Help & Documentation
Everything you need to set up and get the most out of Sprout.
Quick Start
Getting Sprout running with VTube Studio takes less than a minute.
- Download Sprout.exe and run it — no installer needed.
- A
icon appears in your system tray.
- In VTube Studio, enable Spout2 output (Settings → Spout2 → Start).
- Right-click the Sprout tray icon → Settings.
- Under General, set the Sender Name to match what VTube Studio reports (usually
VTubeStudioSpout). - Your avatar should now appear as a transparent overlay on your desktop.
Requirements
- OS: Windows 10 or 11 (64-bit)
- GPU: Any DirectX 11-compatible graphics card
- Spout2 source: VTube Studio, or any other Spout2-compatible application
- Runtime: None — Sprout is a self-contained single-file executable
First Run
On first launch, Sprout shows a brief hint overlay explaining the tray icon. Dismiss it by clicking anywhere on the overlay or waiting a few seconds.
All settings are stored in %AppData%\Sprout\ — Sprout creates this folder automatically.
General Settings
Sender Name
The name of the Spout2 source to receive from. Must match exactly what the sender application advertises.
- VTube Studio default:
VTubeStudioSpout - Check the sender app for the exact string — names are case-sensitive
Monitor
Which display the overlay appears on. Monitors are numbered starting from 0 (your primary display). Change this if the overlay appears on the wrong screen.
Click-Through
When enabled, mouse clicks and movements pass through the overlay to whatever is behind it. See Click-Through for more detail.
Fullscreen
Stretches the overlay to fill the entire monitor. When disabled, crop settings control the overlay size and position.
Over Taskbar
Controls whether the overlay sits above or below the Windows taskbar. Disable this if you want your taskbar accessible while the overlay is visible.
Display Settings
Base Opacity
How opaque the overlay is at rest, from 5% to 100%. At 100% the overlay is fully solid; lower values make it semi-transparent.
Crop
Trim pixels from each edge of the overlay frame. Useful for cutting away empty space in the Spout source or repositioning your avatar within the visible area.
- Top / Bottom / Left / Right — pixels to remove from each edge
- Changes take effect immediately with a live preview
Target FPS
How many frames per second Sprout renders. Options: 15, 20, 24, 30, 60.
- Lower FPS reduces GPU and CPU usage
- 60 FPS is recommended for smooth avatar motion
Hover Transparency
When enabled, the overlay fades to a lower opacity when your cursor moves over it, revealing what's underneath. The Hover Opacity slider sets how transparent it becomes.
Appearance Settings
Icon Color
Customize the color of the tray icon. Choose from preset colors or enter a hex code (e.g.,
#a6e3a1).
Advanced Settings
API
Enable or disable the HTTP REST API. When enabled, Sprout listens on port 5757 by default. The port is configurable if you have a conflict. See HTTP API for full documentation.
Hotkeys
Global hotkeys that work even when Sprout is not the active window.
- Quit Hotkey — exits Sprout (default:
Ctrl+Q) - Hide All Hotkey — instantly hides or shows all overlays
Multi-Source Mode
Enables the multi-source panel for displaying multiple Spout sources simultaneously. See Multi-Source for setup details.
Presets
Save and restore your full configuration as named presets. Useful for switching between different stream setups, games, or layouts instantly.
Saving a Preset
- Configure your overlay exactly how you want it.
- Open Settings → Presets tab.
- Type a name in the preset name field.
- Click Save.
Loading a Preset
- Open Settings → Presets tab.
- Select the preset from the dropdown.
- Click Load.
Presets are stored as JSON files in %AppData%\Sprout\presets\ and can be backed up, shared, or edited manually.
Click-Through Mode
Click-through makes the overlay completely transparent to mouse input — clicks, scrolls, and hover events all pass through to whatever window is behind Sprout.
Toggling Click-Through
- Right-click tray icon → Click-Through
- Or toggle in Settings → General
- Or via the HTTP API
Global Hotkeys
Global hotkeys are registered system-wide and fire even when Sprout isn't focused.
