D694 - A presented frame is the top rung

Status: decided Date: 2026-09-26

Reach::Presented sits above Flipped and is awarded when a run flipped a buffer holding pixels the guest wrote.

Why: a flip is a place reached, not a picture shown, and a ladder whose top rung everything reaches says nothing about the work left. A buffer differing from its prior contents is a positive measurement, and it is the framebuffer comparison the project already trusts. Flipped stays a real distance: an output opened, configured and flipped against real implementations.

Rejected:

• Replacing Flipped: loses the distance between flipping and faulting.
• Treating a flip as presentation: advertises output that does not exist.