ElytraUtils

A Fabric companion mod that turns CoordinatesDisplay's HUD into a proper elytra flight instrument panel — a fighter-jet-style attitude display, impact damage prediction, glide range, and a "bingo fuel" durability warning, all derived from Minecraft's actual flight physics rather than eyeballed guesses.

Flight instrument HUD

While gliding, a screen-centered attitude display appears — a real HUD, not a text readout:

• Pitch ladder — horizon-referenced climb/dive rungs (10° apart), with green/red reference brackets at the derived ideal rocket-climb angle (-34°) and the dive-caution threshold (+30°).
• Boresight — a fixed waterline marker showing where your nose actually points.
• Flight path marker — a small floating reticle showing where you're actually going (your velocity vector), independent of where you're looking. The gap between it and the boresight is your angle of attack.
• AoA indexer — a compact vertical tape reading out angle of attack directly, with a STALL flag grounded in the real airspeed floor (~0.35 blocks/tick), not a guessed angle.
• Bearing tape — a compass heading strip across the top.
• Airspeed tape — horizontal speed, scaled to blocks/second.
• Altitude tape — barometric altitude (BALT) on a scrolling tape, with a radar altitude (RALT) box beneath it that reads "no lock" instead of faking a number when there's nothing to bounce a ray off.

Every rung, bracket, and threshold on the display comes from the same decompiled-and-simulated vanilla physics as the text HUD below — see agents.md if you want the derivations.

The whole display fades out — rather than hard-clipping — as it approaches a configurable "immersive HUD height," so it reads like a real HUD's limited glass instead of painting over your whole screen. Scale, color (with alpha, for a HUD-brightness-style transparency control), and every individual element are independently configurable or toggleable, and the display runs independently of the text HUD below — turn either one off without affecting the other.

The instruments can also be held back until you're actually up at altitude: Min Radar Altitude hides them below a configured raycast (radar) AGL height, so they don't clutter the screen right at launch or landing. With Sticky Enable on, once you've climbed above that height during a flight the display stays on even if you dip back below it — e.g. buzzing the treetops after already climbing out — until you land and take off again.

Hotkeys

Two hotkeys, unbound by default (bind them in Options → Controls → ElytraUtils):

• Toggle Immersive HUD — flips Show Flight Instruments.
• Toggle Text HUD — flips Show Elytra Overlay.

Both just flip the same setting the config screen controls — they don't change when a display is allowed to show (still gated by fall-flying, or elytra-equipped-with-rockets for the text HUD). If you press one while that condition isn't currently met (so nothing on screen would otherwise change), a fading center-screen message confirms it anyway: green "... Enabled" or red "... Disabled", reflecting whichever way it actually just toggled.

Text HUD row

While gliding — or while standing on the ground with an elytra equipped and rockets in hand (pre-launch) — extra rows appear attached to the CoordinatesDisplay overlay:

Elytra  -18.4°  ✓ GLIDE  Vy -0.18  H 1.24
  Impact H:2.5❤ V:0.0❤
  Range 342 blocks
  Time to ground ~1:12

Flight line

The status indicator, with derived optimal angles:

The gradient arrows (▲ pitch up / ▼ pitch down / ● on target) tell you which way to correct toward the optimal angle for that regime. The same physics-derived colors and thresholds drive the flight instrument HUD above.

Impact line

Predicted damage in hearts if you hit something right now, accounting for your actual armor enchantments:

• H — horizontal wall-splat damage (reduced by Protection).
• V — vertical ground-impact damage (reduced by Protection and Feather Falling — Feather Falling correctly does not reduce wall impacts).

Range & Time to ground

Distance and time until you meet the ground at the current glide slope, using the configured altimeter mode (see below). Both hide themselves when you're not descending.

Time to ground is two-phase accurate, not a naive straight-line extrapolation: if your elytra will break from durability loss before you'd otherwise land, it simulates the actual post-break free-fall physics for the remaining distance instead of pretending the glide rate holds all the way down. When durability is genuinely the limiting factor, the number flashes red on the same clock as Master Caution — so turning Master Caution's banner off doesn't cost you the warning, it just moves to this row.

Master Caution

A screen-centered, slowly-flashing (epilepsy-safe 1 Hz) ELYTRA DESTRUCTION IMMINENT warning that fires when your elytra will break from durability loss before you reach the ground — i.e. you'd fall to your death mid-flight. It's a "bingo fuel" style time-vs-time comparison, so it isn't fooled by rocket-boost speed spikes.

