() ? 1 : 0), CenterBounds(top, bottom, sprite_size.height) + (wi->IsLowered() ? 1 : 0));
 	if (this->text.bytes == 1) GfxFillRect(clearbtn_left + 1, top + 1, clearbtn_right - 1, bottom - 1, _colour_gradient[wi->colour & 0xF][2], FILLRECT_CHECKER);
 
 	DrawFrameRect(left, top, right, bottom, wi->colour, FR_LOWERED | FR_DARKENED);

src/newgrf_debug_gui.cpp

@@ -474,7 +474,7 @@ struct NewGRFInspectWindow : Window {
 					if (u == v) sel_end = total_width;
 				}
 
-				int width = r.right + 1 - r.left - WD_BEVEL_LEFT - WD_BEVEL_RIGHT;
+				int width = r.Width() - WD_BEVEL_LEFT - WD_BEVEL_RIGHT;
 				int skip = 0;
 				if (total_width > width) {
 					int sel_center = (sel_start + sel_end) / 2;
@@ -483,7 +483,7 @@ struct NewGRFInspectWindow : Window {
 
 				GrfSpecFeature f = GetFeatureNum(this->window_number);
 				int h = GetVehicleImageCellSize((VehicleType)(VEH_TRAIN + (f - GSF_TRAINS)), EIT_IN_DEPOT).height;
-				int y = (r.top + r.bottom - h) / 2;
+				int y = CenterBounds(r.top, r.bottom, h);
 				DrawVehicleImage(v->First(), r.left + WD_BEVEL_LEFT, r.right - WD_BEVEL_RIGHT, y + 1, INVALID_VEHICLE, EIT_IN_DETAILS, skip);
 
 				/* Highlight the articulated part (this is different to the whole-vehicle highlighting of DrawVehicleImage */
@@ -1301,8 +1301,8 @@ struct SpriteAlignerWindow : Window {
 			case WID_SA_SPRITE: {
 				/* Center the sprite ourselves */
 				const Sprite *spr = GetSprite(this->current_sprite, ST_NORMAL);
-				int width  = r.right  - r.left + 1 - WD_BEVEL_LEFT - WD_BEVEL_RIGHT;
-				int height = r.bottom - r.top  + 1 - WD_BEVEL_TOP - WD_BEVEL_BOTTOM;
+				int width  = r.Width()  - WD_BEVEL_LEFT - WD_BEVEL_RIGHT;
+				int height = r.Height() - WD_BEVEL_TOP - WD_BEVEL_BOTTOM;
 				int x = -UnScaleGUI(spr->x_offs) + (width  - UnScaleGUI(spr->width) ) / 2;
 				int y = -UnScaleGUI(spr->y_offs) + (height - UnScaleGUI(spr->height)) / 2;
 

src/newgrf_gui.cpp

@@ -901,7 +901,7 @@ struct NewGRFWindow : public Window, NewGRFScanCallback {
 			case WID_NS_NEWGRF_INFO_TITLE:
 				/* Create the nice grayish rectangle at the details top. */
 				GfxFillRect(r.left + 1, r.top + 1, r.right - 1, r.bottom - 1, PC_DARK_BLUE);
-				DrawString(r.left, r.right, (r.top + r.bottom - FONT_HEIGHT_NORMAL) / 2, STR_NEWGRF_SETTINGS_INFO_TITLE, TC_FROMSTRING, SA_HOR_CENTER);
+				DrawString(r.left, r.right, CenterBounds(r.top, r.bottom, FONT_HEIGHT_NORMAL), STR_NEWGRF_SETTINGS_INFO_TITLE, TC_FROMSTRING, SA_HOR_CENTER);
 				break;
 
 			case WID_NS_NEWGRF_INFO: {

src/news_gui.cpp

@@ -465,7 +465,7 @@ struct NewsWindow : Window {
 			case WID_N_VEH_SPR: {
 				assert(this->ni->reftype1 == NR_ENGINE);
 				EngineID engine = this->ni->ref1;
-				DrawVehicleEngine(r.left, r.right, (r.left + r.right) / 2, (r.top + r.bottom) / 2, engine, GetEnginePalette(engine, _local_company), EIT_PREVIEW);
+				DrawVehicleEngine(r.left, r.right, CenterBounds(r.left, r.right, 0), CenterBounds(r.top, r.bottom, 0), engine, GetEnginePalette(engine, _local_company), EIT_PREVIEW);
 				GfxFillRect(r.left, r.top, r.right, r.bottom, PALETTE_NEWSPAPER, FILLRECT_RECOLOUR);
 				break;
 			}

src/object_gui.cpp

@@ -351,7 +351,7 @@ public:
 
