--- a/opengl.h	Wed Nov 29 01:27:05 2023 +0100
+++ b/opengl.h	Fri Dec 01 20:25:49 2023 +0100
@@ -17,6 +17,7 @@
 
 #pragma once
 
+#include <iostream>
 #include <string>
 #include <stdexcept>
 
@@ -27,6 +28,8 @@
 #include <glm/glm.hpp>
 #include <glm/ext.hpp>
 
+#include "Shader.h"
+
 inline
 void quads(GLfloat tx, GLfloat ty, GLfloat x, GLfloat y, GLfloat z) {
 	glTexCoord2f(tx, ty);
@@ -34,7 +37,7 @@
 }
 
 inline
-void checkError(std::ostream* out) {
+void checkError(std::ostream* out = nullptr) {
 	GLenum code = glGetError();
 	if (code == GL_NO_ERROR) {
 		if (out) *out << "GL check: OK" << std::endl;
@@ -46,9 +49,9 @@
 }
 
 inline
-GLenum toShaderType(const std::string& fileName) {
-	if (fileName.ends_with(".vert")) return GL_VERTEX_SHADER;
-	else if (fileName.ends_with(".frag")) return GL_FRAGMENT_SHADER;
+Shader::Type toShaderType(const std::string& fileName) {
+	if (fileName.ends_with(".vert")) return Shader::Type::VERTEX;
+	else if (fileName.ends_with(".frag")) return Shader::Type::FRAGMENT;
 	else throw std::invalid_argument("Expecting *.vert or *.frag file");
 }