diff --git a/CMakeLists.txt b/CMakeLists.txt
index be89900..0600e95 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -40,6 +40,9 @@ qt_add_executable(${AppExec}
     src/gui/network/FloatingEdgeGraphic.cpp
     src/gui/network/DisplayFlagButton.cpp
     src/gui/network/NodeIconGraphic.cpp
+
+    src/Engine/Operator/Attribute.cpp
+    src/Engine/Operator/Geometry.cpp
 )
 
 target_link_libraries(${AppExec} PRIVATE Qt6::Core Qt6::Widgets Qt6::SvgWidgets Qt6::OpenGLWidgets glm::glm)
diff --git a/src/gui/viewport/GLMesh.cpp b/src/gui/viewport/GLMesh.cpp
index 7634494..50b98d4 100644
--- a/src/gui/viewport/GLMesh.cpp
+++ b/src/gui/viewport/GLMesh.cpp
@@ -1,4 +1,5 @@
 #include "gui/viewport/GLMesh.h"
+#include <GL/gl.h>
 #include <iostream>
 
 GLMesh::GLMesh()
@@ -21,23 +22,34 @@ void GLMesh::init()
 void GLMesh::initBuffers()
 {
 
-    float vertices[] = {
+    vertexPosData = {
         -0.5f, -0.5f, 0.0f,
          0.5f, -0.5f, 0.0f,
-         0.0f,  0.5f, 0.0f
+         0.0f,  0.5f, 0.0f,
+         0.5f, 0.5f, 0.0f
+    };
+
+    indexData =
+    {
+        0, 1, 2, 1, 2, 3
     };
 
     // create buffer of vertices
-    glGenBuffers(1, &vbo);
+    glGenBuffers(1, &vertexBuffer);
     // set purpose
-    glBindBuffer(GL_ARRAY_BUFFER, vbo);
+    glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
     // store data in the buffer
-    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, vertexPosData.size()*sizeof(GLfloat), vertexPosData.data(), GL_STATIC_DRAW);
 
-    // gives the shader a way to read 
+    // gives the shader a way to read buffer data 
     glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3*sizeof(GLfloat), (void*)0);
     // disable vertex attrib array
     glEnableVertexAttribArray(0);
+
+    glGenBuffers(1, &indexBuffer);
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexData.size()*sizeof(GLint), indexData.data(), GL_STATIC_DRAW);
+
 }
 
 void GLMesh::bind()
@@ -53,5 +65,9 @@ void GLMesh::unbind()
 void GLMesh::draw()
 {
     bind();
-    glDrawArrays(GL_TRIANGLES, 0, 3);
+
+    // wireframe
+    glPolygonMode( GL_FRONT_AND_BACK, GL_LINE );
+
+    glDrawElements(GL_TRIANGLES, indexData.size(), GL_UNSIGNED_INT, 0);
 }
diff --git a/src/gui/viewport/GLMesh.h b/src/gui/viewport/GLMesh.h
index 40d893c..3eeae88 100644
--- a/src/gui/viewport/GLMesh.h
+++ b/src/gui/viewport/GLMesh.h
@@ -1,4 +1,5 @@
 #pragma once
+#include <GL/gl.h>
 #include <QOpenGLFunctions_3_2_Core>
 
 class GLMesh
@@ -7,7 +8,11 @@ class GLMesh
 public:
     GLMesh();
     GLuint vao;
-    GLuint vbo;
+    GLuint vertexBuffer;
+    GLuint indexBuffer;
+
+    std::vector<GLfloat> vertexPosData;
+    std::vector<GLint> indexData;
 
     void init();
     void initBuffers();
diff --git a/src/gui/viewport/ViewportGLWidget.cpp b/src/gui/viewport/ViewportGLWidget.cpp
index b9c61d5..041d56e 100644
--- a/src/gui/viewport/ViewportGLWidget.cpp
+++ b/src/gui/viewport/ViewportGLWidget.cpp
@@ -1,14 +1,15 @@
-#include "gui/viewport/ViewportGLWidget.h"
-#include "gui/viewport/GLMesh.h"
+#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>
+#include "Engine/Operator/Geometry.h"
 
 void ViewportGLWidget::initializeGL()
 {
+    using namespace enzo;
     initializeOpenGLFunctions();
 
     glEnable(GL_DEPTH_TEST);
@@ -16,13 +17,13 @@ void ViewportGLWidget::initializeGL()
     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
     glEnable(GL_MULTISAMPLE);
 
-    triangleMesh_ = std::make_unique<GLMesh>();
+    auto geo = std::make_unique<enzo::geo::Geometry>();
+    triangleMesh_ = meshFromGeo(geo);
     gridMesh_ = std::make_unique<GLGrid>();
 
     QSurfaceFormat fmt = context()->format();
     std::cout << "format: " << (fmt.renderableType() == QSurfaceFormat::OpenGLES ? "GLES" : "Desktop") << "\n";
     std::cout << "format: " << (fmt.renderableType() == QSurfaceFormat::OpenGL ? "true" : "false") << "\n";
-    std::cout << "hello\n";
 
     // init loop
     QTimer* loopTimer = new QTimer(this);
@@ -136,3 +137,10 @@ void ViewportGLWidget::paintGL()
 
 
 }
+
+std::unique_ptr<GLMesh> ViewportGLWidget::meshFromGeo(std::unique_ptr<enzo::geo::Geometry>& geometry)
+{
+    auto mesh = std::make_unique<GLMesh>();
+    return mesh; 
+}
+
diff --git a/src/gui/viewport/ViewportGLWidget.h b/src/gui/viewport/ViewportGLWidget.h
index 9c46399..620edb9 100644
--- a/src/gui/viewport/ViewportGLWidget.h
+++ b/src/gui/viewport/ViewportGLWidget.h
@@ -6,6 +6,7 @@
 #include "gui/viewport/GLCamera.h"
 #include "gui/viewport/GLMesh.h"
 #include "gui/viewport/GLGrid.h"
+#include "Engine/Operator/Geometry.h"
 
 class ViewportGLWidget : public QOpenGLWidget, protected QOpenGLFunctions_3_2_Core
 {
@@ -17,6 +18,8 @@ public:
     std::unique_ptr<GLMesh> triangleMesh_ ;
     std::unique_ptr<GLGrid> gridMesh_ ;
 
+    std::unique_ptr<GLMesh> meshFromGeo(std::unique_ptr<enzo::geo::Geometry>& geometry);
+
 protected:
     void initializeGL() override;
     void resizeGL(int w, int h) override;