304 CHAPTER 9: Performance ’n’ Stuff^
#Lines Rendered: The number of line primitives rendered.
#Platform Calls: The total instantaneous number of iOS calls per
frame.
#Points Rendered: The number of point primitives rendered. For my
test case, it shows 880,000 on my iPad 1, affectionately called
Newton. (Think about it.) You can also equate those to vertices
processed.
#Redundant State Changes: As mentioned previously, the total count
per frame of unnecessary state changes. I am currently showing only- Your goal would be to get this value down to 0.
#Render Passes: The handle to track multipass rendering.
#Texture Uploads: The number of textures uploaded to the hardware.
#Triangles Rendered: The total number of triangle primitives rendered.
My test app is currently showing a total of 879,978 triangles per frame
racing along 3 FPS on my iPad 1. Of course, things like triangle counts
are only relative because they can vary wildly depending on size and
direction.
Target Selector
When launched from Xcode, your running app will appear here. It will also let you select
any device or any other apps under development.Track Display
The displayed traces are the ones selected from the inspector’s panel in the section
‘‘Frame Statistics to Observe.’’ You can stack the displays or overlay them one on top of
the other. And clicking and dragging the little transparent wedge thing along the time
scale will display the actual values of any of the traces at a specific time, as shown in
Figure 9-11.