Bug #23908 - Don't hold copies of the window surface

Change more copies of the window surface to be references
instead. This will make sure they do not contain a stale version that
has a pointer that points to freed memory.

src/attack_prediction_display.cpp

@@ -344,7 +344,7 @@ void battle_prediction_pane::draw_unit(int x_off, int damage_line_skip, int left
 									   const std::string& label, int label_width,
 									   surface& hp_distrib, int hp_distrib_width)
 {
-	surface screen = resources::screen->get_screen_surface();
+	surface& screen = resources::screen->get_screen_surface();
 	int i;
 
 	// NOTE. A preview pane is not made to be used alone and it is not

src/display.cpp

@@ -1336,7 +1336,7 @@ void display::drawing_buffer_commit()
 	GPU_UnsetClip(get_render_target());
 #else
 	SDL_Rect clip_rect = map_area();
-	surface screen = get_screen_surface();
+	surface& screen = get_screen_surface();
 	clip_rect_setter set_clip_rect(screen, &clip_rect);
 
 	/*
@@ -1833,7 +1833,7 @@ void display::draw_init()
 #ifdef SDL_GPU
 		draw_background(screen_, clip_rect, theme_.border().background_image);
 #else
-		const surface screen = get_screen_surface();
+		const surface& screen = get_screen_surface();
 		clip_rect_setter set_clip_rect(screen, &clip_rect);
 		draw_background(screen, clip_rect, theme_.border().background_image);
 #endif
@@ -2791,7 +2791,7 @@ const SDL_Rect& display::get_clip_rect()
 void display::draw_invalidated() {
 //	log_scope("display::draw_invalidated");
 	SDL_Rect clip_rect = get_clip_rect();
-	surface screen = get_screen_surface();
+	surface& screen = get_screen_surface();
 	clip_rect_setter set_clip_rect(screen, &clip_rect);
 	BOOST_FOREACH(const map_location& loc, invalidated_) {
 		int xpos = get_location_x(loc);

src/display.hpp

@@ -205,7 +205,7 @@ public:
 	CVideo& video() { return screen_; }
 
 	/** return the screen surface or the surface used for map_screenshot. */
-	surface get_screen_surface() { return map_screenshot_ ? map_screenshot_surf_ : screen_.getSurface();}
+	surface& get_screen_surface() { return map_screenshot_ ? map_screenshot_surf_ : screen_.getSurface();}
 
 	virtual bool in_game() const { return false; }
 	virtual bool in_editor() const { return false; }

src/font.cpp

@@ -885,7 +885,7 @@ surface get_rendered_text(const std::string& str, int size, const SDL_Color& col
 	return render_text(str, size, color, style, false);
 }
 
-SDL_Rect draw_text_line(surface gui_surface, const SDL_Rect& area, int size,
+SDL_Rect draw_text_line(surface& gui_surface, const SDL_Rect& area, int size,
 		   const SDL_Color& color, const std::string& text,
 		   int x, int y, bool use_tooltips, int style)
 {

src/font.hpp

@@ -76,7 +76,7 @@ inline int relative_size(int size)
 // Returns a SDL surface containing the text rendered in a given color.
 surface get_rendered_text(const std::string& text, int size, const SDL_Color& color, int style=0);
 
-SDL_Rect draw_text_line(surface gui_surface, const SDL_Rect& area, int size,
+SDL_Rect draw_text_line(surface& gui_surface, const SDL_Rect& area, int size,
 						const SDL_Color& color, const std::string& text,
 						int x, int y, bool use_tooltips, int style);
 

src/game_initialization/multiplayer_create.cpp

@@ -557,7 +557,7 @@ void create::draw_level_image()
 		draw_centered_on_background(image, image_rect_, back_color,
 			video().getSurface());
 	} else {
-		surface display(disp_.get_screen_surface());
+		surface& display(disp_.get_screen_surface());
 		sdl::fill_rect(display, &image_rect_,
 			SDL_MapRGB(display->format, 0, 0, 0));
 		update_rect(image_rect_);

src/halo.cpp

@@ -232,7 +232,7 @@ bool halo_impl::effect::render()
 		return false;
 	}
 
-	surface screen = disp->get_screen_surface();
+	surface& screen = disp->get_screen_surface();
 
 	const clip_rect_setter clip_setter(screen, &clip_rect);
 	if(buffer_ == NULL || buffer_->w != rect.w || buffer_->h != rect.h) {
@@ -265,7 +265,7 @@ void halo_impl::effect::unrender()
 		return;
 	}
 
-	surface screen = disp->get_screen_surface();
+	surface& screen = disp->get_screen_surface();
 
 	SDL_Rect clip_rect = disp->map_outside_area();
 	const clip_rect_setter clip_setter(screen, &clip_rect);

src/marked-up_text.cpp

@@ -190,7 +190,7 @@ SDL_Rect text_area(const std::string& text, int size, int style)
 	return draw_text(NULL, area, size, font::NORMAL_COLOR, text, 0, 0, false, style);
 }
 
-SDL_Rect draw_text(surface dst, const SDL_Rect& area, int size,
+SDL_Rect draw_text(surface& dst, const SDL_Rect& area, int size,
                    const SDL_Color& color, const std::string& txt,
                    int x, int y, bool use_tooltips, int style)
 {
@@ -241,7 +241,9 @@ SDL_Rect draw_text(CVideo* gui, const SDL_Rect& area, int size,
                    const SDL_Color& color, const std::string& txt,
                    int x, int y, bool use_tooltips, int style)
 {
-	return draw_text(gui != NULL ? gui->getSurface() : NULL, area, size, color, txt, x, y, use_tooltips, style);
+	surface null_surf = surface(NULL);
+
+	return draw_text(gui != NULL ? gui->getSurface() : null_surf, area, size, color, txt, x, y, use_tooltips, style);
 }
 
 bool is_format_char(char c)

src/marked-up_text.hpp

@@ -76,7 +76,7 @@ std::string::const_iterator parse_markup(std::string::const_iterator i1,
  * A bounding rectangle of the text is returned. If dst is NULL, then the
  * text will not be drawn, and a bounding rectangle only will be returned.
  */
-SDL_Rect draw_text(surface dst, const SDL_Rect& area, int size,
+SDL_Rect draw_text(surface& dst, const SDL_Rect& area, int size,
                    const SDL_Color& color, const std::string& text,
                    int x, int y, bool use_tooltips = false, int style = 0);