 				DrawPixelInfo tmp_dpi;
 				/* Set up a clipping area for the preview. */
-				if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.right - r.left + 1, r.bottom - r.top + 1)) {
+				if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.Width(), r.Height())) {
 					DrawPixelInfo *old_dpi = _cur_dpi;
 					_cur_dpi = &tmp_dpi;
 					if (spec->grf_prop.grffile == nullptr) {
@@ -378,7 +378,7 @@ public:
 				}
 				DrawPixelInfo tmp_dpi;
 				/* Set up a clipping area for the preview. */
-				if (FillDrawPixelInfo(&tmp_dpi, r.left + 1, r.top, (r.right - 1) - (r.left + 1) + 1, r.bottom - r.top + 1)) {
+				if (FillDrawPixelInfo(&tmp_dpi, r.left + 1, r.top, (r.right - 1) - (r.left + 1) + 1, r.Height())) {
 					DrawPixelInfo *old_dpi = _cur_dpi;
 					_cur_dpi = &tmp_dpi;
 					if (spec->grf_prop.grffile == nullptr) {

src/rail_gui.cpp

@@ -1398,7 +1398,7 @@ public:
 		switch (GB(widget, 0, 16)) {
 			case WID_BRAS_PLATFORM_DIR_X:
 				/* Set up a clipping area for the '/' station preview */
-				if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.right - r.left + 1, r.bottom - r.top + 1)) {
+				if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.Width(), r.Height())) {
 					DrawPixelInfo *old_dpi = _cur_dpi;
 					_cur_dpi = &tmp_dpi;
 					int x = ScaleGUITrad(31) + 1;
@@ -1412,7 +1412,7 @@ public:
 
 			case WID_BRAS_PLATFORM_DIR_Y:
 				/* Set up a clipping area for the '\' station preview */
-				if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.right - r.left + 1, r.bottom - r.top + 1)) {
+				if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.Width(), r.Height())) {
 					DrawPixelInfo *old_dpi = _cur_dpi;
 					_cur_dpi = &tmp_dpi;
 					int x = ScaleGUITrad(31) + 1;
@@ -1449,7 +1449,7 @@ public:
 				}
 
 				/* Set up a clipping area for the station preview. */
-				if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.right - r.left + 1, r.bottom - r.top + 1)) {
+				if (FillDrawPixelInfo(&tmp_dpi, r.left, r.top, r.Width(), r.Height())) {
 					DrawPixelInfo *old_dpi = _cur_dpi;
 					_cur_dpi = &tmp_dpi;
 					int x = ScaleGUITrad(31) + 1;
@@ -1822,15 +1822,13 @@ private:
 	 * @param widget_index index of this widget in the window
 	 * @param image        the sprite to draw
 	 */
-	void DrawSignalSprite(byte widget_index, PalSpriteID image) const
+	void DrawSignalSprite(const Rect &r, int widget_index, PalSpriteID image) const
 	{
 		Point offset;
 		Dimension sprite_size = GetSpriteSize(image.sprite, &offset);
-		const NWidgetBase *widget = this->GetWidget<NWidgetBase>(widget_index);
-		int x = widget->pos_x - offset.x +
-				(widget->current_x - sprite_size.width + offset.x) / 2;  // centered
-		int y = widget->pos_y - sig_sprite_bottom_offset + WD_IMGBTN_TOP +
-				(widget->current_y - WD_IMGBTN_TOP - WD_IMGBTN_BOTTOM + sig_sprite_size.height) / 2; // aligned to bottom
+		int x = CenterBounds(r.left, r.right, sprite_size.width - offset.x);
+		int y = r.top - sig_sprite_bottom_offset + WD_IMGBTN_TOP +
+				(r.bottom - r.top - WD_IMGBTN_TOP - WD_IMGBTN_BOTTOM + sig_sprite_size.height) / 2; // aligned to bottom
 
 		DrawSprite(image.sprite, image.pal,
 				x + this->IsWidgetLowered(widget_index),
@@ -2005,7 +2003,7 @@ public:
 				sprite = GetRailTypeInfo(_cur_railtype)->gui_sprites.signals[type][var][this->IsWidgetLowered(widget)];
 			}
 
-			this->DrawSignalSprite(widget, sprite);
+			this->DrawSignalSprite(r, widget, sprite);
 		}
 	}
 

src/roadveh_cmd.cpp

@@ -174,10 +174,10 @@ void GetRoadVehSpriteSize(EngineID engine, uint &width, uint &height, int &xoffs
 	VehicleSpriteSeq seq;
 	GetRoadVehIcon(engine, image_type, &seq);
 
-	Rect16 rect = seq.GetBounds();
+	Rect rect = ConvertRect<Rect16, Rect>(seq.GetBounds());
 
