mac-v0.1.13

Fix: the 60 FPS cap no longer costs frame rate in heavy scenes. With a frame rate cap, scenes that could not reach 60 (fire, cutscenes) ran up to 8% below what they reach without the cap: the GPU keep-alive added in 0.1.11 started between frames and took GPU time from the game. It now stays off whenever a frame rate cap is set.

On an M3 Max at a 60 cap: a burning village street 51.5 -> 56 FPS (the same as uncapped). The first Seattle street holds 60. A 30 cap holds 30 as before. Without a cap nothing changes.

Tip for recording videos: OBS left open costs about 13% FPS even when it is not recording, because its screen capture and preview keep running. Close it when you are just playing.

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Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

mac-v0.1.12

Long sessions on a MacBook Pro: use High Power. In the default Automatic Energy Mode macOS lowers the CPU clocks after about 3-4 minutes of play and the frame rate settles 15-20% lower (M3 Max, 9 minutes standing: bridge 101 -> 83 FPS, truck crash 75 -> 61). With System Settings -> Battery -> Energy Mode -> High Power (on a power adapter, on Macs that offer it) both held for the whole 9 minutes: bridge 102, truck crash 75. The fans run louder.

New

• Launcher: an Energy Mode hint. On a power adapter in Automatic mode it suggests High Power for long sessions, with a button that opens Battery settings; with Low Power Mode on it says the game runs much slower. It never changes the setting.

Faster / lighter

• Less CPU work per draw: the particles' compute dispatches no longer enter the graphics queue's barrier tracking (bridge ~95 -> 98 FPS), and the GPU command thread no longer wakes thousands of times a frame while it waits (30-50% less CPU on that thread). Same picture.

Checked: the burning building at a 30 FPS cap (issue #11), the smoke tutorial and the chase; 9-minute runs; unit tests.

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Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

mac-v0.1.11

Fixes

• The frame rate no longer sinks during a session. This was a regression in 0.1.10: a helper thread asked MoltenVK to wait for the GPU about 4,000 times a second, and every wait left a listener behind inside Metal. After 10 minutes in Seattle the frame rate had gone from about 74 to 62 FPS. If you saw 0.1.10 get slower the longer you played, this is it.
• The frame rate no longer halves after about 40 seconds in some scenes. Where the game is limited by the CPU side, the GPU was about 94% busy, and macOS clocked it down to its slowest state and left it there (Seattle: 72 -> 33 FPS while standing still). The GPU process now fills the short gaps with a tiny compute job, only while it is needed. TLG_GPU_KEEPALIVE=0 turns it off.

Faster (M3 Max, 1080p, default settings, 3 runs of 60 s each)

Scene	0.1.10	0.1.11
Truck crash (the launcher's Benchmark)	70	76
Bridge after the car crash	87	99
First Seattle street	63, then ~33 after 40 s	72, steady

• MoltenVK encodes Metal commands as they are recorded, not after each submission.
• The particle chain no longer restarts a GPU encoder at each of its ~28 fences a frame.
• A 2 MiB image is copied off the GPU once a frame, not ~11 times.

New

• Launcher, Advanced > Quality: Shadow detail (Full / Lower / Lowest; default Full). Fewer sun-shadow cascades: about half the draws at Lowest in open sunlit scenes (truck crash 73 -> 80 FPS). No effect at night or in the city.

The picture is unchanged at default settings.

---

Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

mac-v0.1.10

Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

mac-v0.1.9

Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

mac-v0.1.8

Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

What's new in 0.1.8

• Less CPU work per draw again: the truck crash (Benchmark) 47 -> 49 FPS and the bridge 66 -> 68 on an M3 Max. The picture is the same.
• Launcher, Advanced > Quality: a performance preset. "Slower Mac" sets lower detail, a 30 FPS cap and 67% render scale; "Slowest" sets lowest detail, 30 FPS, 50% and no smoke and sparks. A starting point for M1/M2-class Macs: please run the Benchmark and share the result.
• Known: the frame rate can halve while the game is not the front app (macOS clocks the GPU down for a window behind another app). Play in full screen.

mac-v0.1.7

Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

What's new in 0.1.7

• Less CPU work per draw in the GPU process: the truck crash (Benchmark) 43 -> 47 FPS on an M3 Max. The picture is the same.
• From 0.1.6: the game's particle work on its own GPU queue (bridge 60 -> 65 FPS). TLG_ACB_QUEUE=0 turns it off.

mac-v0.1.6

Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

What's new in 0.1.6

• The game's particle work (smoke, sparks, rain) runs on its own GPU queue, so its results no longer wait behind the frame's graphics. On an M3 Max: bridge 60 -> 65 FPS standing, 49 -> 53 turning the camera; the truck crash (Benchmark) stays at 45. Smoke looks the same as in 0.1.5.
• If something looks wrong, TLG_ACB_QUEUE=0 turns it off (as 0.1.5).

mac-v0.1.5

Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.

mac-v0.1.4

Test version. You need your own decrypted copy of the game with update 1.07.

The app is not notarised, so macOS blocks it after download. Move ISS.app to Applications, then run:

xattr -dr com.apple.quarantine /Applications/ISS.app

See the README for setup and known issues.