refactor: create GLMesh class

src/gui/viewport/GLMesh.cpp

@@ -0,0 +1,57 @@
+#include "gui/viewport/GLMesh.h"
+#include <iostream>
+
+GLMesh::GLMesh()
+{
+    initializeOpenGLFunctions();
+    init();
+}
+
+void GLMesh::init()
+{
+    glGenVertexArrays(1, &vao);
+    glBindVertexArray(vao);
+
+    initBuffers();
+
+    // unbind vertex array
+    glBindVertexArray(0);
+}
+
+void GLMesh::initBuffers()
+{
+
+    float vertices[] = {
+        -0.5f, -0.5f, 0.0f,
+         0.5f, -0.5f, 0.0f,
+         0.0f,  0.5f, 0.0f
+    };
+
+    // create buffer of vertices
+    glGenBuffers(1, &vbo);
+    // set purpose
+    glBindBuffer(GL_ARRAY_BUFFER, vbo);
+    // store data in the buffer
+    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+
+    // gives the shader a way to read 
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3*sizeof(GLfloat), (void*)0);
+    // disable vertex attrib array
+    glEnableVertexAttribArray(0);
+}
+
+void GLMesh::bind()
+{
+    glBindVertexArray(vao);
+}
+
+void GLMesh::unbind()
+{
+    glBindVertexArray(0);
+}
+
+void GLMesh::draw()
+{
+    bind();
+    glDrawArrays(GL_TRIANGLES, 0, 3);
+}