-	width  = UnScaleGUI(rect.right - rect.left + 1);
-	height = UnScaleGUI(rect.bottom - rect.top + 1);
+	width  = UnScaleGUI(rect.Width());
+	height = UnScaleGUI(rect.Height());
 	xoffs  = UnScaleGUI(rect.left);
 	yoffs  = UnScaleGUI(rect.top);
 }

src/script/api/script_tilelist.cpp

@@ -155,7 +155,7 @@ ScriptTileList_StationType::ScriptTileList_StationType(StationID station_id, Scr
 	if ((station_type & ScriptStation::STATION_AIRPORT) != 0)    station_type_value |= (1 << ::STATION_AIRPORT) | (1 << ::STATION_OILRIG);
 	if ((station_type & ScriptStation::STATION_DOCK) != 0)       station_type_value |= (1 << ::STATION_DOCK)    | (1 << ::STATION_OILRIG);
 
-	TileArea ta(::TileXY(rect->left, rect->top), rect->right - rect->left + 1, rect->bottom - rect->top + 1);
+	TileArea ta(::TileXY(rect->left, rect->top), rect->Width(), rect->Height());
 	for (TileIndex cur_tile : ta) {
 		if (!::IsTileType(cur_tile, MP_STATION)) continue;
 		if (::GetStationIndex(cur_tile) != station_id) continue;

src/ship_cmd.cpp

@@ -127,10 +127,10 @@ void GetShipSpriteSize(EngineID engine, uint &width, uint &height, int &xoffs, i
 	VehicleSpriteSeq seq;
 	GetShipIcon(engine, image_type, &seq);
 
-	Rect16 rect = seq.GetBounds();
+	Rect rect = ConvertRect<Rect16, Rect>(seq.GetBounds());
 
-	width  = UnScaleGUI(rect.right - rect.left + 1);
-	height = UnScaleGUI(rect.bottom - rect.top + 1);
+	width  = UnScaleGUI(rect.Width());
+	height = UnScaleGUI(rect.Height());
 	xoffs  = UnScaleGUI(rect.left);
 	yoffs  = UnScaleGUI(rect.top);
 }

src/ship_gui.cpp

@@ -37,9 +37,9 @@ void DrawShipImage(const Vehicle *v, int left, int right, int y, VehicleID selec
 	VehicleSpriteSeq seq;
 	v->GetImage(rtl ? DIR_E : DIR_W, image_type, &seq);
 
-	Rect16 rect = seq.GetBounds();
+	Rect rect = ConvertRect<Rect16, Rect>(seq.GetBounds());
 
-	int width = UnScaleGUI(rect.right - rect.left + 1);
+	int width = UnScaleGUI(rect.Width());
 	int x_offs = UnScaleGUI(rect.left);
 	int x = rtl ? right - width - x_offs : left - x_offs;
 
@@ -49,7 +49,7 @@ void DrawShipImage(const Vehicle *v, int left, int right, int y, VehicleID selec
 	if (v->index == selection) {
 		x += x_offs;
 		y += UnScaleGUI(rect.top);
-		DrawFrameRect(x - 1, y - 1, x + width + 1, y + UnScaleGUI(rect.bottom - rect.top + 1) + 1, COLOUR_WHITE, FR_BORDERONLY);
+		DrawFrameRect(x - 1, y - 1, x + width + 1, y + UnScaleGUI(rect.Height()) + 1, COLOUR_WHITE, FR_BORDERONLY);
 	}
 }
 

src/smallmap_gui.cpp

@@ -1242,13 +1242,13 @@ void SmallMapWindow::RebuildColourIndexIfNecessary()
 	switch (widget) {
 		case WID_SM_MAP: {
 			DrawPixelInfo new_dpi;
-			if (!FillDrawPixelInfo(&new_dpi, r.left + 1, r.top + 1, r.right - r.left - 1, r.bottom - r.top - 1)) return;
+			if (!FillDrawPixelInfo(&new_dpi, r.left + 1, r.top + 1, r.Width(), r.Height())) return;
 			this->DrawSmallMap(&new_dpi);
 			break;
 		}
 
 		case WID_SM_LEGEND: {
-			uint columns = this->GetNumberColumnsLegend(r.right - r.left + 1);
+			uint columns = this->GetNumberColumnsLegend(r.Width());
 			uint number_of_rows = this->GetNumberRowsLegend(columns);
 			bool rtl = _current_text_dir == TD_RTL;
 			uint y_org = r.top + WD_FRAMERECT_TOP;
@@ -1750,8 +1750,8 @@ void SmallMapWindow::SmallMapCenterOnCurrentPos()
  */
 Point SmallMapWindow::GetStationMiddle(const Station *st) const
 {
-	int x = (st->rect.right + st->rect.left + 1) / 2;
-	int y = (st->rect.bottom + st->rect.top + 1) / 2;
+	int x = CenterBounds(st->rect.left, st->rect.right, 0);
+	int y = CenterBounds(st->rect.top, st->rect.bottom, 0);
 	Point ret = this->RemapTile(x, y);
 
