RPG Maker zHUD 0.8

/*:
* zHUD.js
*
* @plugindesc (v0.8)
* A Zelda-esque Head-Up Display.
*
* @author dismal_science__, caethyril
*
* @help
*
* zHUD is a very rudimentary HP HUD, reminiscent to the style used in the
* Zelda series.
*
* zHUD is designed for use with single-actor games.
*
* zHUD uses a set of image files to indicate HP status.
*
*
* =[ U S A G E ]===========================================================
*
* zHUD's filename must remain "zHUD.js" in order to work properly.
*
* The example includes 33 image files, all named similarly with the
* prefix "zhud_x_hp_" and bearing the same width of "237" pixels.
*
* The first image file- "zhud_x_hp_0.png"- represents the image shown when
* HP is at its lowest.
*
* The second image file- "zhud_x_hp_128.png"- represents the image shown
* when HP is full.
*
* The 31 images in-between represent the various possible HP states, in this
* case, increasing/reducing in increments of 4.
*
* The example uses 33 images, but the plug-in can use any number of files.
* The plug-in adjusts depending on the ImgMax and LastImgSuffix parameters.
*
* For the included example, the parameter ImgMax should be set to "33" and
* LastImgSuffix should be set to "128".
*
* For this example, the ImgWidth parameter should be set to "237". 
* This may be adjusted depending on the size of the image used.
*
* Place image files in your project's IMG/PICTURES folder.
*
* During gameplay, when HP reaches a critical low, zHUD activates an
* audible warning- specified in the LowHealthSE parameter.
*
* For the example- LowHealthSE is set to "LowHPBeep", which represents the
* audio files "LowHPBeep.ogg" and "LowHPBeep.m4a".
*
* Place audio files in the project's AUDIO/SE folder.
*
* SE_Interval represents the amount of time in milliseconds between beeping. 
* It is set to "700" by default but may need to be adjusted depending on the
* length of the audio file that is used.
*
* Finally, the zActorID parameter is the number of the Actor whose HP will be
* displayed.
*
* zHUD usually updates its display automatically, but in cases where this
* doesn't happen, you may need to use a script call to do it manually. 
*
* Script call: dismal_sci.zHUD.refreshHUD();
*
*
* =[ E T C . ]===========================================================
*
* zHUD is written by dismal_science__ and caethyril.
*
* zHUD is free for use in both commercial and non-commercial projects,
* as long as both authors are credited accordingly.
*
* For updates and copies of the example files mentioned in this help file,
* please check out-
*
* https://ameblo.jp/dismal-science/entry-12454556656.html
*
*
* For more of Caethyril's plug-ins, please check out-
*
* http://bit.ly/2UYQnpS
*
*
* @param Prefix
* @type text
* @desc Filename prefix, ex. "zhud_x_hp_"
* @default zhud_x_hp_
*
* @param ImgWidth
* @type number
* @desc Width of image (in pixels).
* @default 237
*
* @param ImgMax
* @type number
* @desc Total number of images.
* @default 33
*
* @param LastImgSuffix
* @type number
* @desc Suffix of last image in group.
* @default 128
*
* @param LowHealthSE
* @type file
* @dir audio/se
* @require 1
* @desc Low HP Sound Effect, place in AUDIO/SE folder.
* @default LowHPBeep
*
* @param SE_Interval
* @type number
* @desc Interval between Low HP Sound Effect beeps (in milliseconds).
* @default 700
*
* @param zActorID
* @type number
* @desc ID of Actor whose HP will be displayed.
* @default 1
*
*/

var dismal_sci = dismal_sci || {};        // Author namespace
dismal_sci.zHUD = dismal_sci.zHUD || {};    // Plugin namespace

(function($) {

    // Get parameters
    $.params = PluginManager.parameters('zHUD');
    if ($.params === undefined) throw new Error('zHUD parameters not found! Check the plugin is named correctly and try again.');

    // Define parameter variables on plugin namespace
    $.Prefix = $.params['Prefix'];
    $.ImgWidth = Number($.params['ImgWidth']);
    $.ImgMax = Number($.params['ImgMax']) - 1;
    $.LastImgSuffix = Number($.params['LastImgSuffix']);
    $.LowHealthSE = $.params['LowHealthSE'];
    $.SE_Interval = Number($.params['SE_Interval']);
    $.zActorID = Number($.params['zActorID']);

    // Other plugin variables
    $.lastHP = 0;
//    $.xRight = Graphics.boxWidth - ($.ImgWidth + 24);    // boxWidth is not set yet!
    $.xOffset = $.ImgWidth + 24;                // Alternative approach
    $.xRound = $.LastImgSuffix / $.ImgMax;

    // Round to nearest multiple of integer num
    Number.prototype.roundTo = function(num) {
        return Math.ceil(this/num) * num;
    };
   
    $.lowHP = Math.pow($.xRound,2);
    $.lowHP_SND = {name: $.LowHealthSE, volume: 90, pitch: 100, pan: 0};
   
    $.lowHP_beep = function() {
        if ($.beepInterval === undefined) {
            $.beepInterval = setInterval(function(){
                AudioManager.playSe($.lowHP_SND);
            }, $.SE_Interval);
        }
    };
   
    $.lowHP_beep_kill = function() {
        if ($.beepInterval != undefined) {
            clearInterval(this.beepInterval);
            delete this.beepInterval;
        }
    };
   
    // Display appropriate picture for HUD, via showPicture
    $.refreshHUD = function() {
            // console.log('Refreshing HUD!');
            var actor = $gameActors.actor($.zActorID);
            var calcHP = ($.LastImgSuffix * actor.hp / actor.mhp).roundTo($.xRound);
            if ($.lastHP === calcHP) return;    // Only continue if changed
            $.lastHP = calcHP;            // Remember HP
            // console.log('calculated:', calcHP, '\nlow:', $.lowHP);
            if (calcHP <= $.lowHP && calcHP > 0) {  // at or below low HP, and not dead
                $.lowHP_beep();
            } else {   // end beep in all other cases
                $.lowHP_beep_kill();
        };
            var id = 1;
            var name = $.Prefix + String(calcHP);
            var origin = 0, x = Graphics.boxWidth - $.xOffset, y = 3;
            var scaleX = 100, scaleY = 100, opacity = 255, blend = 0;
            $gameScreen.showPicture(id, name, origin, x, y, scaleX, scaleY, opacity, blend);
        };
   
    // Refresh HUD when Scene_Map loads
    var _Scene_Map_start = Scene_Map.prototype.start;
    Scene_Map.prototype.start = function() {
        _Scene_Map_start.call(this);
        // console.log('Scene_Map has started!');
        $.refreshHUD();
    };
   
    // Refresh HUD when actor gains/loses HP
    var _Game_Actor_setHp = Game_Actor.prototype.setHp;
    Game_Actor.prototype.setHp = function(value) {
        _Game_Actor_setHp.call(this, value);
        // console.log('Actor HP changed!');
        $.refreshHUD();
    };
   
})(dismal_sci.zHUD);