From e565c26d23694783974b5b8a971213e24a820654 Mon Sep 17 00:00:00 2001
From: fgsfds <pvt.fgsfds@gmail.com>
Date: Wed, 19 Feb 2020 03:34:42 +0300
Subject: [PATCH] SDL: separated GL loading code

---
 src/game/sdl/g_system.pas  | 38 +++++++++++++++++++++++++++-----------
 src/game/sdl2/g_system.pas | 38 +++++++++++++++++++++++++++-----------
 2 files changed, 54 insertions(+), 22 deletions(-)

diff --git a/src/game/sdl/g_system.pas b/src/game/sdl/g_system.pas
index bba2cae..b866972 100644
--- a/src/game/sdl/g_system.pas
+++ b/src/game/sdl/g_system.pas
@@ -24,6 +24,7 @@ interface
   procedure sys_Delay (ms: Integer);
 
   (* --- Graphics --- *)
+  function sys_LoadGL: Boolean;
   function sys_GetDisplayModes (bpp: Integer): SSArray;
   function sys_SetDisplayMode (w, h, bpp: Integer; fullscreen, maximized: Boolean): Boolean;
   procedure sys_EnableVSync (yes: Boolean);
@@ -70,6 +71,28 @@ implementation
 
   (* --------- Graphics --------- *)
 
+  function LoadGL: Boolean;
+  begin
+    result := true;
+    {$IFDEF NOGL_INIT}
+    nogl_Init;
+    if glRenderToFBO and (not nogl_ExtensionSupported('GL_OES_framebuffer_object')) then
+    {$ELSE}
+    if glRenderToFBO and (not Load_GL_ARB_framebuffer_object) then
+    {$ENDIF}
+    begin
+      e_LogWriteln('GL: framebuffer objects not supported; disabling FBO rendering');
+      glRenderToFBO := false;
+    end;
+  end;
+
+  procedure FreeGL;
+  begin
+    {$IFDEF NOGL_INIT}
+    nogl_Quit();
+    {$ENDIF}
+  end;
+
   procedure UpdateSize (w, h: Integer);
   begin
     gWinSizeX := w;
@@ -125,15 +148,10 @@ implementation
       screen := SDL_SetVideoMode(w, h, bpp, flags);
       if screen <> nil then
       begin
-        {$IFDEF NOGL_INIT}
-        nogl_Init;
-        if glRenderToFBO and (not nogl_ExtensionSupported('GL_OES_framebuffer_object')) then
-        {$ELSE}
-        if glRenderToFBO and (not Load_GL_ARB_framebuffer_object()) then
-        {$ENDIF}
+        if not LoadGL then
         begin
-          e_LogWriteln('SDL: no framebuffer object support detected');
-          glRenderToFBO := False
+          e_LogWriteln('GL: unable to load OpenGL functions', TMsgType.Fatal);
+          exit;
         end;
         SDL_WM_SetCaption(GetTitle(), nil);
         gFullScreen := fullscreen;
@@ -497,9 +515,7 @@ implementation
       RemoveJoystick(i);
     if screen <> nil then
     begin
-      {$IFDEF NOGL_INIT}
-        nogl_Quit;
-      {$ENDIF}
+      FreeGL;
       SDL_FreeSurface(screen)
     end;
     SDL_Quit
diff --git a/src/game/sdl2/g_system.pas b/src/game/sdl2/g_system.pas
index 29a81b0..31c5b1c 100644
--- a/src/game/sdl2/g_system.pas
+++ b/src/game/sdl2/g_system.pas
@@ -74,6 +74,28 @@ implementation
 
   (* --------- Graphics --------- *)
 
+  function LoadGL: Boolean;
+  begin
+    result := true;
+    {$IFDEF NOGL_INIT}
+    nogl_Init;
+    if glRenderToFBO and (not nogl_ExtensionSupported('GL_OES_framebuffer_object')) then
+    {$ELSE}
+    if glRenderToFBO and (not Load_GL_ARB_framebuffer_object) then
+    {$ENDIF}
+    begin
+      e_LogWriteln('GL: framebuffer objects not supported; disabling FBO rendering');
+      glRenderToFBO := false;
+    end;
+  end;
+
+  procedure FreeGL;
+  begin
+    {$IFDEF NOGL_INIT}
+    nogl_Quit();
+    {$ENDIF}
+  end;
+
   procedure UpdateSize (w, h: Integer);
   begin
     gWinSizeX := w;
@@ -156,15 +178,11 @@ implementation
         context := SDL_GL_CreateContext(window);
         if context <> nil then
         begin
-          {$IFDEF NOGL_INIT}
-          nogl_Init;
-          if glRenderToFBO and (not nogl_ExtensionSupported('GL_OES_framebuffer_object')) then
-          {$ELSE}
-          if glRenderToFBO and (not Load_GL_ARB_framebuffer_object()) then
-          {$ENDIF}
+          if not LoadGL then
           begin
-            e_LogWriteln('SDL: no framebuffer object support detected');
-            glRenderToFBO := False
+            e_LogWriteln('GL: unable to load OpenGL functions', TMsgType.Fatal);
+            SDL_GL_DeleteContext(context); context := nil;
+            exit;
           end;
           if (fullscreen = false) and (maximized = false) and (wc = false) then
           begin
@@ -564,9 +582,7 @@ implementation
     e_WriteLog('Releasing SDL2', TMsgType.Notify);
     if context <> nil then
     begin
-      {$IFDEF NOGL_INIT}
-        nogl_Quit;
-      {$ENDIF}
+      FreeGL;
       SDL_GL_DeleteContext(context);
       context := nil;
     end;
-- 
2.29.2