 	/* Same magic 3 as in DrawVehicles; that's where I got it from.

src/station.cpp

@@ -614,8 +614,8 @@ CommandCost StationRect::BeforeAddTile(TileIndex tile, StationRectMode mode)
 		Rect new_rect = {std::min(x, this->left), std::min(y, this->top), std::max(x, this->right), std::max(y, this->bottom)};
 
 		/* check new rect dimensions against preset max */
-		int w = new_rect.right - new_rect.left + 1;
-		int h = new_rect.bottom - new_rect.top + 1;
+		int w = new_rect.Width();
+		int h = new_rect.Height();
 		if (mode != ADD_FORCE && (w > _settings_game.station.station_spread || h > _settings_game.station.station_spread)) {
 			dbg_assert(mode != ADD_TRY);
 			return_cmd_error(STR_ERROR_STATION_TOO_SPREAD_OUT);

src/station_gui.cpp

@@ -562,7 +562,7 @@ public:
 					int cg_ofst = HasBit(this->cargo_filter, cs->Index()) ? 1 : 0;
 					GfxFillRect(r.left + cg_ofst + 1, r.top + cg_ofst + 1, r.right - 1 + cg_ofst, r.bottom - 1 + cg_ofst, cs->rating_colour);
 					TextColour tc = GetContrastColour(cs->rating_colour);
-					DrawString(r.left + cg_ofst, r.right + cg_ofst, r.top + (r.bottom - r.top - FONT_HEIGHT_SMALL) / 2 + cg_ofst, cs->abbrev, tc, SA_HOR_CENTER);
+					DrawString(r.left + cg_ofst, r.right + cg_ofst, CenterBounds(r.top, r.bottom, FONT_HEIGHT_SMALL) + cg_ofst, cs->abbrev, tc, SA_HOR_CENTER);
 				}
 				break;
 		}

src/statusbar_gui.cpp

@@ -138,7 +138,7 @@ struct StatusBarWindow : Window {
 
 	void DrawWidget(const Rect &r, int widget) const override
 	{
-		int text_offset = std::max(0, ((int)(r.bottom - r.top + 1) - FONT_HEIGHT_NORMAL) / 2); // Offset for rendering the text vertically centered
+		int text_offset = std::max(0, (r.Height() - FONT_HEIGHT_NORMAL) / 2); // Offset for rendering the text vertically centered
 		int text_top = r.top + text_offset;
 		switch (widget) {
 			case WID_S_LEFT:
@@ -190,7 +190,7 @@ struct StatusBarWindow : Window {
 
 				if (!this->reminder_timeout.HasElapsed()) {
 					Dimension icon_size = GetSpriteSize(SPR_UNREAD_NEWS);
-					DrawSprite(SPR_UNREAD_NEWS, PAL_NONE, r.right - WD_FRAMERECT_RIGHT - icon_size.width, r.top + std::max(0, ((int)(r.bottom - r.top + 1) - (int)icon_size.height) / 2));
+					DrawSprite(SPR_UNREAD_NEWS, PAL_NONE, r.right - WD_FRAMERECT_RIGHT - icon_size.width, CenterBounds(r.top, r.bottom, icon_size.height));
 				}
 				break;
 		}

src/toolbar_gui.cpp

@@ -101,18 +101,18 @@ public:
 		this->checkmark_width = GetStringBoundingBox(STR_JUST_CHECKMARK).width + 3;
 	}
 
-	uint Width() const
+	uint Width() const override
 	{
 		return DropDownListStringItem::Width() + this->checkmark_width;
 	}
 
-	void Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const
+	void Draw(const Rect &r, bool sel, Colours bg_colour) const override
 	{
 		bool rtl = _current_text_dir == TD_RTL;
 		if (this->checked) {
-			DrawString(left + WD_FRAMERECT_LEFT, right - WD_FRAMERECT_RIGHT, top, STR_JUST_CHECKMARK, sel ? TC_WHITE : TC_BLACK);
+			DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, r.top, STR_JUST_CHECKMARK, sel ? TC_WHITE : TC_BLACK);
 		}
-		DrawString(left + WD_FRAMERECT_LEFT + (rtl ? 0 : this->checkmark_width), right - WD_FRAMERECT_RIGHT - (rtl ? this->checkmark_width : 0), top, this->String(), sel ? TC_WHITE : TC_BLACK);
+		DrawString(r.left + WD_FRAMERECT_LEFT + (rtl ? 0 : this->checkmark_width), r.right - WD_FRAMERECT_RIGHT - (rtl ? this->checkmark_width : 0), r.top, this->String(), sel ? TC_WHITE : TC_BLACK);
 	}
 };
 
