WinRT: enabled OpenGL ES 2 support on Windows Phone

The "future-dev" branch of MSOpenTech's ANGLE/WinRT repository (at
https://github.com/msopentech/angle) includes support for Windows Phone 8.1.
This change allows it to be used in conjunction with SDL's OpenGL functions.

VisualC-WinRT/WinPhone80_VS2012/SDL-WinPhone80.vcxproj

@@ -237,6 +237,8 @@
     <ClInclude Include="..\..\src\joystick\windows\SDL_xinputjoystick_c.h" />
     <ClInclude Include="..\..\src\render\direct3d11\SDL_render_winrt.h" />
     <ClInclude Include="..\..\src\render\mmx.h" />
+    <ClInclude Include="..\..\src\render\opengles2\SDL_gles2funcs.h" />
+    <ClInclude Include="..\..\src\render\opengles2\SDL_shaders_gles2.h" />
     <ClInclude Include="..\..\src\render\SDL_d3dmath.h" />
     <ClInclude Include="..\..\src\render\SDL_sysrender.h" />
     <ClInclude Include="..\..\src\render\SDL_yuv_sw_c.h" />
@@ -264,6 +266,7 @@
     <ClInclude Include="..\..\src\video\SDL_blit_auto.h" />
     <ClInclude Include="..\..\src\video\SDL_blit_copy.h" />
     <ClInclude Include="..\..\src\video\SDL_blit_slow.h" />
+    <ClInclude Include="..\..\src\video\SDL_egl_c.h" />
     <ClInclude Include="..\..\src\video\SDL_pixels_c.h" />
     <ClInclude Include="..\..\src\video\SDL_rect_c.h" />
     <ClInclude Include="..\..\src\video\SDL_RLEaccel_c.h" />
@@ -272,6 +275,7 @@
     <ClInclude Include="..\..\src\video\winrt\SDL_winrtevents_c.h" />
     <ClInclude Include="..\..\src\video\winrt\SDL_winrtmessagebox.h" />
     <ClInclude Include="..\..\src\video\winrt\SDL_winrtmouse_c.h" />
+    <ClInclude Include="..\..\src\video\winrt\SDL_winrtopengles.h" />
     <ClInclude Include="..\..\src\video\winrt\SDL_winrtvideo_cpp.h" />
   </ItemGroup>
   <ItemGroup>
@@ -345,6 +349,8 @@
       <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</CompileAsWinRT>
       <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</CompileAsWinRT>
     </ClCompile>
+    <ClCompile Include="..\..\src\render\opengles2\SDL_render_gles2.c" />
+    <ClCompile Include="..\..\src\render\opengles2\SDL_shaders_gles2.c" />
     <ClCompile Include="..\..\src\render\SDL_d3dmath.c" />
     <ClCompile Include="..\..\src\render\SDL_render.c" />
     <ClCompile Include="..\..\src\render\SDL_yuv_mmx.c" />
@@ -387,6 +393,7 @@
     <ClCompile Include="..\..\src\video\SDL_blit_slow.c" />
     <ClCompile Include="..\..\src\video\SDL_bmp.c" />
     <ClCompile Include="..\..\src\video\SDL_clipboard.c" />
+    <ClCompile Include="..\..\src\video\SDL_egl.c" />
     <ClCompile Include="..\..\src\video\SDL_fillrect.c" />
     <ClCompile Include="..\..\src\video\SDL_pixels.c" />
     <ClCompile Include="..\..\src\video\SDL_rect.c" />
@@ -419,6 +426,12 @@
       <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</CompileAsWinRT>
       <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</CompileAsWinRT>
     </ClCompile>
+    <ClCompile Include="..\..\src\video\winrt\SDL_winrtopengles.cpp">
+      <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</CompileAsWinRT>
+      <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</CompileAsWinRT>
+      <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Debug|ARM'">true</CompileAsWinRT>
+      <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Release|ARM'">true</CompileAsWinRT>
+    </ClCompile>
     <ClCompile Include="..\..\src\video\winrt\SDL_winrtpointerinput.cpp">
       <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Debug|ARM'">true</CompileAsWinRT>
       <CompileAsWinRT Condition="'$(Configuration)|$(Platform)'=='Release|ARM'">true</CompileAsWinRT>

VisualC-WinRT/WinPhone80_VS2012/SDL-WinPhone80.vcxproj.filters

@@ -360,6 +360,18 @@
     <ClInclude Include="..\..\src\joystick\windows\SDL_xinputjoystick_c.h">
       <Filter>Source Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\src\render\opengles2\SDL_gles2funcs.h">
+      <Filter>Source Files</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\src\render\opengles2\SDL_shaders_gles2.h">
+      <Filter>Source Files</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\src\video\winrt\SDL_winrtopengles.h">
+      <Filter>Source Files</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\src\video\SDL_egl_c.h">
+      <Filter>Source Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\src\atomic\SDL_atomic.c">
@@ -650,5 +662,17 @@
     <ClCompile Include="..\..\src\joystick\windows\SDL_xinputjoystick.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\render\opengles2\SDL_render_gles2.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\src\render\opengles2\SDL_shaders_gles2.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\src\video\winrt\SDL_winrtopengles.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\src\video\SDL_egl.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
 </Project>

include/SDL_config_winrt.h

@@ -173,10 +173,8 @@ typedef unsigned int uintptr_t;
 #define SDL_VIDEO_DRIVER_DUMMY  1
 
 /* Enable OpenGL ES 2.0 (via a modified ANGLE library) */
-#if WINAPI_FAMILY != WINAPI_FAMILY_PHONE_APP    /* TODO, WinRT: try adding OpenGL ES 2 support for Windows Phone 8 */
 #define SDL_VIDEO_OPENGL_ES2 1
 #define SDL_VIDEO_OPENGL_EGL 1
-#endif
 
 /* Enable appropriate renderer(s) */
 #define SDL_VIDEO_RENDER_D3D11  1