From 4805796fea00d5d5b01d0ef624696c3f8a63e6ad Mon Sep 17 00:00:00 2001
From: parker <parker.g.britt@gmail.com>
Date: Thu, 26 Jun 2025 19:50:15 +0100
Subject: [PATCH] refactor: create GLMesh class

---
 CMakeLists.txt                        |  1 +
 src/gui/viewport/GLMesh.cpp           | 57 +++++++++++++++++++++++++++
 src/gui/viewport/GLMesh.h             | 17 ++++++++
 src/gui/viewport/ViewportGLWidget.cpp | 31 +++------------
 src/gui/viewport/ViewportGLWidget.h   |  3 +-
 5 files changed, 82 insertions(+), 27 deletions(-)
 create mode 100644 src/gui/viewport/GLMesh.cpp
 create mode 100644 src/gui/viewport/GLMesh.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b7dff8b..ef9c472 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,6 +26,7 @@ qt_add_executable(${AppExec}
     src/gui/viewport/Viewport.cpp
     src/gui/viewport/ViewportGLWidget.cpp
     src/gui/viewport/GLCamera.cpp
+    src/gui/viewport/GLMesh.cpp
     src/gui/network/NetworkGraphicsView.cpp
     src/gui/network/NetworkGraphicsScene.cpp
     src/gui/network/Network.cpp
diff --git a/src/gui/viewport/GLMesh.cpp b/src/gui/viewport/GLMesh.cpp
new file mode 100644
index 0000000..7634494
--- /dev/null
+++ b/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);
+}
diff --git a/src/gui/viewport/GLMesh.h b/src/gui/viewport/GLMesh.h
new file mode 100644
index 0000000..40d893c
--- /dev/null
+++ b/src/gui/viewport/GLMesh.h
@@ -0,0 +1,17 @@
+#pragma once
+#include <QOpenGLFunctions_3_2_Core>
+
+class GLMesh
+: protected QOpenGLFunctions_3_2_Core
+{
+public:
+    GLMesh();
+    GLuint vao;
+    GLuint vbo;
+
+    void init();
+    void initBuffers();
+    void bind();
+    void unbind();
+    void draw();
+};
diff --git a/src/gui/viewport/ViewportGLWidget.cpp b/src/gui/viewport/ViewportGLWidget.cpp
index 0b7cca6..9d69694 100644
--- a/src/gui/viewport/ViewportGLWidget.cpp
+++ b/src/gui/viewport/ViewportGLWidget.cpp
@@ -1,14 +1,18 @@
 #include "gui/viewport/ViewportGLWidget.h"
+#include "gui/viewport/GLMesh.h"
 #include <glm/mat4x4.hpp>
 #include <glm/ext/matrix_clip_space.hpp>
 #include <glm/gtc/matrix_transform.hpp>
 #include <glm/gtc/type_ptr.hpp>
+#include <memory>
 #include <qtimer.h>
 
 void ViewportGLWidget::initializeGL()
 {
     initializeOpenGLFunctions();
 
+    triangleMesh_ = std::make_unique<GLMesh>();
+
     QSurfaceFormat fmt = context()->format();
     std::cout << "format: " << (fmt.renderableType() == QSurfaceFormat::OpenGLES ? "GLES" : "Desktop") << "\n";
     std::cout << "format: " << (fmt.renderableType() == QSurfaceFormat::OpenGL ? "true" : "false") << "\n";
@@ -23,25 +27,6 @@ void ViewportGLWidget::initializeGL()
     curCamera = GLCamera();
 
 
-
-    glGenVertexArrays(1, &vao);
-    glBindVertexArray(vao);
-
-    float vertices[] = {
-        -0.5f, -0.5f, 0.0f,
-         0.5f, -0.5f, 0.0f,
-         0.0f,  0.5f, 0.0f
-    };
-
-    GLuint vbo;
-    // 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);
-
-
     // vertex shader
     const std::string vertexShaderSource = "#version 330 core\n"
     "uniform mat4 uView;\n"
@@ -101,11 +86,6 @@ void ViewportGLWidget::initializeGL()
     glDeleteShader(vertexShader);
     glDeleteShader(fragmentShader);
 
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3*sizeof(GLfloat), (void*)0);
-    glEnableVertexAttribArray(0);
-
-    // unbind vertex array
-    glBindVertexArray(0);
 
 
     glClearColor(0.16f, 0.16f, 0.16f, 1.0f);
@@ -140,7 +120,6 @@ void ViewportGLWidget::paintGL()
     curCamera.setUniform(viewMLoc);
 
 
+    triangleMesh_->draw();
 
-    glBindVertexArray(vao);
-    glDrawArrays(GL_TRIANGLES, 0, 3);
 }
diff --git a/src/gui/viewport/ViewportGLWidget.h b/src/gui/viewport/ViewportGLWidget.h
index 11325b1..d1f1b1e 100644
--- a/src/gui/viewport/ViewportGLWidget.h
+++ b/src/gui/viewport/ViewportGLWidget.h
@@ -4,15 +4,16 @@
 #include <iostream>
 #include <QOpenGLFunctions_3_2_Core>
 #include "gui/viewport/GLCamera.h"
+#include "gui/viewport/GLMesh.h"
 
 class ViewportGLWidget : public QOpenGLWidget, protected QOpenGLFunctions_3_2_Core
 {
 public:
     ViewportGLWidget(QWidget *parent) : QOpenGLWidget(parent) { }
     QSize sizeHint() const override { return QSize(-1, -1); }
-    GLuint vao;
     GLuint shaderProgram;
     GLCamera curCamera;
+    std::unique_ptr<GLMesh> triangleMesh_ ;
 
 protected:
     void initializeGL() override;