3.3 Hello_Triangle_pt3.md

• lets draw rectangle:)
• rectangle = 2 triangles = 6 vertices
• problem : total 4 unique vertices but 2 repeating
• solution : lets store only unique vertices and specify indices of vertices for each triangle

GLfloat indices[] = {
0, 1, 3, // first triangle
1, 2, 3 // second triangle
};

Element buffer Object serves this feature

• create VAO VBO EBO
• bind VAO
• bind VBO,EBO
• add data to VBO, EBO
• now use VAO to draw triangles!
• while drawing:
  • use glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
  • instead glDrawArrays(GL_TRIANGLES, 0, 6);
• imp: dont unbind EBO before VAO