daily update on 20240213 by nitload youmu. 逐步弃用GLFW，正在使用wgl重写glfw底层，相关实现转移到C#实现，SSC彻底变成线性代数计算器。

源代码/StgSharp/Graphics/GL/glApiManager.cs

@@ -45,6 +45,14 @@ namespace StgSharp.Graphics
             IntPtr proc = loader("glGetString");
             context->glGetString = (delegate*<uint, IntPtr>)proc;
 
+            if ((IntPtr)context->glGetString == IntPtr.Zero)
+            {
+#if DEBUG
+                Console.WriteLine("Cannot load GL.");
+                throw new Exception("Cannot load gl");
+#endif
+            }
+
             string coreVersion;
             if (context->glGetString(glVersion) == IntPtr.Zero)
             {