In this chapter, we will learn how to use OpenGL 3 with Qt 5. Common OpenGL functions such as glBegin, glVertex2f, glColor3f, glMatrixMode, and glLoadIdentity have all been removed from OpenGL 3. OpenGL 3 uses vertex buffer objects to send data to the GPU in batches instead of sending them one by one through functions such as glVertex2f(), which slows down the rendering while waiting for the CPU to submit the data one by one. Therefore, we will pack all of the data into vertex buffer objects and send it all in one huge package to the GPU and instruct the GPU to calculate the resulting pixels through shader programming. We will also be learning about how to create simple shader programs through a C-like programming language called OpenGL Shading Language (GLSL).