@@ -149,7 +149,7 @@ public:
 		return std::max(std::max(this->icon_size.height, this->lock_size.height) + 2U, (uint)FONT_HEIGHT_NORMAL);
 	}
 
-	void Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const override
+	void Draw(const Rect &r, bool sel, Colours bg_colour) const override
 	{
 		CompanyID company = (CompanyID)this->result;
 		bool rtl = _current_text_dir == TD_RTL;
@@ -157,13 +157,13 @@ public:
 		/* It's possible the company is deleted while the dropdown is open */
 		if (!Company::IsValidID(company)) return;
 
-		int icon_offset = (bottom - top - icon_size.height) / 2;
-		int text_offset = (bottom - top - FONT_HEIGHT_NORMAL) / 2;
-		int lock_offset = (bottom - top - lock_size.height) / 2;
+		int icon_y = CenterBounds(r.top, r.bottom, icon_size.height);
+		int text_y = CenterBounds(r.top, r.bottom, FONT_HEIGHT_NORMAL);
+		int lock_y = CenterBounds(r.top, r.bottom, lock_size.height);
 
-		DrawCompanyIcon(company, rtl ? right - this->icon_size.width - WD_FRAMERECT_RIGHT : left + WD_FRAMERECT_LEFT, top + icon_offset);
+		DrawCompanyIcon(company, rtl ? r.right - this->icon_size.width - WD_FRAMERECT_RIGHT : r.left + WD_FRAMERECT_LEFT, icon_y);
 		if (NetworkCompanyIsPassworded(company)) {
-			DrawSprite(SPR_LOCK, PAL_NONE, rtl ? left + WD_FRAMERECT_LEFT : right - this->lock_size.width - WD_FRAMERECT_RIGHT, top + lock_offset);
+			DrawSprite(SPR_LOCK, PAL_NONE, rtl ? r.left + WD_FRAMERECT_LEFT : r.right - this->lock_size.width - WD_FRAMERECT_RIGHT, lock_y);
 		}
 
 		SetDParam(0, company);
@@ -174,7 +174,7 @@ public:
 		} else {
 			col = sel ? TC_WHITE : TC_BLACK;
 		}
-		DrawString(left + WD_FRAMERECT_LEFT + (rtl ? 3 + this->lock_size.width : 3 + this->icon_size.width), right - WD_FRAMERECT_RIGHT - (rtl ? 3 + this->icon_size.width : 3 + this->lock_size.width), top + text_offset, STR_COMPANY_NAME_COMPANY_NUM, col);
+		DrawString(r.left + WD_FRAMERECT_LEFT + (rtl ? 3 + this->lock_size.width : 3 + this->icon_size.width), r.right - WD_FRAMERECT_RIGHT - (rtl ? 3 + this->icon_size.width : 3 + this->lock_size.width), text_y, STR_COMPANY_NAME_COMPANY_NUM, col);
 	}
 };
 

src/train_cmd.cpp

@@ -1387,20 +1387,20 @@ void GetTrainSpriteSize(EngineID engine, uint &width, uint &height, int &xoffs,
 	VehicleSpriteSeq seq;
 	GetRailIcon(engine, false, y, image_type, &seq);
 
-	Rect16 rect = seq.GetBounds();
+	Rect rect = ConvertRect<Rect16, Rect>(seq.GetBounds());
 
-	width  = UnScaleGUI(rect.right - rect.left + 1);
-	height = UnScaleGUI(rect.bottom - rect.top + 1);
+	width  = UnScaleGUI(rect.Width());
+	height = UnScaleGUI(rect.Height());
 	xoffs  = UnScaleGUI(rect.left);
 	yoffs  = UnScaleGUI(rect.top);
 
 	if (RailVehInfo(engine)->railveh_type == RAILVEH_MULTIHEAD) {
 		GetRailIcon(engine, true, y, image_type, &seq);
-		rect = seq.GetBounds();
+		rect = ConvertRect<Rect16, Rect>(seq.GetBounds());
 
