From 2e622547c5b693ea81ab5ea30653824a0f8096f9 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@libsdl.org>
Date: Sat, 24 Jun 2006 02:48:55 +0000
Subject: [PATCH] Merged SDL_GL_SWAP_CONTROL fix from SDL 1.2

---
 src/video/wincommon/SDL_wingl.c | 33 ++++++++++++++++++++++++---------
 src/video/x11/SDL_x11gl.c       |  7 +++++--
 test/testgl.c                   |  2 +-
 3 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/src/video/wincommon/SDL_wingl.c b/src/video/wincommon/SDL_wingl.c
index 783b9e564..85d60b13b 100644
--- a/src/video/wincommon/SDL_wingl.c
+++ b/src/video/wincommon/SDL_wingl.c
@@ -150,8 +150,8 @@ Init_WGL_ARB_extensions(_THIS)
         this->gl_data->wglChoosePixelFormatARB = (BOOL(WINAPI *)
                                                   (HDC, const int *,
                                                    const FLOAT *, UINT, int *,
-                                                   UINT *)) this->gl_data->
-            wglGetProcAddress("wglChoosePixelFormatARB");
+                                                   UINT *))
+            this->gl_data->wglGetProcAddress("wglChoosePixelFormatARB");
         this->gl_data->wglGetPixelFormatAttribivARB =
             (BOOL(WINAPI *) (HDC, int, int, UINT, const int *, int *))
             this->gl_data->wglGetProcAddress("wglGetPixelFormatAttribivARB");
@@ -357,7 +357,12 @@ WIN_GL_SetupWindow(_THIS)
         /* Uh oh, something is seriously wrong here... */
         wglext = NULL;
     }
-    if (!wglext || !SDL_strstr(wglext, "WGL_EXT_swap_control")) {
+    if (wglext && SDL_strstr(wglext, "WGL_EXT_swap_control")) {
+        this->gl_data->wglSwapIntervalEXT =
+            WIN_GL_GetProcAddress(this, "wglSwapIntervalEXT");
+        this->gl_data->wglGetSwapIntervalEXT =
+            WIN_GL_GetProcAddress(this, "wglGetSwapIntervalEXT");
+    } else {
         this->gl_data->wglSwapIntervalEXT = NULL;
         this->gl_data->wglGetSwapIntervalEXT = NULL;
     }
@@ -470,9 +475,8 @@ WIN_GL_GetAttribute(_THIS, SDL_GLattr attrib, int *value)
             break;
         case SDL_GL_ACCELERATED_VISUAL:
             wgl_attrib = WGL_ACCELERATION_ARB;
-            this->gl_data->wglGetPixelFormatAttribivARB(GL_hdc,
-                                                        pixel_format, 0,
-                                                        1, &wgl_attrib,
+            this->gl_data->wglGetPixelFormatAttribivARB(GL_hdc, pixel_format,
+                                                        0, 1, &wgl_attrib,
                                                         value);
             if (*value == WGL_NO_ACCELERATION_ARB) {
                 *value = SDL_FALSE;
@@ -483,15 +487,17 @@ WIN_GL_GetAttribute(_THIS, SDL_GLattr attrib, int *value)
             break;
         case SDL_GL_SWAP_CONTROL:
             if (this->gl_data->wglGetSwapIntervalEXT) {
-                return this->gl_data->wglGetSwapIntervalEXT();
+                *value = this->gl_data->wglGetSwapIntervalEXT();
+                return 0;
             } else {
                 return -1;
             }
+            break;
         default:
             return (-1);
         }
-        this->gl_data->wglGetPixelFormatAttribivARB(GL_hdc, pixel_format,
-                                                    0, 1, &wgl_attrib, value);
+        this->gl_data->wglGetPixelFormatAttribivARB(GL_hdc, pixel_format, 0,
+                                                    1, &wgl_attrib, value);
 
         return 0;
     }
@@ -551,6 +557,14 @@ WIN_GL_GetAttribute(_THIS, SDL_GLattr attrib, int *value)
     case SDL_GL_MULTISAMPLESAMPLES:
         *value = 1;
         break;
+    case SDL_GL_SWAP_CONTROL:
+        if (this->gl_data->wglGetSwapIntervalEXT) {
+            *value = this->gl_data->wglGetSwapIntervalEXT();
+            return 0;
+        } else {
+            return -1;
+        }
+        break;
     default:
         retval = -1;
         break;
@@ -653,4 +667,5 @@ WIN_GL_GetProcAddress(_THIS, const char *proc)
 }
 
 #endif /* SDL_VIDEO_OPENGL */
+
 /* vi: set ts=4 sw=4 expandtab: */
diff --git a/src/video/x11/SDL_x11gl.c b/src/video/x11/SDL_x11gl.c
index 25e59f79c..f049857d8 100644
--- a/src/video/x11/SDL_x11gl.c
+++ b/src/video/x11/SDL_x11gl.c
@@ -411,9 +411,10 @@ X11_GL_GetAttribute(_THIS, SDL_GLattr attrib, int *value)
         break;
     case SDL_GL_SWAP_CONTROL:
         if (this->gl_data->glXGetSwapIntervalMESA) {
-            return this->gl_data->glXGetSwapIntervalMESA();
+            *value = this->gl_data->glXGetSwapIntervalMESA();
+            return (0);
         } else {
-            return (-1) /*(this->gl_config.swap_control > 0) */ ;
+            return (-1);
         }
         break;
     default:
@@ -567,3 +568,5 @@ X11_GL_GetProcAddress(_THIS, const char *proc)
 }
 
 #endif /* SDL_VIDEO_OPENGL_GLX */
+
+/* vi: set ts=4 sw=4 expandtab: */
diff --git a/test/testgl.c b/test/testgl.c
index a5a5c9bec..6b3254647 100644
--- a/test/testgl.c
+++ b/test/testgl.c
@@ -746,7 +746,7 @@ main(int argc, char *argv[])
         }
         if (strncmp(argv[i], "-h", 2) == 0) {
             printf
-                ("Usage: %s [-twice] [-logo] [-logocursor] [-slow] [-bpp n] [-gamma n] [-noframe] [-fsaa] [-fullscreen]\n",
+                ("Usage: %s [-twice] [-logo] [-logocursor] [-slow] [-bpp n] [-gamma n] [-noframe] [-fsaa] [-accel] [-sync] [-fullscreen]\n",
                  argv[0]);
             exit(0);
         }