Configuration

Configure in-game via ModMenu (optional), or edit config/coordinatesdisplay_elytrautils.json. The in-game screen groups settings under headings matching the sections below.

General

Master Caution

Altimeter

The dimension-aware reference isn't just a flat sea level everywhere:

• Overworld — vanilla sea level (63).
• Nether — the lava sea's level while below the bedrock ceiling; once you're flying above the roof (Y > 127), the reference switches to the roof itself, since the lava far below is irrelevant up there.
• End — there's no meaningful "sea level" (the world-gen value is just a noise-shaping parameter, not a surface), so this tracks the height of whichever island you were last actually over, rather than a fixed number.

HUD Lines

Flight Instruments

Requirements

• Minecraft 1.21.11, Fabric Loader 0.19.2+
• CoordinatesDisplay 19.x
• BoxLib 20.x (CoordinatesDisplay's own dependency)
• Fabric API
• ModMenu — optional, only for the in-game config screen

Build & dev deploy

./gradlew build          # -> build/libs/coordinatesdisplay-elytrautils-fabric-<version>.jar

cp .env.example .env, edit the paths, then use the "Build & Deploy to Dev Instance" editor task to build and copy the jar straight into your PrismLauncher instance's mods/ folder.

Publishing

./scripts/release.sh 1.0.0

Cuts a GitHub release; also publishes to Modrinth/CurseForge when the MODRINTH_PROJECT_ID / CURSEFORGE_PROJECT_ID repo variables are set.

Scaffolded from modrinth-curseforge-repo-template. See agents.md for the architecture and conventions. configurable "immersive HUD height," so it reads like a real HUD's limited glass instead of painting over your whole screen. Scale, color (with alpha, for a HUD-brightness-style transparency control), and every individual element are independently configurable or toggleable, and the display runs independently of the text HUD below — turn either one off without affecting the other.

Text HUD row

While gliding — or while standing on the ground with an elytra equipped and rockets in hand (pre-launch) — extra rows appear attached to the CoordinatesDisplay overlay:

Elytra  -18.4°  ✓ GLIDE  Vy -0.18  H 1.24
  Impact H:2.5❤ V:0.0❤
  Range 342 blocks
  Time to ground ~1:12

Flight line

The status indicator, with derived optimal angles:

The gradient arrows (▲ pitch up / ▼ pitch down / ● on target) tell you which way to correct toward the optimal angle for that regime. The same physics-derived colors and thresholds drive the flight instrument HUD above.

Impact line

Predicted damage in hearts if you hit something right now, accounting for your actual armor enchantments:

• H — horizontal wall-splat damage (reduced by Protection).
• V — vertical ground-impact damage (reduced by Protection and Feather Falling — Feather Falling correctly does not reduce wall impacts).

Range & Time to ground

Distance and time until you meet the ground at the current glide slope, using the configured altimeter mode (see below). Both hide themselves when you're not descending.

Master Caution

A screen-centered, slowly-flashing (epilepsy-safe 1 Hz) ELYTRA DESTRUCTION IMMINENT warning that fires when your elytra will break from durability loss before you reach the ground — i.e. you'd fall to your death mid-flight. It's a "bingo fuel" style time-vs-time comparison, so it isn't fooled by rocket-boost speed spikes.

Configuration

Configure in-game via ModMenu (optional), or edit config/coordinatesdisplay_elytrautils.json.

Requirements

• Minecraft 1.21.11, Fabric Loader 0.19.2+
• CoordinatesDisplay 19.x
• BoxLib 20.x (CoordinatesDisplay's own dependency)
• Fabric API
• ModMenu — optional, only for the in-game config screen

Build & dev deploy

./gradlew build          # -> build/libs/coordinatesdisplay-elytrautils-fabric-<version>.jar

cp .env.example .env, edit the paths, then use the "Build & Deploy to Dev Instance" editor task to build and copy the jar straight into your PrismLauncher instance's mods/ folder.

Publishing

./scripts/release.sh 1.0.0

Cuts a GitHub release; also publishes to Modrinth/CurseForge when the MODRINTH_PROJECT_ID / CURSEFORGE_PROJECT_ID repo variables are set.

Scaffolded from modrinth-curseforge-repo-template. See agents.md for the architecture and conventions.