 		/* Calculate values relative to an imaginary center between the two sprites. */
 		width = ScaleGUITrad(TRAININFO_DEFAULT_VEHICLE_WIDTH) + UnScaleGUI(rect.right) - xoffs;
-		height = std::max<uint>(height, UnScaleGUI(rect.bottom - rect.top + 1));
+		height = std::max<uint>(height, UnScaleGUI(rect.Height()));
 		xoffs  = xoffs - ScaleGUITrad(TRAININFO_DEFAULT_VEHICLE_WIDTH) / 2;
 		yoffs  = std::min(yoffs, UnScaleGUI(rect.top));
 	}

src/tree_gui.cpp

@@ -156,7 +156,7 @@ public:
 		if (widget >= WID_BT_TYPE_BUTTON_FIRST) {
 			const int index = widget - WID_BT_TYPE_BUTTON_FIRST;
 			/* Trees "grow" in the centre on the bottom line of the buttons */
-			DrawSprite(_tree_sprites[index].sprite, _tree_sprites[index].pal, (r.left + r.right) / 2 + WD_FRAMERECT_LEFT, r.bottom - ScaleGUITrad(BUTTON_BOTTOM_OFFSET));
+			DrawSprite(_tree_sprites[index].sprite, _tree_sprites[index].pal, CenterBounds(r.left, r.right, 0) + WD_FRAMERECT_LEFT, r.bottom - ScaleGUITrad(BUTTON_BOTTOM_OFFSET));
 		}
 	}
 

src/vehicle_gui.cpp

@@ -3167,7 +3167,7 @@ struct VehicleDetailsWindow : Window {
 				/* Draw service interval text */
 				SetDParam(0, v->GetServiceInterval());
 				SetDParam(1, v->date_of_last_service);
-				DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, r.top + (r.bottom - r.top + 1 - FONT_HEIGHT_NORMAL) / 2,
+				DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, CenterBounds(r.top, r.bottom, FONT_HEIGHT_NORMAL),
 						v->ServiceIntervalIsPercent() ? STR_VEHICLE_DETAILS_SERVICING_INTERVAL_PERCENT : STR_VEHICLE_DETAILS_SERVICING_INTERVAL_DAYS);
 				break;
 		}
@@ -3793,13 +3793,12 @@ public:
 		/* Draw the flag plus orders. */
 		bool rtl = (_current_text_dir == TD_RTL);
 		uint text_offset = std::max({GetSpriteSize(SPR_WARNING_SIGN).width, GetSpriteSize(SPR_FLAG_VEH_STOPPED).width, GetSpriteSize(SPR_FLAG_VEH_RUNNING).width}) + WD_IMGBTN_LEFT + WD_IMGBTN_RIGHT;
-		int height = r.bottom - r.top;
 		int text_left = r.left + (rtl ? (uint)WD_FRAMERECT_LEFT : text_offset);
 		int text_right = r.right - (rtl ? text_offset : (uint)WD_FRAMERECT_RIGHT);
-		int text_top = r.top + WD_FRAMERECT_TOP + (height - WD_FRAMERECT_TOP - WD_FRAMERECT_BOTTOM - FONT_HEIGHT_NORMAL) / 2;
+		int text_top = CenterBounds(r.top + WD_FRAMERECT_TOP, r.bottom - WD_FRAMERECT_BOTTOM, FONT_HEIGHT_NORMAL);
 		int image = ((v->vehstatus & VS_STOPPED) != 0) ? SPR_FLAG_VEH_STOPPED : (HasBit(v->vehicle_flags, VF_PATHFINDER_LOST)) ? SPR_WARNING_SIGN : SPR_FLAG_VEH_RUNNING;
 		int image_left = (rtl ? text_right + 1 : r.left) + WD_IMGBTN_LEFT;
-		int image_top = r.top + WD_IMGBTN_TOP + (height - WD_IMGBTN_TOP + WD_IMGBTN_BOTTOM - GetSpriteSize(image).height) / 2;
+		int image_top = CenterBounds(r.top + WD_IMGBTN_TOP, r.bottom - WD_IMGBTN_BOTTOM, GetSpriteSize(image).height);
 		int lowered = this->IsWidgetLowered(WID_VV_START_STOP) ? 1 : 0;
 		DrawSprite(image, PAL_NONE, image_left + lowered, image_top + lowered);
 		DrawString(text_left + lowered, text_right + lowered, text_top + lowered, str, text_colour, SA_HOR_CENTER);
@@ -4164,8 +4163,8 @@ int GetSingleVehicleWidth(const Vehicle *v, EngineImageType image_type)
 			bool rtl = _current_text_dir == TD_RTL;
 			VehicleSpriteSeq seq;
 			v->GetImage(rtl ? DIR_E : DIR_W, image_type, &seq);
-			Rect16 rec = seq.GetBounds();
-			return UnScaleGUI(rec.right - rec.left + 1);
+			Rect rec = ConvertRect<Rect16, Rect>(seq.GetBounds());
+			return UnScaleGUI(rec.Width());
 	}
 }
 

src/widget.cpp

@@ -401,18 +401,18 @@ static inline void DrawMatrix(const Rect &r, Colours colour, bool clicked, uint1
 	int column_width; // Width of a single column in the matrix.
 	if (num_columns == 0) {
 		column_width = resize_x;
-		num_columns = (r.right - r.left + 1) / column_width;
+		num_columns = r.Width() / column_width;
 	} else {
-		column_width = (r.right - r.left + 1) / num_columns;
+		column_width = r.Width() / num_columns;
 	}
 
