showcase-video

1# Showcase video
2 
3A mod isn't finished until you can show it in 30 seconds. The toolchain is `um win record` (capture),
4`um video contact` (look), `um video compile` (edit), all ffmpeg + Pillow.
5 
6## 1. Make the take repeatable
7- **Script the action.** Use a mod-side timeline or command sequence (spawn enemies, fire the weapon, cue
8  the boss), a scenario with triggers and camera moves, or a WinDrive command list. The first clean take
9  should be reproducible exactly, so you can reshoot after a fix.
10- **Restore the world before each take.** Explosions crater worlds; units die. Keep a pristine copy with
11  `um backup` and restore it every take.
12- **Clean frame.** Hide debug text, fix the camera zoom (the Terraria showcase used 1.5x so 1080p frames
13  read like a 720p cut), run at full speed when unfocused, and hide the cursor (capture uses
14  `capture_cursor=0`).
15 
16## 2. Record the window + the game's own audio
17```bash
18um win record --exe Game.exe --out C:\caps\take1 --seconds 40      # -> take1.mkv, take1.audio.raw, take1.json
19um video first-frame C:/caps/take1.mkv                              # where gameplay starts (skips loading screens)
20um video mux C:/caps/take1.mkv C:/caps/take1.audio.raw C:/caps/take1.json take1.mp4 [--offset 0.25]
21```
22- **Video:** ffmpeg gfxcapture of that window only (GPU frames, no desktop). It encodes with NVENC, AMF or
23  QSV when available. NVENC H.264 maxes out at **4096 px wide**, so the recorder scales above that; for
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