Now, when we know that the frame rate is important, let's have a look once again at those debug labels that are displayed in the left bottom corner. Refer to the following screenshot:
The following explains each numbered line shown in the preceding screenshot:
The number of OpenGL draw calls per frame: Each call to the OpenGL draw function has a performance cost. We have four objects in our scene: background, bird, hunter's torso, and his legs. This gives us four OpenGL draw calls. If you add one more bird to the scene, this number will increase to five and so on. Soon, I will show you how to draw several objects in one call and increase performance.
Time required to render one frame.
The average framerate (FPS) the game is currently running.