 	int num_rows = GB(data, MAT_ROW_START, MAT_ROW_BITS); // Upper 8 bits of the widget data: Number of rows in the matrix.
 	int row_height; // Height of a single row in the matrix.
 	if (num_rows == 0) {
 		row_height = resize_y;
-		num_rows = (r.bottom - r.top + 1) / row_height;
+		num_rows = r.Height() / row_height;
 	} else {
-		row_height = (r.bottom - r.top + 1) / num_rows;
+		row_height = r.Height() / num_rows;
 	}
 
 	int col = _colour_gradient[colour & 0xF][6];
@@ -690,11 +690,11 @@ void DrawCaption(const Rect &r, Colours colour, Owner owner, TextColour text_col
  */
 static inline void DrawButtonDropdown(const Rect &r, Colours colour, bool clicked_button, bool clicked_dropdown, StringID str, StringAlignment align)
 {
-	int text_offset = std::max(0, ((int)(r.bottom - r.top + 1) - FONT_HEIGHT_NORMAL) / 2); // Offset for rendering the text vertically centered
+	int text_offset = std::max(0, (r.Height() - FONT_HEIGHT_NORMAL) / 2); // Offset for rendering the text vertically centered
 
 	int dd_width  = NWidgetLeaf::dropdown_dimension.width;
 	int dd_height = NWidgetLeaf::dropdown_dimension.height;
-	int image_offset = std::max(0, ((int)(r.bottom - r.top + 1) - dd_height) / 2);
+	int image_offset = std::max(0, (r.Height() - dd_height) / 2);
 
 	if (_current_text_dir == TD_LTR) {
 		DrawFrameRect(r.left, r.top, r.right - dd_width, r.bottom, colour, clicked_button ? FR_LOWERED : FR_NONE);

src/widgets/dropdown.cpp

@@ -20,14 +20,14 @@
 #include "../safeguards.h"
 
 
-void DropDownListItem::Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const
+void DropDownListItem::Draw(const Rect &r, bool sel, Colours bg_colour) const
 {
 	int c1 = _colour_gradient[bg_colour][3];
 	int c2 = _colour_gradient[bg_colour][7];
 
-	int mid = top + this->Height(0) / 2;
-	GfxFillRect(left + 1, mid - 2, right - 1, mid - 2, c1);
-	GfxFillRect(left + 1, mid - 1, right - 1, mid - 1, c2);
+	int mid = (r.top + r.bottom) / 2;
+	GfxFillRect(r.left + 1, mid - 2, r.right - 1, mid - 2, c1);
+	GfxFillRect(r.left + 1, mid - 1, r.right - 1, mid - 1, c2);
 }
 
 uint DropDownListStringItem::Width() const
@@ -37,9 +37,9 @@ uint DropDownListStringItem::Width() const
 	return GetStringBoundingBox(buffer).width;
 }
 
-void DropDownListStringItem::Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const
+void DropDownListStringItem::Draw(const Rect &r, bool sel, Colours bg_colour) const
 {
-	DrawString(left + WD_FRAMERECT_LEFT, right - WD_FRAMERECT_RIGHT, top, this->String(), (sel ? TC_WHITE : TC_BLACK) | this->colour_flags);
+	DrawString(r.left + WD_FRAMERECT_LEFT, r.right - WD_FRAMERECT_RIGHT, r.top, this->String(), (sel ? TC_WHITE : TC_BLACK) | this->colour_flags);
 }
 
 /**
@@ -85,11 +85,11 @@ uint DropDownListIconItem::Width() const
 	return DropDownListStringItem::Width() + this->dim.width + WD_FRAMERECT_LEFT;
 }
 
-void DropDownListIconItem::Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const
+void DropDownListIconItem::Draw(const Rect &r, bool sel, Colours bg_colour) const
 {
 	bool rtl = _current_text_dir == TD_RTL;
-	DrawSprite(this->sprite, this->pal, rtl ? right - this->dim.width - WD_FRAMERECT_RIGHT : left + WD_FRAMERECT_LEFT, CenterBounds(top, bottom, this->sprite_y));
-	DrawString(left + WD_FRAMERECT_LEFT + (rtl ? 0 : (this->dim.width + WD_FRAMERECT_LEFT)), right - WD_FRAMERECT_RIGHT - (rtl ? (this->dim.width + WD_FRAMERECT_RIGHT) : 0), CenterBounds(top, bottom, FONT_HEIGHT_NORMAL), this->String(), (sel ? TC_WHITE : TC_BLACK) | this->colour_flags);
+	DrawSprite(this->sprite, this->pal, rtl ? r.right - this->dim.width - WD_FRAMERECT_RIGHT : r.left + WD_FRAMERECT_LEFT, CenterBounds(r.top, r.bottom, this->sprite_y));
+	DrawString(r.left + WD_FRAMERECT_LEFT + (rtl ? 0 : (this->dim.width + WD_FRAMERECT_LEFT)), r.right - WD_FRAMERECT_RIGHT - (rtl ? (this->dim.width + WD_FRAMERECT_RIGHT) : 0), CenterBounds(r.top, r.bottom, FONT_HEIGHT_NORMAL), this->String(), (sel ? TC_WHITE : TC_BLACK) | this->colour_flags);
 }
 
