defs.js

"use strict";

(function(){
    var G = (window.FireGame = window.FireGame || {});
    var U = MajicUnits;
    var MG = MajicGame;
    var Bh = MG.behavior;

    G.Camera = function(x, y) {
        var mg = G.game;
        this.x = x;
        this.y = y;

        function _getAsPx(px) {
            return px instanceof U.UnitValue? px.mul( 1 ) : U.pixels( px ).relax();
        }

        Object.defineProperty(this, 'pos', {
            get: function() {
                return { x: this.x.mul(1), y: this.y.mul(1) };
            }
        });

        this.getTL = function() {
            return {
                x: this.x.sub( mg.center.x ).relax()
              , y: this.y.sub( mg.center.y ).relax()
            };
        };

        this.getBR = function() {
            return {
                x: this.x.add( mg.center.x ).relax()
              , y: this.y.add( mg.center.y ).relax()
            };
        };

        this.toCamX = function(x) {
            x = _getAsPx(x);
            return x.sub( this.getTL().x ).relax();
        }

        this.toCamY = function(y) {
            // Convert to U.pixels if necessary
            y = _getAsPx(y);
            return y.sub( this.getTL().y ).relax();
        }

        this.toGameX = function(x) {
            x = _getAsPx(x);
            return x.add( this.getTL().x ).relax();
        }

        this.toGameY = function(y) {
            // Convert to U.pixels if necessary
            y = _getAsPx(y);
            return y.add( this.getTL().y ).relax();
        }

        function boundsCheck() {
            // Adjust for out-of-bounds
            var tl = this.getTL();
            var br = this.getBR();
            var tDiff = tl.y
            var lDiff = tl.x
            var bDiff = br.y.sub( G.state.area.h ).relax();
            var rDiff = br.x.sub( G.state.area.w ).relax();
            if (bDiff > 0) {
                this.y = this.y.sub(bDiff);
                this.v = U.pixels( 0 ).per.second;
            }
            if (rDiff > 0) {
                this.x = this.x.sub(rDiff);
                this.h = U.pixels( 0 ).per.second;
            }
            if (tDiff < 0) {
                this.y = this.y.sub(tDiff);
                this.v = U.pixels( 0 ).per.second;
            }
            if (lDiff < 0) {
                this.x = this.x.sub(lDiff);
                this.h = U.pixels( 0 ).per.second;
            }
        };

        this.behavior = [
            Bh.momentum
          , Bh.thrustKeys(
                {
                  forward: ['w', 'ArrowUp']
                , back: ['s', 'ArrowDown']
                , left: ['a', 'ArrowLeft']
                , right: ['d', 'ArrowRight']
                }
              , U.pixels( 300 ).per.second.per.second
            )
          , Bh.friction(  U.pixels( 100 ).per.second.per.second  )
          , Bh.speedLimited( U.pixels( 240 ).per.second )
          , boundsCheck // (above)
        ];
    };
    G.Camera.prototype = MG.spritePrototype;
})();