Heartbeat Immersion

## What it does

Heartbeat Immersion gives your character a pulse.

At full health you can barely hear it - a slow, quiet thump somewhere in the
background. As you take damage it creeps up on you: faster, louder, heavier.
When you are one hit away from death it is pounding in your ears.

It was built for Classic Era Hardcore, where that last sliver of health
actually means something. No numbers, no warnings, no spam - just the feeling
that your character is in trouble.

## Not just a low-health alarm

Most health-sound addons flip between two or three preset stages: fine, hurt,
danger. This one doesn't. The tempo scales **continuously** with your health,
from a calm 45 BPM down to a frantic 160 BPM, following a curve rather than a
staircase. Between 100% and 70% you will hardly register it. Below 30% it gets
insistent. Below 15% it is genuinely stressful.

Damage spikes are smoothed out, so a big crit ramps the pulse up over about a
second instead of snapping to it. It feels like a body reacting, not a meter
updating.

## The on-screen heart

There is an optional heart on your screen that beats in sync with the sound.
Drag it wherever you like and lock it in place. At full health it sits there
pale and unobtrusive. As your health drops it deepens in colour and pulses
harder, perfectly in rhythm with what you hear. Colour, size and position are
all yours - and the whole thing scales smoothly, no steps.

Want sound only? Turn the heart off in the options.

## Options

Everything is configured through a proper options window - click the heart icon
on your minimap. No commands to memorise.

- **Volume** - with a preview beat so you can dial it in by ear
- **Heart colour** - full colour picker (pale at full HP, intense when low)
- **Heart size** - 16 to 128 px
- **Unlock / lock** the heart's position - drag it anywhere
- **Show / hide** the heart
- **Only in combat** - silence it while you're just running around
- **Master or SFX channel** - Master keeps it audible even with game sound off,
  SFX respects your normal sound sliders
- **Test button** - simulates your HP dropping from 100% to 3% over 20 seconds
  so you can hear and see the whole range without getting hit

Slash commands `/hbi` and `/heartbeat` open the same window if you prefer typing.

## Hardcore-safe

The addon reads one thing: your own health. It does not automate anything, does
not react to anything else in the world, and gives you no information the game
doesn't already show you on your health bar. It just makes you feel it.

## Sound

All audio is original and synthesised from scratch for this addon - no sampled
or third-party material. The heartbeat is layered as two damped low-frequency
thumps with a pitch glide, shipped as 20 pre-rendered loudness steps, because
WoW's sound API has no per-sound volume parameter. Combined with the fully
continuous tempo, it reads as a smooth ramp to the ear rather than as stages.

## Supported clients

Built and tested for all Wow Clients (Retail, MoP, TBC, Classic). The code only uses
APIs that exist across every WoW client, and ships TOC files for TBC Anniversary,
MoP Classic and Retail as well.

## Feedback

Bug reports and ideas are welcome in the comments.