Auto-resize all buttons and fonts, when screen resoluition changes

src/ai/ai_gui.cpp

@@ -757,12 +757,12 @@ struct AIConfigWindow : public Window {
 	{
 		switch (widget) {
 			case WID_AIC_GAMELIST:
-				this->line_height = GetMinSizing(NWST_STEP, _settings_client.gui.min_step + WD_MATRIX_TOP + WD_MATRIX_BOTTOM);
+				this->line_height = GetMinSizing(NWST_STEP, FONT_HEIGHT_NORMAL + WD_MATRIX_TOP + WD_MATRIX_BOTTOM);
 				size->height = this->line_height;
 				break;
 
 			case WID_AIC_LIST:
-				this->line_height = GetMinSizing(NWST_STEP, _settings_client.gui.min_step + WD_MATRIX_TOP + WD_MATRIX_BOTTOM);
+				this->line_height = GetMinSizing(NWST_STEP, FONT_HEIGHT_NORMAL + WD_MATRIX_TOP + WD_MATRIX_BOTTOM);
 				size->height = 8 * this->line_height;
 				break;
 		}

src/fontcache.cpp

@@ -374,7 +374,7 @@ static void LoadFreeTypeFont(FontSize fs)
 	return;
 
 found_face:
-	new FreeTypeFontCache(fs, face, settings->size);
+	new FreeTypeFontCache(fs, face, RescaleFrom854x480(settings->size));
 }
 
 

src/gfx_func.h

@@ -45,6 +45,7 @@
 #include "gfx_type.h"
 #include "strings_type.h"
 #include "string_type.h"
+#include "core/math_func.hpp"
 
 void GameLoop();
 
@@ -196,6 +197,16 @@ static inline int Center(int top, int height, uint size = FONT_HEIGHT_NORMAL)
 	return top + (height - size) / 2;
 }
 
+/**
+ * Returns fint/button size, rescaled to current screen resolution from the base Android resolution, which is 854x480
+ * @param value The value to rescale
+ * @return Rescaled value, using lesser of the curret screen coordinates
+ */
+static inline int RescaleFrom854x480(int value)
+{
+	return min(value * _cur_resolution.width / 854, value * _cur_resolution.height / 480);
+}
+
 extern DrawPixelInfo *_cur_dpi;
 
 TextColour GetContrastColour(uint8 background);

src/network/network_content_gui.cpp

@@ -525,7 +525,7 @@ public:
 			}
 
 			case WID_NCL_MATRIX:
-				resize->height = GetMinSizing(NWST_STEP, _settings_client.gui.min_step + WD_MATRIX_TOP + WD_MATRIX_BOTTOM);
+				resize->height = GetMinSizing(NWST_STEP, FONT_HEIGHT_NORMAL + WD_MATRIX_TOP + WD_MATRIX_BOTTOM);
 				size->height = 6 * resize->height;
 				break;
 		}

src/newgrf_gui.cpp

@@ -211,7 +211,7 @@ struct NewGRFParametersWindow : public Window {
 			}
 
 			case WID_NP_BACKGROUND:
-				this->line_height = _settings_client.gui.min_step + WD_MATRIX_TOP + WD_MATRIX_BOTTOM;
+				this->line_height = FONT_HEIGHT_NORMAL + WD_MATRIX_TOP + WD_MATRIX_BOTTOM;
 
 				resize->width = 1;
 				resize->height = this->line_height;

src/settings_gui.cpp

@@ -37,6 +37,7 @@
 #include "textfile_gui.h"
 #include "stringfilter_type.h"
 #include "querystring_gui.h"
+#include "fontcache.h"
 
 
 static const StringID _driveside_dropdown[] = {
@@ -506,6 +507,29 @@ struct GameOptionsWindow : Window {
 
 			case WID_GO_RESOLUTION_DROPDOWN: // Change resolution
 				if (index < _num_resolutions && ChangeResInGame(_resolutions[index].width, _resolutions[index].height)) {
+					// Reinit all GUI elements and fonts, so they will rescale
+					InitFreeType(true);
+					CheckForMissingGlyphs();
+
+					DeleteAllNonVitalWindows();
+
+					switch (_game_mode) {
+						case GM_MENU:
+							DeleteWindowById(WC_SELECT_GAME, 0);
+							extern void ShowSelectGameWindow();
+							ShowSelectGameWindow();
+							break;
+
+						case GM_NORMAL:
+						case GM_EDITOR:
+							HideVitalWindows();
+							ShowVitalWindows();
+							break;
+
+						default:
+							break;
+					}
+
 					this->SetDirty();
 				}
 				break;

src/widget.cpp

@@ -784,6 +784,7 @@ void NWidgetResizeBase::SetMinimalSize(uint min_x, uint min_y)
 			break;
 		default: NOT_REACHED();
 	}
+	min_size = RescaleFrom854x480(min_size);
 
 	this->min_x = max(min_x, min_size);
 	this->min_y = max(min_y, min_size);
@@ -2942,6 +2943,7 @@ uint GetMinSizing(NWidSizingType type, uint min_1)
 			break;
 		default: NOT_REACHED();
 	}
+	min_sizing = RescaleFrom854x480(min_sizing);
 
 	return max(min_sizing, min_1);
 }

src/window.cpp

@@ -1822,7 +1822,7 @@ void CheckWindowMinSizings()
 	SETTING_BUTTON_WIDTH  = 2 * SETTING_BUTTON_HEIGHT;
 
 	extern uint _tooltip_width;
-	_tooltip_width = max<uint>(194, 10 * _settings_client.gui.min_button);
+	_tooltip_width = max<uint>(194, 10 * RescaleFrom854x480(_settings_client.gui.min_button));
 }
 
 /**