Output Channels

Funscripts come in flavours. Each flavour is a separate file with its own name suffix:

Channel	Suffix	Used by
Main	.funscript	Standard linear devices (Handy, Kiiroo, etc.)
Multi-axis	.pitch.funscript, .roll.funscript, .surge.funscript, .sway.funscript, .twist.funscript	SR6 / OSR2 and similar 6DOF rigs
3-phase estim	.alpha.funscript, .beta.funscript	restim 3-phase rigs
Prostate	.alpha-prostate.funscript, .beta-prostate.funscript	restim prostate variants
4-phase estim (Phase 2)	.e1.funscript, .e2.funscript, .e3.funscript	restim 4-phase rigs — concat not yet wired

The sidebar Output channels section lets you pick which channels get written for the combined output.

How detection works

When you add a clip, ForgeAssembler looks for matching funscript files in:

1. The same folder as the clip (your_clip.mp4 → your_clip.funscript, your_clip.multi_axis.funscript, …)
2. Named sub-folders: estim/, multi_axis/, prostate/, audio_estim/ — matching the FunscriptForge output layout

Root-level matches win over sub-folder dupes if the same name appears in both places.

Detected channels show up on each segment card as Funscripts: main, multi_axis, e1, e2, e3, prostate, ….

How concatenation works

For each enabled channel, ForgeAssembler walks every segment in playback order and stitches the funscript timelines back-to-back. Gaps (fade-to-black bridges) produce silent stretches in the funscript.

If a specific clip is missing a channel you've enabled, the engine leaves that gap silent rather than failing — so a project with one clip that doesn't have multi-axis still produces a valid <project>.multi_axis.funscript with gaps for the missing stretch.

Default channels

By default ForgeAssembler writes main, multi_axis, three_phase_estim, and prostate. Turn channels off in the sidebar if you want fewer files.

Phase-2 channels (not yet implemented)

The sidebar also shows four_phase_estim and pulse_frequency. These are off by default because the concat logic isn't written yet. Safe to ignore until a future release lands them.

Haptic-estim audio (per-channel WAVs)

Some haptic toolchains generate audio files alongside the funscripts — restim, for example, can render .stereostim.wav, .legacy.wav, and .prostate.stereostim.wav from a funscript and a device profile. ForgeAssembler concatenates these in lockstep with the video.

When Audio (haptic estim) is on in the Produce panel, the engine:

1. Walks each segment looking for .stereostim.wav / .legacy.wav / .prostate.stereostim.wav siblings (immediate folder, plus the same channel sub-folders that funscript detection scans).
2. For each channel that any segment carries, concatenates the per-segment audio into one combined output WAV named <basename>.stereostim.wav, <basename>.legacy.wav, etc.
3. Segments missing a channel get silence-filled at 48 kHz stereo so the combined WAV stays lockstep with the video. This means a project with one segment that has a stereostim.wav and three that don't still produces a valid 48 kHz stereo <basename>.stereostim.wav with silence in the gaps.
4. Channels with no audio in any segment are skipped (no useless 100%-silent files).

By design, the engine emits every estim channel any segment carries — stereostim, legacy, and prostate — regardless of whether your current device needs them. The downstream player (ForgePlayer, or whatever your setup uses) selects the right channel at playback time based on the user's hardware profile. Forge time produces all artifacts; playback time consumes only what's relevant. This keeps forged outputs portable across devices without re-rendering.

Per-segment trim windows (Split clip at time…) propagate to the audio inputs the same way they do to video — -ss <trim_start> and -t <effective_duration>.

Produce video / funscripts / audio without the others

In the Produce panel of the sidebar:

• Video (MP4) — on by default
• Funscripts — on by default
• Audio (haptic estim) — on by default

Each toggle is independent. You can turn off Video to render only the funscript bundle (faster — no ffmpeg encoding). You can turn off Funscripts and Audio to render only the long video. At least one of the three must be on.

Heatmap

When Produce video is on, ForgeAssembler also writes a .heatmap.png alongside the output. It's a visual density map of the main funscript track across the whole combined output. Handy for a quick read of pacing — dense stretches, quiet stretches, spikes.

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Next: Debug mode — what to turn on when something goes wrong, and how to capture a clean bug report.