3f73a18db1
Co-authored-by: f1zz1ec0ke <220638765+f1zz1ec0ke@users.noreply.github.com> Co-authored-by: danturn <7792186+danturn@users.noreply.github.com> Co-authored-by: JunielKatarn <4507319+JunielKatarn@users.noreply.github.com> Co-authored-by: italoarruda <3868006+italoarruda@users.noreply.github.com> Co-authored-by: dolent <16023813+dolent@users.noreply.github.com>
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title, description, date, modified_time
| title | description | date | modified_time |
|---|---|---|---|
| Framerate and pacing | How the GoldenEye 007 PC port holds a steady 60 fps, draws frames above 60 on fast displays, and keeps per-frame game timing correct on a fast CPU. | 2026-10-05 | 2026-10-10 |
Framerate and pacing
The port targets a steady 60 fps with VSync and a frame cap, including on low-end GPUs. Since v0.6.0 the cap can also go above 60 on a faster display (see Above 60 fps).
The N64's game code assumed a 60 Hz vertical-interrupt tick — it ran a few ticks per displayed frame. On a PC the CPU is far faster, so left alone the game logic would race ahead. The port handles this in two places:
- Frame pacing happens in
port/src/video.con the render thread (the software RSP thread), which paces the frame and does the swap and FPS accounting. - Per-frame counters in the game are gated with
portN64FrameStep()so they advance at the display rate, not the CPU rate. Getting this wrong is a recurring class of subtle timing bug (a counter that ticks too fast, a stall that isn't real) — the porting notes track these (for example D13, D22 and D486).
On very weak integrated GPUs (Atom/Celeron class) the first launch writes
lighter values for draw distance, LOD distance and anti-aliasing into
ge007.ini so the game still holds 60 fps.
Above 60 fps
Video.FpsCap (F10, Frame rate cap) accepts Auto, 30, 60, 90, 120 and 144.
Auto is the default on fresh installs (an existing ge007.ini keeps its
value) and matches the display's refresh rate, up to 144; on a 60 Hz display it
is plain 60.
- The game still simulates at its original 60 Hz (NTSC) tick. The extra frames are drawn between two game ticks by blending the previous and current frame's matrices (camera and objects), so no game state changes.
- Cost: one game tick of extra latency.
- Inert on 60 Hz displays. The present rate is the lower of the cap and the display's refresh rate. The Original N64 display mode caps at 60.
- Fallbacks: a fast camera turn or a large change in the visible room set draws a full (non-blended) frame instead.
- The design comes from f1zz1ec0ke's PR #137; the port reworked it onto the render worker thread and from a fixed 2x to any present rate, so a 90 Hz Steam Deck OLED works (D578, D583, D584).
Checked by the maintainer: 120 Hz with VSync on a G-Sync display on PC, and 90 fps on the Steam Deck. Known issue: on the Deck at 90, centre firefights in Bunker 1/2 can drop several fps, and Jungle can feel slightly less smooth.
More: porting notes — the timing-related findings (D13, D22, D486).