# HG changeset patch
# User TechGeekNZ <git@tech.geek.nz>
# Date 2020-06-04 06:23:57
# Node ID 6391ca82e5606df7bbb35c86631329928949a074
# Parent  66942fe231b05c19e78085014a3f9015aee68bbc

Codechange: Realign SDL driver with SDL2 driver to ease maintenance and emphasise differences.

diff --git a/src/video/sdl2_v.cpp b/src/video/sdl2_v.cpp
--- a/src/video/sdl2_v.cpp
+++ b/src/video/sdl2_v.cpp
@@ -170,9 +170,7 @@ static void DrawSurfaceToScreen()
 	} else {
 		if (_sdl_surface != _sdl_realscreen) {
 			for (int i = 0; i < n; i++) {
-				SDL_BlitSurface(
-					_sdl_surface, &_dirty_rects[i],
-					_sdl_realscreen, &_dirty_rects[i]);
+				SDL_BlitSurface(_sdl_surface, &_dirty_rects[i], _sdl_realscreen, &_dirty_rects[i]);
 			}
 		}
 
diff --git a/src/video/sdl_v.cpp b/src/video/sdl_v.cpp
--- a/src/video/sdl_v.cpp
+++ b/src/video/sdl_v.cpp
@@ -31,7 +31,7 @@
 
 static FVideoDriver_SDL iFVideoDriver_SDL;
 
-static SDL_Surface *_sdl_screen;
+static SDL_Surface *_sdl_surface;
 static SDL_Surface *_sdl_realscreen;
 static bool _all_modes;
 
@@ -73,11 +73,11 @@ static void UpdatePalette(bool init = fa
 		pal[i].unused = 0;
 	}
 
-	SDL_SetColors(_sdl_screen, pal, _local_palette.first_dirty, _local_palette.count_dirty);
+	SDL_SetColors(_sdl_surface, pal, _local_palette.first_dirty, _local_palette.count_dirty);
 
-	if (_sdl_screen != _sdl_realscreen && init) {
+	if (_sdl_surface != _sdl_realscreen && init) {
 		/* When using a shadow surface, also set our palette on the real screen. This lets SDL
-		 * allocate as much colors (or approximations) as
+		 * allocate as many colors (or approximations) as
 		 * possible, instead of using only the default SDL
 		 * palette. This allows us to get more colors exactly
 		 * right and might allow using better approximations for
@@ -99,7 +99,7 @@ static void UpdatePalette(bool init = fa
 		SDL_SetColors(_sdl_realscreen, pal, _local_palette.first_dirty, _local_palette.count_dirty);
 	}
 
-	if (_sdl_screen != _sdl_realscreen && !init) {
+	if (_sdl_surface != _sdl_realscreen && !init) {
 		/* We're not using real hardware palette, but are letting SDL
 		 * approximate the palette during shadow -> screen copy. To
 		 * change the palette, we need to recopy the entire screen.
@@ -110,7 +110,7 @@ static void UpdatePalette(bool init = fa
 		 * best mapping of shadow palette colors to real palette
 		 * colors from scratch.
 		 */
-		SDL_BlitSurface(_sdl_screen, nullptr, _sdl_realscreen, nullptr);
+		SDL_BlitSurface(_sdl_surface, nullptr, _sdl_realscreen, nullptr);
 		SDL_UpdateRect(_sdl_realscreen, 0, 0, 0, 0);
 	}
 }
@@ -155,17 +155,20 @@ static void DrawSurfaceToScreen()
 	if (n == 0) return;
 
 	_num_dirty_rects = 0;
+
 	if (n > MAX_DIRTY_RECTS) {
-		if (_sdl_screen != _sdl_realscreen) {
-			SDL_BlitSurface(_sdl_screen, nullptr, _sdl_realscreen, nullptr);
+		if (_sdl_surface != _sdl_realscreen) {
+			SDL_BlitSurface(_sdl_surface, nullptr, _sdl_realscreen, nullptr);
 		}
+
 		SDL_UpdateRect(_sdl_realscreen, 0, 0, 0, 0);
 	} else {
-		if (_sdl_screen != _sdl_realscreen) {
+		if (_sdl_surface != _sdl_realscreen) {
 			for (int i = 0; i < n; i++) {
-				SDL_BlitSurface(_sdl_screen, &_dirty_rects[i], _sdl_realscreen, &_dirty_rects[i]);
+				SDL_BlitSurface(_sdl_surface, &_dirty_rects[i], _sdl_realscreen, &_dirty_rects[i]);
 			}
 		}
+
 		SDL_UpdateRects(_sdl_realscreen, n, _dirty_rects);
 	}
 }
@@ -308,7 +311,7 @@ bool VideoDriver_SDL::CreateMainSurface(
 	if (want_hwpalette) DEBUG(driver, 1, "SDL: requesting hardware palette");
 
 	/* Free any previously allocated shadow surface */
-	if (_sdl_screen != nullptr && _sdl_screen != _sdl_realscreen) SDL_FreeSurface(_sdl_screen);
+	if (_sdl_surface != nullptr && _sdl_surface != _sdl_realscreen) SDL_FreeSurface(_sdl_surface);
 
 	if (_sdl_realscreen != nullptr) {
 		if (_requested_hwpalette != want_hwpalette) {
@@ -375,7 +378,7 @@ bool VideoDriver_SDL::CreateMainSurface(
 	_screen.height = newscreen->h;
 	_screen.pitch = newscreen->pitch / (bpp / 8);
 	_screen.dst_ptr = newscreen->pixels;
-	_sdl_screen = newscreen;
+	_sdl_surface = newscreen;
 
 	/* When in full screen, we will always have the mouse cursor
 	 * within the window, even though SDL does not give us the
@@ -610,7 +613,7 @@ const char *VideoDriver_SDL::Start(const
 	} else if (SDL_WasInit(SDL_INIT_VIDEO) == 0) {
 		ret_code = SDL_InitSubSystem(SDL_INIT_VIDEO);
 	}
-	if (ret_code == -1) return SDL_GetError();
+	if (ret_code < 0) return SDL_GetError();
 
 	GetVideoModes();
 	if (!CreateMainSurface(_cur_resolution.width, _cur_resolution.height)) {