SDL now automatically resizes the window upon loading a ROM if it was not manually resized by the user

SDL/gui.c

@@ -45,6 +45,8 @@ static unsigned factor;
 
 static SDL_Surface *converted_background = NULL;
 
+bool screen_manually_resized = false;
+
 void render_texture(void *pixels,  void *previous)
 {
     if (renderer) {
@@ -1253,6 +1255,7 @@ static void cycle_scaling_backwards(unsigned index)
     }
     update_viewport();
     render_texture(NULL, NULL);
+    screen_manually_resized = false;
 }
 
 static void cycle_default_scale(unsigned index)
@@ -1266,6 +1269,7 @@ static void cycle_default_scale(unsigned index)
 
     rescale_window();
     update_viewport();
+    screen_manually_resized = false;
 }
 
 static void cycle_default_scale_backwards(unsigned index)
@@ -1279,6 +1283,7 @@ static void cycle_default_scale_backwards(unsigned index)
 
     rescale_window();
     update_viewport();
+    screen_manually_resized = false;
 }
 
 static void cycle_color_correction(unsigned index)
@@ -2485,6 +2490,7 @@ void run_gui(bool is_running)
                 if (event.window.event == SDL_WINDOWEVENT_RESIZED) {
                     update_viewport();
                     render_texture(NULL, NULL);
+                    screen_manually_resized = true;
                 }
                 if (event.window.type == SDL_WINDOWEVENT_MOVED
 #if SDL_COMPILEDVERSION > 2018
@@ -2639,6 +2645,7 @@ void run_gui(bool is_running)
                     }
                     update_swap_interval();
                     update_viewport();
+                    screen_manually_resized = true;
                 }
                 else if (event_hotkey_code(&event) == SDL_SCANCODE_O) {
                     if (event.key.keysym.mod & MODIFIER) {

SDL/gui.h

@@ -45,6 +45,7 @@ enum pending_command {
 extern enum pending_command pending_command;
 extern unsigned command_parameter;
 extern char *dropped_state_file;
+extern bool screen_manually_resized;
 
 void update_viewport(void);
 void run_gui(bool is_running);

SDL/main.c

@@ -133,6 +133,7 @@ retry: {
                 
             case SDL_WINDOWEVENT: {
                 if (event.window.event == SDL_WINDOWEVENT_SIZE_CHANGED) {
+                    screen_manually_resized = true;
                     update_viewport();
                 }
                 if (event.window.type == SDL_WINDOWEVENT_MOVED
@@ -312,6 +313,7 @@ static void handle_events(GB_gameboy_t *gb)
                 
             case SDL_WINDOWEVENT: {
                 if (event.window.event == SDL_WINDOWEVENT_SIZE_CHANGED) {
+                    screen_manually_resized = true;
                     update_viewport();
                 }
                 if (event.window.type == SDL_WINDOWEVENT_MOVED
@@ -556,6 +558,7 @@ static void handle_events(GB_gameboy_t *gb)
                             }
                             update_swap_interval();
                             update_viewport();
+                            screen_manually_resized = true;
                         }
                         break;
                         
@@ -1035,8 +1038,16 @@ static void run(void)
     pending_command = GB_SDL_NO_COMMAND;
 restart:;
     model = model_to_use();
+    bool should_resize = !screen_manually_resized;
+    signed current_window_width, current_window_height;
+    SDL_GetWindowSize(window, &current_window_width, &current_window_height);
+
     
     if (GB_is_inited(&gb)) {
+        should_resize =
+            current_window_width == GB_get_screen_width(&gb) * configuration.default_scale &&
+            current_window_height == GB_get_screen_height(&gb) * configuration.default_scale;
+        
         if (doing_hot_swap) {
             doing_hot_swap = false;
         }
@@ -1107,6 +1118,15 @@ restart:;
         GB_switch_model_and_reset(&gb, model);
     }
     
+    if (should_resize) {
+        signed width = GB_get_screen_width(&gb) * configuration.default_scale;
+        signed height = GB_get_screen_height(&gb) * configuration.default_scale;
+        signed x, y;
+        SDL_GetWindowPosition(window, &x, &y);
+        SDL_SetWindowSize(window, width, height);
+        SDL_SetWindowPosition(window, x - (width - current_window_width) / 2, y - (height - current_window_height) / 2);
+    }
+    
     /* Configure battery */
     char battery_save_path[path_length + 5]; /* At the worst case, size is strlen(path) + 4 bytes for .sav + NULL */
     replace_extension(filename, path_length, battery_save_path, ".sav");
@@ -1417,7 +1437,9 @@ int main(int argc, char **argv)
                 configuration.allow_background_controllers? "1" : "0");
 
     window = SDL_CreateWindow("SameBoy v" GB_VERSION, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
-                              160 * configuration.default_scale, 144 * configuration.default_scale, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI);
+                              (configuration.border_mode == GB_BORDER_ALWAYS? 256 : 160) * configuration.default_scale,
+                              (configuration.border_mode == GB_BORDER_ALWAYS? 224 : 144) * configuration.default_scale,
+                              SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI);
     if (window == NULL) {
         fputs(SDL_GetError(), stderr);
         exit(1);