dInfinity

A dice roller for Android where the roll is real: every throw is a rigid-body physics simulation of the actual dice shapes, rendered in 3D. Shake the phone like you would shake a fistful of dice, and read the result off the faces that land up.

Why another dice app?

Most dice apps draw a random number and show a picture. dInfinity simulates the dice. The number you get is whatever face ends up on top after the dice tumble, collide, and settle in the tray — the same way it works on a table. That makes rolls feel honest, lets you watch the d20 wobble before it stops, and means a die is defined by its shape, not by a lookup table.

Passing one phone around the table beats passing a bag of dice around and hunting for the d12 that rolled under the couch.

The design is clickable

▶ design/dInfinity.dc.html — every v1 screen, live in the browser. Clone the repository and open the file; GitHub shows you its source, not the running prototype, and it renders from this folder with no account or sign-in of any kind.

It is not a picture of the app: the notation parser, the table capacity rule and the exact outcome graph all run, following the specification in docs/. Tap dice to build a formula and shake the phone to throw them — in the prototype, the tray's own control stands in for the shake. Type 500d6 to see it refused, 2d20kh1 + 6 for advantage. Physics is faked with a random face and a tumble; everything else is real.

design/dInfinity.dc.html	The canvas: every screen and every variant on one board — start here
design/dInfinityPhone.dc.html	The phone prototype on its own, without the board around it
design/README.md	What each file is, and what the prototype needs to run

Features

• Physics-based rolls — dice are convex rigid bodies with correct mass distribution; results come from which face lands up, not from random().
• 3D rendering of the tray and dice, seen straight down or at an angle that shows the walls — your choice — with haptics and sound on every real impact, never on a die sliding or a die at rest. The table decides what it sounds like, the die's size decides the pitch, and both switch off.
• Shake to roll — accelerometer and gyroscope drive the throw, and a shake is the only way to start one. There is no Roll button, a tap on the table throws nothing, the formula editor's key says Done and only closes the editor, and there is no setting that turns shaking off. The display stays on while the tray is in front, because a shake takes both hands and puts neither of them on the glass.
• Says what a throw is worth — the lowest, the highest and the exact average, before you shake and again beside the total.
• Power-saving mode — same physics, no rendering; just the result. The dice are still heard: the impacts the throw made are played back over a second.
• Tabletop notation — roll 3d6 + 1d20 - 4, 2d10kh1, d%, and so on, and a dice set's own dice by name: 3{skull-d6}kh1. The whole grammar is in the app under Notation, with an example on every line you can tap to try.
• Does the math — the total, the modifiers and the per-die breakdown are shown the moment the dice stop. No counting pips in the middle of a fight.
• Saved rolls — name a formula, give it an icon ("Fireball", "Sneak Attack"), put it in the field with one tap and shake. Group them per game, per character, however you like; export and import them as files, from a URL, or from a git repository holding one.
• Outcome graph — see the exact probability distribution before you roll, for a typed formula or for a handful of dice picked by tapping, with mean and standard deviation.
• Standard dice — d2, d4, d6, d8, d10, d12, d18, d20, d100 (as two d10s; d% is an alias for d100), and Fudge dice (dF), whose total carries its sign.
• Extensible dice sets — dice are defined in plain text files with optional face textures; install sets from GitHub, GitLab, Codeberg or any https link to an archive. examples/ is a working set to copy: every shape, every field commented, blank atlases to draw on.
• Exchangeable tables — swap the look of the dice tray (felt, wood, glass, your own photo) the same way you would swap a wallpaper. The tray's shape never changes: it is the phone's screen, walls at the edges.
• Safe imports — a broken or malicious dice set can fail to load, but it cannot crash the app or affect other sets.
• Your accent — the one colour the interface spends is yours to choose: six presets, or any colour from the app's own picker, pushed toward the ground it is read against until it is legible on both the light and the dark one.
• Your view of the table — look straight down at the tray, or lean the camera over and see the top and left walls. Straight down is what a new install rolls with, because on a tall phone a leaning shot spends more of the frame on the wooden rim than on the felt. It is a camera either way: the dice are still drawn in perspective and still cast their shadows. A throw puts the formula and the dice menu away while the dice roll, and a double tap on the table clears every control off it until the next double tap.
• Readable out loud — every screen is labelled for TalkBack, including the tray and the charts, which are drawings and would otherwise be silent. Nothing is said by a colour alone: a natural 20, a dropped die, the chosen filter and the line a fair die would draw all say so in words as well. Touch targets are 48 dp — save the colour picker's sliders, which Material holds at 44 dp and which a test records — and the palette's contrast is measured in a test rather than eyeballed.
• Face designer — draw die faces with your finger, turn the die over, save the lot as a dice set of your own, and roll the die you drew.
• Statistics — count of lowest/highest results per die, averages, streaks, per-formula history. Yes, we know a natural 20 is exactly as likely as a natural 7. It still matters.
• No cocked dice, no invisible hand — nothing nudges, steers or pokes a die, and nothing throws one but you. A roll reads the dice that came to rest flat; a die that lands cocked or on another stays where it lies, the screen says so, and your next shake throws that die again — only that one — the way you would at a real table.
• No 500d6 — a roll is refused past a hundred dice, or sooner when the dice would not fit on the table with room to tumble. Dice shrink to make room up to a point; past that the simulation would only produce nonsense, so the app says no.

