From 3b7f41e2bb6fbe16bb0b3d3dfd82b86cf3a5628f Mon Sep 17 00:00:00 2001
From: terminx <terminx@1a8010ca-5511-0410-912e-c29ae57300e0>
Date: Sun, 18 Nov 2018 18:11:38 +0000
Subject: [PATCH] sdlayer: pass SDL_WINDOW_FULLSCREEN_DESKTOP to
 SDL_SetWindowFullscreen() when setting a windowed mode that matches the
 desktop resolution

git-svn-id: https://svn.eduke32.com/eduke32@7204 1a8010ca-5511-0410-912e-c29ae57300e0
---
 source/build/src/sdlayer.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/source/build/src/sdlayer.cpp b/source/build/src/sdlayer.cpp
index af3e75f3c..009447341 100644
--- a/source/build/src/sdlayer.cpp
+++ b/source/build/src/sdlayer.cpp
@@ -1539,6 +1539,11 @@ int32_t videoSetMode(int32_t x, int32_t y, int32_t c, int32_t fs)
 
     initprintf("Setting video mode %dx%d (%d-bpp %s)\n", x, y, c, ((fs & 1) ? "fullscreen" : "windowed"));
 
+    SDL_DisplayMode desktopmode;
+    SDL_GetDesktopDisplayMode(0, &desktopmode);
+
+    int const windowedMode = (desktopmode.w == x && desktopmode.h == y) ? SDL_WINDOW_FULLSCREEN_DESKTOP : 0;
+
 #ifdef USE_OPENGL
     if (c > 8 || !nogl)
     {
@@ -1600,7 +1605,7 @@ int32_t videoSetMode(int32_t x, int32_t y, int32_t c, int32_t fs)
                 return -1;
             }
 
-            SDL_SetWindowFullscreen(sdl_window, ((fs & 1) ? SDL_WINDOW_FULLSCREEN : 0));
+            SDL_SetWindowFullscreen(sdl_window, ((fs & 1) ? SDL_WINDOW_FULLSCREEN : windowedMode));
             SDL_GL_SetSwapInterval(vsync_renderlayer);
 
             setrefreshrate();
@@ -1625,7 +1630,7 @@ int32_t videoSetMode(int32_t x, int32_t y, int32_t c, int32_t fs)
                 SDL2_VIDEO_ERR("SDL_GetWindowSurface");
         }
 
-        SDL_SetWindowFullscreen(sdl_window, ((fs & 1) ? SDL_WINDOW_FULLSCREEN : 0));
+        SDL_SetWindowFullscreen(sdl_window, ((fs & 1) ? SDL_WINDOW_FULLSCREEN : windowedMode));
     }
 
     SDL_SetHint(SDL_HINT_VIDEO_HIGHDPI_DISABLED, "1");