add missing file

src/platform/gl.cpp

@@ -0,0 +1,23 @@
+#include <llmr/platform/gl.hpp>
+
+#include <iostream>
+
+void _CHECK_GL_ERROR(const char *cmd, const char *file, int line) {
+    std::cout <<  cmd << ";" << std::endl;
+
+    GLenum err;
+
+    while ((err = glGetError()) != GL_NO_ERROR) {
+        std::string error;
+        switch (err) {
+            case GL_INVALID_OPERATION: error = "INVALID_OPERATION"; break;
+            case GL_INVALID_ENUM: error = "INVALID_ENUM"; break;
+            case GL_INVALID_VALUE: error = "INVALID_VALUE"; break;
+            case GL_OUT_OF_MEMORY: error = "OUT_OF_MEMORY"; break;
+            case GL_INVALID_FRAMEBUFFER_OPERATION:  error = "INVALID_FRAMEBUFFER_OPERATION";  break;
+        }
+
+        std::cerr << "GL_" << error.c_str() << " - " << file << ":" << line << std::endl;
+        exit(1);
+    }
+}