====== HP Bar (Icon) ======
=====Finished Product=====
{{:developer_center:developer_editor:202507251447.mp4?nolink&400|}}
===== UI Design=====
{{:developer_center:developer_editor:screenshot_1753428785.png?nolink|}}

===== Script =====
<code LUA>
local UI_ID = nil
local HEART_TEXT_ID = nil

local FULL_HEART = "◆"
local EMPTY_HEART = "◇"

local function UpdateHeartText(e)
  local pid = e.eventobjid
  local attr = e.playerattr

  if attr == PLAYERATTR.CUR_HP then
    local _, cur = Player:getAttr(pid, PLAYERATTR.CUR_HP)
    local _, max = Player:getAttr(pid, PLAYERATTR.MAX_HP)
    if max <= 0 then max = 1 end

    local percent = cur / max
    local hearts = math.floor(percent * 10 + 0.0001)

    local text = ""
    for i = 1, 10 do
      if i <= hearts then
        text = text .. FULL_HEART
      else
        text = text .. EMPTY_HEART
      end
    end

    Customui:setText(pid, UI_ID, HEART_TEXT_ID, text)
  end
end

ScriptSupportEvent:registerEvent("Game.AnyPlayer.EnterGame", UpdateHeartText)
ScriptSupportEvent:registerEvent("Player.ChangeAttr", UpdateHeartText)
</code>

=====Explanation =====
==== Global Variables: ====

<code LUA>
local UI_ID = nil
local HEART_TEXT_ID = nil
</code>
These variables are placeholders for the custom UI components:

  * **UI_ID**: The ID of the custom UI interface.
  * **HEART_TEXT_ID**: The ID of the text component within the UI that will display the health bar. 
==== Heart Representation (Text-based):====
<code LUA>
local FULL_HEART = "◆"
local EMPTY_HEART = "◇"
</code>
These are just visual symbols to represent health:
  * FULL_HEART: Symbol for full/active health.
  * EMPTY_HEART: Symbol for missing/empty health.

==== Function: UpdateHeartText(e) ====
This function updates the UI text based on the player's current health.

**1. Extract player information from event:**
<code LUA>
local pid = e.eventobjid
local attr = e.playerattr
</code>
  * **pid:** The ID of the player whose data is changing.
  * **attr:** The specific attribute that changed (like health).

**2. Only proceed if the attribute is current health:**
<code LUA>
if attr == PLAYERATTR.CUR_HP then
</code>
Ensures this logic runs only when health has changed.

**3. Fetch current and max HP:**
<code LUA>
local _, cur = Player:getAttr(pid, PLAYERATTR.CUR_HP)
local _, max = Player:getAttr(pid, PLAYERATTR.MAX_HP)
</code>
Retrieves the player's current and maximum health values.
<code LUA>
if max <= 0 then max = 1 end
</code>
Prevents division by zero in case max HP is 0 or invalid.

**4. Calculate percentage and number of full hearts:**
<code LUA>
local percent = cur / max
local hearts = math.floor(percent * 10 + 0.0001)
</code>
Calculates the ratio of current health to maximum health.

Scales it to a 10-point scale (like 10 hearts).

The + 0.0001 helps prevent rounding errors.

**5. Build the heart bar as a text string:**
<code LUA>
local text = ""
for i = 1, 10 do
  if i <= hearts then
    text = text .. FULL_HEART
  else
    text = text .. EMPTY_HEART
  end
end
</code>
Loops through 10 positions:

Adds a full heart if the player has that much health.

Otherwise, adds an empty heart.

**Update the UI:**
<code LUA>
Customui:setText(pid, UI_ID, HEART_TEXT_ID, text)
</code>

Displays the generated text (heart bar) on the player's custom UI.

==== Event Registration: ====

<code LUA>
ScriptSupportEvent:registerEvent("Game.AnyPlayer.EnterGame", UpdateHeartText)
ScriptSupportEvent:registerEvent("Player.ChangeAttr", UpdateHeartText)
</code>

These lines ensure that the UpdateHeartText function is called:

When any player enters the game.

When a player's attributes change (like losing or gaining health).

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