Default Bindings
Ctrl + Q— Quit Sprout- (configurable) — Hide/show all overlays
Change hotkeys in Settings → Advanced. Click the key field and press your desired combination.
Multi-Source Layering
Pro tier unlocks multi-source mode, letting you display multiple Spout2 sources simultaneously, each with independent settings.
Setup
- Enable Multi-Source Mode in Settings → Advanced.
- A source list panel appears in the Settings window.
- Click Add Source and configure each entry:
- Sender name, monitor, crop, opacity, FPS
- Click-through toggle per source
- Z-Order (higher = in front)
- Enable/disable individual sources using the checkbox without removing them.
Z-Order / Layering
Z-Order controls which source appears in front when overlays overlap. Higher numbers appear on top. Change values in the source settings panel.
Hide All
The Hide All toggle (tray menu or hotkey) hides every source at once without changing individual settings, and restores them just as quickly.
HTTP REST API
Enable the API in Settings → Advanced. Sprout listens at http://localhost:5757/ with full CORS support, so any HTTP client can reach it.
Endpoints
| Method | Path | Description |
|---|---|---|
| GET | /settings |
Return all current settings as JSON |
| POST | /settings |
Update one or more settings (partial updates supported) |
| GET | /sources |
List all multi-source entries |
| POST | /sources |
Add or update a source entry |
| DELETE | /sources/{id} |
Remove a source by ID |
| GET | /presets |
List all saved presets |
| POST | /presets/load |
Load a preset by name |
| DELETE | /presets/{name} |
Delete a saved preset |
Examples
Get current settings (PowerShell):
Toggle click-through (curl):
Change opacity from JavaScript:
Load a preset (curl):
Licensing
Sprout uses a one-time license key purchased through Gumroad. After purchase you'll receive a license key via email.
Activating a License
- Right-click the tray icon → License.
- Enter your license key in the field.
- Click Activate.
- Sprout verifies the key online and unlocks the appropriate tier.
Offline Use
After the first successful activation, Sprout caches your license locally at %AppData%\Sprout\license.json. You can use Sprout offline without re-verifying each launch.
Tiers
- Free — single source, basic display controls
- Plus — adds API, presets, hotkeys, hover transparency, FPS control, icon color
- Pro — everything in Plus, plus multi-source layering
Troubleshooting: No Overlay Showing
Check the sender name
The most common cause. Go to Settings → General and confirm the Sender Name matches exactly what your Spout2 app is broadcasting (case-sensitive).
Is the Spout source active?
The sender application must be running and actively transmitting. In VTube Studio, check that Spout2 output is enabled and the model is loaded.
Verify the overlay isn't hidden
Check the tray menu — if Hide All is checked, click it to show overlays again. Also check that the Hide toggle for individual sources isn't enabled.
Try a different monitor index
The overlay may be appearing on a screen you're not looking at. Set Monitor to 0 (primary display) and check all connected monitors.
Troubleshooting: Overlay on Wrong Monitor
Windows numbers monitors starting from 0. Your primary display is usually 0. If the overlay appears on the wrong screen:
- Open Settings → General.
- Change Monitor to
0and confirm it moves to your primary display. - Increment the number until the overlay appears on the correct screen.
Troubleshooting: Performance
High GPU usage
Reduce Target FPS in Settings → Display. For most avatar use cases, 30 FPS is indistinguishable from 60 and uses roughly half the GPU time.
Stuttering or dropped frames
- Ensure your GPU drivers are up to date.
- Check that the Spout sender is running at a stable FPS — Sprout can only display frames as fast as they arrive.
- If running multiple sources (Pro), try disabling sources you don't need.
High CPU usage
Sprout uses GPU rendering; CPU usage should be minimal. If you see unexpectedly high CPU:
- Lower Target FPS.
- Disable Hover Transparency if enabled — it requires per-pixel alpha testing.