Attempt implement menu (unresolved symbol error)

Util.cpp

@@ -0,0 +1,48 @@
+#include "Util.h"
+#include "stb_image.h"
+
+Util::Util()
+{
+}
+
+
+Util::~Util()
+{
+}
+
+GLuint Util::loadTexture(const std::string &filename)
+{
+	int width, height, bpp;
+
+	stbi_set_flip_vertically_on_load(true);
+	unsigned char* imgData = stbi_load(filename.c_str(), &width, &height, &bpp, 4);
+	GLuint num;
+	glGenTextures(1, &num);
+	glBindTexture(GL_TEXTURE_2D, num);
+
+	glTexImage2D(GL_TEXTURE_2D,
+		0,		//level
+		GL_RGBA,		//internal format
+		width,		//width
+		height,		//height
+		0,		//border
+		GL_RGBA,		//data format
+		GL_UNSIGNED_BYTE,	//data type
+		imgData);		//data
+	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
+
+	stbi_image_free(imgData);
+	return num;
+}
+
+void Util::glutBitmapString(std::string str, int x, int y)
+{
+	glRasterPos2f(x, y);
+	for (int i = 0; i < str.size(); i++)
+	{
+		glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, str[i]);
+	}
+}