Releases 0.10 and 0.11: an engine and a game shell

The work after 0.9 had three steps: split the engine out of the viewer, build a game shell, then build a sandbox on a bigger city. Release 0.10 was the split. Release 0.11 was the shell, a game application that boots, shows a title and menus, and plays.

Engine

• The simulation, fracture and step pipeline moved out of the viewer into engine modules in numbered steps, S1 to S10. After each step a check compared a state digest, a fingerprint of every body’s position, for frame benches, captures and two of our recorded sessions against a saved baseline. Every step left the digests identical except one.
• That one change is deliberate. Fracture now reads where a body is in the physics world, not where it was last drawn. Of 40 runs, 12 were unchanged. Scene 8’s demo now ends with 1,690 bodies against 2,068.
• A scene can run headless, with no window, renderer or sound, and ends in the same state as the app. All 13 frame-bench scenes match. When it covered ten scenes, a headless pass took about a minute where the rendered runs took about ten.
• The engine was named and given a splash screen of about three seconds.
• Replays, benchmarks and recordings no longer take the keyboard. They had activated their windows on launch, so a stray T pressed in another app switched quality tiers mid-run, and one run in five ended in a different state.
• Floors that a gutted story let go no longer land back on the columns it kept. In a replay of one of our sessions, members left within half a meter of where they were built, more than 10 m up, fell from 385 to 21.
• We wanted the finish on concrete and plaster to spall before the core breaks, as stucco does when a car hits it. The first version read as a decal laid on the wall, so the broken edge was reshaped to read as cut into the member. A blast spalls the finish on up to 40 members and costs at most 1 ms.

Game

• A game bundle opens on a photosensitivity warning, the engine splash and a title screen. The warning holds about six seconds and can be skipped after one and a half. Any key, click or gamepad button skips a screen.
• Behind the title, three cities come down in turn, 40 s each, while the camera circles them.
• Menus work from the keyboard, the mouse or a gamepad, and the menus and settings were tested with an Xbox controller. Settings are kept between launches and cover quality, shadows, bloom, sound, volume, slow motion, look speed and more. A new setting appears in the menu by itself.
• On the low tier in Low Power Mode, the title holds a p95 frame time under 16.7 ms.
• The sandbox takes a seed and plays the city it grows.
• Set charges go off in sequence, a quarter second apart, when the right button is pressed. We wanted sequential firing or a way to switch modes, and Shift fires them all at once as before.
• Two faults found in play are fixed. Starting a game with a gamepad now captures the mouse, and set charges, which had gone invisible, show again.

Tools

• digests.sh runs the baseline check, with a weapons range scene that fires every weapon on a script so the digests cover them.
• One of our recorded game sessions, 1,591 shots in one city, replays twice to the same state digest.
• The game bundle links none of the development code. A build check fails if any development symbol appears in its binary.