diff --git a/src/renderer/mesh.cpp b/src/renderer/mesh.cpp
index 544c2e7..ee02817 100644
--- a/src/renderer/mesh.cpp
+++ b/src/renderer/mesh.cpp
@@ -1,3 +1,5 @@
+#include <cstddef>
+
 #include "renderer/mesh.h"
 
 Mesh::Mesh() {
@@ -13,13 +15,21 @@ Mesh::Mesh() {
 
     // VBO (vertex buffer)
     glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
-    glBufferData(GL_ARRAY_BUFFER, 0, nullptr, GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, 0, nullptr, GL_DYNAMIC_DRAW);
 
     // EBO (index buffer)
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ebo);
-    glBufferData(GL_ELEMENT_ARRAY_BUFFER, 0, nullptr, GL_STATIC_DRAW);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, 0, nullptr, GL_DYNAMIC_DRAW);
 
-    Vertex::DefineAttrib();
+    // attributes
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<const void*>(offsetof(Vertex, m_position)));
+    glEnableVertexAttribArray(0);
+
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<const void*>(offsetof(Vertex, m_normal)));
+    glEnableVertexAttribArray(1);
+    
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<const void*>(offsetof(Vertex, m_texCoord)));
+    glEnableVertexAttribArray(2);
 
     glBindBuffer(GL_ARRAY_BUFFER, 0);
     glBindVertexArray(0);
@@ -29,18 +39,22 @@ void Mesh::Upload() const {
     glBindVertexArray(m_vao);
 
     glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
-    glBufferData(GL_ARRAY_BUFFER, m_vertexBuffer.size() * sizeof(Vertex), m_vertexBuffer.data(), GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, m_vertexBuffer.size() * sizeof(Vertex), m_vertexBuffer.data(), GL_DYNAMIC_DRAW);
 
     // Upload indices
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ebo);
-    glBufferData(GL_ELEMENT_ARRAY_BUFFER, m_indexBuffer.size() * sizeof(unsigned int), m_indexBuffer.data(), GL_STATIC_DRAW);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, m_indexBuffer.size() * sizeof(unsigned int), m_indexBuffer.data(), GL_DYNAMIC_DRAW);
 
     glBindVertexArray(0);
 }
 
-void Mesh::Render()
+void Mesh::Render(unsigned int count)
 {
     Bind();
-    glDrawElements(GL_TRIANGLES, static_cast<GLsizei>(m_indexBuffer.size()), GL_UNSIGNED_INT, 0);
+    if (count > 1) {
+        glDrawElementsInstanced(GL_TRIANGLES, static_cast<GLsizei>(m_indexBuffer.size()), GL_UNSIGNED_INT, 0, count);
+    } else {
+        glDrawElements(GL_TRIANGLES, static_cast<GLsizei>(m_indexBuffer.size()), GL_UNSIGNED_INT, 0);
+    }
     Unbind();
 }
\ No newline at end of file