Documentation

docs/ is the written specification; the prototype is the visual one. Each document below links to the screens that realise it.

Document	Contents
docs/STATUS.md	Where the project stands right now: phase, in progress, blocked, pending decisions
docs/TODO.md	Open tasks by milestone and open questions
docs/build-setup.md	Devcontainer, building, signing keys, running tests, connecting a phone over WiFi
docs/architecture.md	Module layout, tech stack, data flow, key decisions
docs/physics-and-rendering.md	Simulation, shake input, settling and face detection, whether the dice are fair, stacking avoidance, power-saving mode
docs/dice-notation.md	Roll formula grammar, evaluation rules, saved rolls
docs/dice-sets.md	Dice set file format, shapes, textures, installing from git forges or archive URLs, validation and sandboxing
docs/tables.md	Table (tray) geometry, capacity limits, exchangeable table looks
docs/probability.md	How the outcome graph is computed
docs/face-designer.md	Finger-drawn face textures
docs/statistics.md	What is tracked, how it is stored, privacy
docs/assets/README.md	The logo files and the die font, how both are generated from Archivo, and the font licence
docs/design-handover.md	Where the app and the prototype still differ, and the questions each side is waiting on
design/README.md	The prototype: what each file is, how to open it offline, how to keep it in step with docs/
examples/README.md	The worked dice set: a commented diceset.toml using every catalogue shape, and blank atlases to draw on

Status

Implementation. The app rolls dice on a phone, and v0.2.0 is out — a signed early release, published with its SHA-256, built from this repository by pushing a tag. Every screen is written and connected; the documents in docs/ and the prototype in design/ are still the specification, and where the two disagree one of them is a bug.

It is still 0.x because the physics is not finished: 100d4 does not reliably settle, and a hard sideways shake can run a roll out to its twelve-second cap, where it gives up rather than invent an answer. See docs/STATUS.md for where things stand and docs/TODO.md for what is next.

Building

Everything happens in the devcontainer — it carries the JDK, the Android SDK, Gradle and the linters, and nothing is expected on the host but Docker. Open the repository in a devcontainer-aware editor, or:

docker build -t dinfinity-dev .devcontainer
docker run --rm -it -v "$PWD":/workspace -w /workspace dinfinity-dev \
  ./gradlew build test lint detekt ktlintCheck assembleDebugAndroidTest

Release and debug APKs land in app/build/outputs/named-apk/<variant>/ as dInfinityApp-<version>.apk and dInfinityApp-<version>-debug.apk. The container also carries adb, so a phone attached over WiFi debugging runs the on-device tests without leaving it.

docs/build-setup.md has the details: signing keys, wireless debugging, static analysis, and what the container contains.

Contributing

The working agreements — branching, PRs, tests, releases, build naming, how the tracking files are kept tidy — are in .claude/CLAUDE.md. Read it before opening a PR.

Platform

• Targets Android 17 (API 37); minSdk is 36, because Robolectric cannot start API 37 — decision 17 in docs/architecture.md
• Reference device: Google Pixel 10a; that is where it is tested first
• Kotlin, Jetpack Compose
• Accessibility: TalkBack labels on every screen, 48 dp touch targets, no meaning carried by colour alone, and WCAG 2.2 AA contrast measured rather than assumed — the rules, the measurements and the two ratios that fall short are in docs/architecture.md. Rolling needs a hand that can shake the phone. There is no other way to start a roll — no button, no key and no accessibility action — so somebody who cannot shake a phone cannot roll in this app. That is a decided limitation, not an oversight (decision 66)
• Language: English, and only English ships. Every word a screen says is a string resource, so nothing in the app stands between here and a translation somebody writes — the rule, where the line between text and a test tag is drawn, and the check that enforces it are in docs/architecture.md
• 3D rendering and physics run on-device; the app works fully offline. Network access is only used when you explicitly install a dice set, a table or a saved-roll collection from a URL.

Security

The app installs dice sets other people wrote, and that is the whole attack surface worth caring about. SECURITY.md sets out the threat model, the defences, and how to report a vulnerability privately.

License

GPL-2.0-or-later. See LICENSE.

Dice sets, tables and saved-roll collections you create with the app are yours; the app does not impose a license on them. Sets downloaded from the internet carry whatever license their author chose, shown in the set details.