[Feat] (MG_Util/Converters): add symbolic constants for default FBO into ConvertFramebufferAttachmentTypeToGLEnum

MobileGL/MG_Util/Converters/MGToGL/FramebufferEnumConverter.cpp

@@ -29,12 +29,20 @@ namespace MobileGL {
             }
 
             switch (type) {
-            case FramebufferAttachmentType::Depth:
+                case FramebufferAttachmentType::Depth:
-                return GL_DEPTH_ATTACHMENT;
+                    return GL_DEPTH_ATTACHMENT;
-            case FramebufferAttachmentType::Stencil:
+                case FramebufferAttachmentType::Stencil:
-                return GL_STENCIL_ATTACHMENT;
+                    return GL_STENCIL_ATTACHMENT;
-            default:
+                case FramebufferAttachmentType::FrontLeft:
-                return GL_NONE;
+                    return GL_FRONT_LEFT;
+                case FramebufferAttachmentType::FrontRight:
+                    return GL_FRONT_RIGHT;
+                case FramebufferAttachmentType::BackLeft:
+                    return GL_BACK_LEFT;
+                case FramebufferAttachmentType::BackRight:
+                    return GL_BACK_RIGHT;
+                default:
+                    return GL_NONE;
             }
         }