From 370b9650cf297c449f4831d9870597d8abdba760 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <icculus@icculus.org>
Date: Sat, 13 Apr 2013 00:15:23 -0400
Subject: [PATCH] Implemented SDL_GL_[GS]etAttribute().

---
 src/SDL12_compat.c | 68 ++++++++++++++++++++++++++++++++++++++++++++--
 src/SDL20_syms.h   |  2 ++
 2 files changed, 67 insertions(+), 3 deletions(-)

diff --git a/src/SDL12_compat.c b/src/SDL12_compat.c
index e52a1529b..0d032ba9b 100644
--- a/src/SDL12_compat.c
+++ b/src/SDL12_compat.c
@@ -36,8 +36,6 @@
 //#include "render/SDL_yuv_sw_c.h"
 
 // !!! IMPLEMENT_ME SDL_ConvertSurface
-// !!! IMPLEMENT_ME SDL_GL_GetAttribute
-// !!! IMPLEMENT_ME SDL_GL_SetAttribute
 // !!! IMPLEMENT_ME SDL_GetKeyName
 // !!! IMPLEMENT_ME SDL_GetKeyState
 // !!! IMPLEMENT_ME SDL_GetModState
@@ -312,6 +310,27 @@ typedef struct
     SDL_Cursor *wm_cursor;  /* the real SDL 1.2 has an opaque pointer to a platform-specific cursor here. */
 } SDL12_Cursor;
 
+typedef enum
+{
+    SDL12_GL_RED_SIZE,
+    SDL12_GL_GREEN_SIZE,
+    SDL12_GL_BLUE_SIZE,
+    SDL12_GL_ALPHA_SIZE,
+    SDL12_GL_BUFFER_SIZE,
+    SDL12_GL_DOUBLEBUFFER,
+    SDL12_GL_DEPTH_SIZE,
+    SDL12_GL_STENCIL_SIZE,
+    SDL12_GL_ACCUM_RED_SIZE,
+    SDL12_GL_ACCUM_GREEN_SIZE,
+    SDL12_GL_ACCUM_BLUE_SIZE,
+    SDL12_GL_ACCUM_ALPHA_SIZE,
+    SDL12_GL_STEREO,
+    SDL12_GL_MULTISAMPLEBUFFERS,
+    SDL12_GL_MULTISAMPLESAMPLES,
+    SDL12_GL_ACCELERATED_VISUAL,
+    SDL12_GL_SWAP_CONTROL,
+    SDL12_GL_MAX_ATTRIBUTE
+} SDL12_GLattr;
 
 static SDL12_VideoInfo VideoInfo;
 static SDL_Window *VideoWindow20 = NULL;
@@ -331,7 +350,7 @@ static int CDRomInit = 0;
 static SDL12_EventFilter EventFilter12 = NULL;
 static SDL12_Cursor *CurrentCursor = NULL;
 static Uint8 EventStates[SDL12_NUMEVENTS];
-
+static int SwapInterval = 0;
 
 // !!! FIXME: need a mutex for the event queue.
 #define SDL12_MAXEVENTS 128
@@ -466,6 +485,7 @@ DoSDLInit(const int justsubs, Uint32 sdl12flags)
         EventStates[SDL12_SYSWMEVENT] = SDL_IGNORE;  /* off by default. */
         SDL20_SetEventFilter(EventFilter20to12, NULL);
         VideoDisplayIndex = GetVideoDisplay();
+        SwapInterval = 0;
     }
 
     return rc;
@@ -1548,6 +1568,9 @@ SDL_SetVideoMode(int width, int height, int bpp, Uint32 flags12)
         if (SDL_GL_MakeCurrent(VideoWindow20, VideoContext) < 0) {
             return NULL;
         }
+
+        SDL_GL_SetSwapInterval(SwapInterval);  /* don't care if this fails. */
+
         VideoSurface =
             SDL_CreateRGBSurfaceFrom(NULL, width, height, bpp, 0, 0, 0, 0, 0);
         if (!VideoSurface) {
@@ -2687,6 +2710,45 @@ SDL_FreeYUVOverlay(SDL_Overlay * overlay)
     SDL_free(overlay);
 }
 
+int
+SDL_GL_SetAttribute(SDL12_GLattr attr, int value)
+{
+    if (attr >= SDL12_GL_MAX_ATTRIBUTE)
+    {
+        SDL_SetError("Unknown GL attribute");
+        return -1;
+    }
+
+    /* swap control was moved out of this API, everything else lines up. */
+    if (attr == SDL12_GL_SWAP_CONTROL)
+    {
+        SwapInterval = value;
+        return 0;
+    }
+
+    return SDL20_GL_SetAttribute((SDL_GLattr) attr, value);
+}
+
+int
+SDL_GL_GetAttribute(SDL12_GLattr attr, int* value)
+{
+    if (attr >= SDL12_GL_MAX_ATTRIBUTE)
+    {
+        SDL_SetError("Unknown GL attribute");
+        return -1;
+    }
+
+    /* swap control was moved out of this API, everything else lines up. */
+    if (attr == SDL12_GL_SWAP_CONTROL)
+    {
+        *value = SDL20_GL_GetSwapInterval();
+        return 0;
+    }
+
+    return SDL20_GL_GetAttribute((SDL_GLattr) attr, value);
+}
+
+
 void
 SDL_GL_SwapBuffers(void)
 {
diff --git a/src/SDL20_syms.h b/src/SDL20_syms.h
index 935824ff0..ffb897ed7 100644
--- a/src/SDL20_syms.h
+++ b/src/SDL20_syms.h
@@ -45,6 +45,8 @@ SDL20_SYM(SDL_Surface*,LoadBMP_RW,(SDL_RWops *a, int b),(a,b),return)
 SDL20_SYM(int,SaveBMP_RW,(SDL_Surface *a, SDL_RWops *b, int c),(a,b,c),return)
 SDL20_SYM_PASSTHROUGH(int,GL_LoadLibrary,(const char *a),(a),return)
 SDL20_SYM_PASSTHROUGH(void *,GL_GetProcAddress,(const char *a),(a),return)
+SDL20_SYM(int,GL_SetAttribute,(SDL_GLattr a, int b),(a,b),return)
+SDL20_SYM(int,GL_GetAttribute,(SDL_GLattr a, int *b),(a,b),return)
 SDL20_SYM(void,GetClipRect,(SDL_Surface *a, SDL_Rect *b),(a,b),)
 SDL20_SYM(SDL_bool,SetClipRect,(SDL_Surface *a, const SDL_Rect *b),(a,b),return)
 SDL20_SYM(int,FillRect,(SDL_Surface *a,const SDL_Rect *b,Uint32 c),(a,b,c),return)