promo-video

SKILL.md

Promo Video Recording

Record smooth, autonomous promo footage of a Phaser game for marketing / social media. The output is a 50 FPS MP4 in mobile portrait (9:16) — ready for TikTok, Reels, Moltbook, or X.

Technique

Playwright's recordVideo caps at 25 FPS with no config option. We work around it:

Slow the game to 0.5× by patching all 5 Phaser time subsystems

Record for 2× the desired duration at Playwright's native 25 FPS

FFmpeg speed-up 2× → effective 50 FPS output

Parameter
Default
Effect

SLOW_MO_FACTOR
0.5
Game runs at half speed → 50 FPS output

WALL_CLOCK_DURATION
DESIRED_GAME_DURATION / SLOW_MO_FACTOR
Record for 2× to get correct game-time

VIEWPORT
{ width: 1080, height: 1920 }
9:16 mobile portrait (always default unless user specifies otherwise)

DESIRED_GAME_DURATION
13000 (ms)
~13s of game-time → ~6.5s promo clip