We are doing video display output from multiple video sources concurrently with Yocto 1.7, Linux 3.10.17, gstreamer 1.2.3, and gstreamer_imx directly to the Linux framebuffer (without X11) on a iMX6 dual processor (GPU is Vivante).
We've noticed video tearing, and want to eliminate that tearing. The video tearing is illustrated here: Screen tearing - Wikipedia, the free encyclopedia.
We suspect the video tearing is due to performing OpenGL operations (swapping a buffer to the screen) when the HDMI vsync occurs.
Are there any alternate theories as to why the tearing occurs?
How can I write code that detects when this vsync occurs (polling is fine if that's the only way)?