 void DropDownListIconItem::SetDimension(Dimension d)
@@ -219,9 +219,9 @@ struct DropdownWindow : Window {
 	{
 		if (GetWidgetFromPos(this, _cursor.pos.x - this->left, _cursor.pos.y - this->top) < 0) return false;
 
-		NWidgetBase *nwi = this->GetWidget<NWidgetBase>(WID_DM_ITEMS);
-		int y     = _cursor.pos.y - this->top - nwi->pos_y - 2;
-		int width = nwi->current_x - 4;
+		const Rect &r = this->GetWidget<NWidgetBase>(WID_DM_ITEMS)->GetCurrentRect();
+		int y     = _cursor.pos.y - this->top - r.top - 2;
+		int width = r.Width();
 		int pos   = this->vscroll->GetPosition();
 
 		for (const auto &item : this->list) {
@@ -251,7 +251,7 @@ struct DropdownWindow : Window {
 		int y = r.top + 2;
 		int pos = this->vscroll->GetPosition();
 		for (const auto &item : this->list) {
-			int item_height = item->Height(r.right - r.left + 1);
+			int item_height = item->Height(r.Width());
 
 			/* Skip items that are scrolled up */
 			if (--pos >= 0) continue;
@@ -260,7 +260,7 @@ struct DropdownWindow : Window {
 				bool selected = (this->selected_index == item->result);
 				if (selected) GfxFillRect(r.left + 2, y, r.right - 1, y + item_height - 1, PC_BLACK);
 
-				item->Draw(r.left, r.right, y, y + item_height, selected, colour);
+				item->Draw({r.left, y, r.right, y + item_height - 1}, selected, colour);
 
 				if (item->masked) {
 					GfxFillRect(r.left + 1, y, r.right - 1, y + item_height - 1, _colour_gradient[colour][5], FILLRECT_CHECKER);
@@ -386,7 +386,7 @@ void ShowDropDownListAt(Window *w, DropDownList &&list, int selected, int button
 	int top = w->top + wi_rect.bottom + 1;
 
 	/* The preferred width equals the calling widget */
-	uint width = wi_rect.right - wi_rect.left + 1;
+	uint width = wi_rect.Width();
 
 	/* Longest item in the list, if auto_width is enabled */
 	uint max_item_width = 0;

src/widgets/dropdown_type.h

@@ -37,7 +37,7 @@ public:
 	virtual bool Selectable() const { return false; }
 	virtual uint Height(uint width) const { return FONT_HEIGHT_NORMAL; }
 	virtual uint Width() const { return 0; }
-	virtual void Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const;
+	virtual void Draw(const Rect &r, bool sel, Colours bg_colour) const;
 };
 
 /**
@@ -52,7 +52,7 @@ public:
 
 	bool Selectable() const override { return true; }
 	uint Width() const override;
-	void Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const override;
+	void Draw(const Rect &r, bool sel, Colours bg_colour) const override;
 	virtual StringID String() const { return this->string; }
 	void SetColourFlags(TextColour colour_flags) { this->colour_flags = colour_flags; }
 
@@ -98,7 +98,7 @@ public:
 
 	uint Height(uint width) const override;
 	uint Width() const override;
-	void Draw(int left, int right, int top, int bottom, bool sel, Colours bg_colour) const override;
+	void Draw(const Rect &r, bool sel, Colours bg_colour) const override;
 	void SetDimension(Dimension d);
 };
 

src/window_gui.h

@@ -170,6 +170,12 @@ enum WidgetDrawDistances {
 
 /* widget.cpp */
 void DrawFrameRect(int left, int top, int right, int bottom, Colours colour, FrameFlags flags);
+
+static inline void DrawFrameRect(const Rect &r, Colours colour, FrameFlags flags)
+{
+	DrawFrameRect(r.left, r.top, r.right, r.bottom, colour, flags);
+}
+
 void DrawCaption(const Rect &r, Colours colour, Owner owner, TextColour text_colour, StringID str, StringAlignment align);
 
 /* window.cpp */