Drop Board - Peg-Bounce Prize Board Overlay for OBS

A ball drops down a board full of pegs, bouncing off every peg it hits, and whichever cup it lands in is the prize. A winning cup throws confetti.

For viewer giveaways, forfeits and audience prize draws.

Single HTML file, no install, no account, fully offline. Drop it into an OBS Browser Source. English / 日本語 toggle.

======================
SEE IT MOVE
======================
The second image on this page is an animated GIF of a full drop: the ball bounces off the pegs, the pegs it hits light up, and it works its way down into a cup.

======================
WHAT IT DOES
======================

[ Dropping ]
- OBS source list -> "Refresh": one drop per reload (easiest)
- Or "Interact" and click the board, or press Space / Enter (R clears the history)
- ?balls=3 drops 1-8 balls at once. The balls collide with each other too

[ 3 to 10 cups, your names and your colours ]
- ?items=1st,3rd,5th,Miss,Miss,5th,3rd,1st sets the cups left to right
- ?colors= sets cup colours, ?hits= marks which cups count as a win
- The gear panel changes cups, ball count and peg rows (6-15) on the spot
- The default is 8 cups with the top prize at both edges. Names up to 10 characters, shrinking to fit

[ How the result is decided ]
- The default is pure physics: wherever the ball bounces to is the result
- It does not pile up in the middle — the small kick from every peg spreads it out well
- The edges are still harder to reach than the middle, so the good prizes go at the edges (the default layout already does that)
- ?mode=weight picks a target cup from ?weights= before release and nudges each bounce very slightly toward it

[ It keeps count ]
- How many times each prize came up is saved in the browser
- Refreshing the source and switching scenes both continue the tally
- ?reset=1 clears it, ?persist=off never saves, ?key= keeps two boards separate

[ Sound ]
- Three sounds: hitting a peg (lower the further down the board), landing in a cup, and a win
- ?sound=off to mute, ?vol=40 for volume (0-100, default 70). The gear panel has a slider too
- There is not a single byte of audio file in it. The waveforms are synthesised in the browser

[ Look & feel ]
- 4 themes (gold / fire / yume / mono) plus the default red-and-white
- ?accent= and ?color= for highlight and text colours, ?sign= for the sign board (12 chars)
- ?scale= for size (0.2-6)
- ?stats=off hides the history, ?fx=off drops the confetti and sparks, ?trail=off drops the glowing trail

======================
HOW TO USE
======================
1. Sources -> "+" -> Browser
2. Tick "Local file" -> pick tamaotoshi.html
3. Width 436 / Height 776 (?scale=1; with ?stats=off, 436 x 676 is enough)
4. The background is transparent, so it lies straight over your scene

Do NOT drag the source bigger inside OBS — it goes blurry. Raise the Browser Source width/height and use ?scale= instead.

======================
BEING STRAIGHT WITH YOU
======================
- ?mode=weight is a guide, not an exact probability. The bouncing after the target is chosen is still pure physics, so the ball occasionally lands next door. Aiming only at the left-hand cup, 27 out of 30 drops landed there (90%). The result that gets counted is always the cup the ball actually landed in, so what you see and what it counts never disagree.
- The tiny kick the ball gets from each peg uses Math.random. crypto.getRandomValues (with modulo bias removed) is used only to pick the target cup in ?mode=weight.
- It does not read your chat. There is no chat-app or API integration.
- Opening the file directly in a normal browser, the browser may keep audio muted until you click once. An OBS Browser Source plays from the start.

======================
NOTES
======================
- Code-drawn, no image or audio assets - crisp at any resolution
- It makes no external request of any kind. The font is embedded in the HTML, so no internet is needed
- Tested on current Chrome / Edge
- Streaming & commercial use OK (see the included terms)

FOR: streamers and VTubers who want the drop itself to be the show.

Found a bug or want a feature? Message me.