cdf/src/old/scrolltext.js

A library for creating oldschool demo-like animations with JavaScript

(function (global) {
  var lib = global.cdf || {};

  var ltrobj = lib.ltrobj = function (posx, posy, ltr) {
    this.posx = posx;
    this.posy = posy;
    this.ltr = ltr;
    return this;
  };

  var sortPosx = lib.sortPosx = function (a, b) {
    var x = a.posx;
    var y = b.posx;
    return ((x < y) ? -1 : ((x > y) ? 1 : 0));
  };

  var sortPosy = lib.sortPosx = function (a, b) {
    var x = a.posy;
    var y = b.posy;
    return ((x < y) ? -1 : ((x > y) ? 1 : 0));
  };

  var scrolltext_horizontal = lib.scrolltext_horizontal = function () {
    this.scroffset = 0;
    this.oldspeed = 0;
    this.speed = 1;
    this.letters = {};
    this.scrtxt = " ";
    this.pausetimer = 0;
    this.pausedelay = 0;
    return this;
  }

  scrolltext_horizontal.prototype = {
    init: function (dst, font, speed, sinparam, type) {
      this.speed = speed;
      this.dst = dst;
      this.font = font;
      this.fontw = this.font.tilew;
      this.fonth = this.font.tileh;
      this.fontstart = this.font.tilestart;
      this.wide = Math.ceil(this.dst.canvas.width / this.fontw) + 1;
      for (i = 0; i <= this.wide; i++) {
        this.letters[i] = new ltrobj(Math.ceil((this.wide * this.fontw) + i * this.fontw), 0, this.scrtxt.charCodeAt(this.scroffset));
        this.scroffset++;
      }
      if (typeof (sinparam) != 'undefined')
        this.sinparam = sinparam;
      if (typeof (type) == 'undefined')
        this.type = 0;
      else
        this.type = type;
    },
    draw: function (posy) {
      var prov = 0;
      var temp = new Array();
      var tmp = this.dst.contex.globalAlpha;
      this.dst.contex.globalAlpha = 1;
      var oldvalue = new Array();
      var i;
      if (typeof (this.sinparam) != 'undefined') {
        for (var j = 0; j < this.sinparam.length; j++) {
          oldvalue[j] = this.sinparam[j].myvalue;
        }
      }
      if (this.speed == 0) {
        this.pausetimer += 1;
        if (this.pausetimer == 60 * this.pausedelay) {
          this.speed = this.oldspeed;
        }
      }
      var speed = this.speed;
      for (i = 0; i <= this.wide; i++) {
        this.letters[i].posx -= speed;
        if (this.letters[i].posx <= -this.fontw) {
          if (this.scrtxt.charAt(this.scroffset) == "^") {
            if (this.scrtxt.charAt(this.scroffset + 1) == "P") {
              this.pausedelay = this.scrtxt.charAt(this.scroffset + 2);
              this.pausetimer = 0;
              this.oldspeed = this.speed;
              this.speed = 0;
              this.scroffset += 3;
            } else if (this.scrtxt.charAt(this.scroffset + 1) == "S") {
              this.speed = this.scrtxt.charAt(this.scroffset + 2);
              this.scroffset += 3;
            }
            //
            // ADDON by Robert Annett
            //
            else if (this.scrtxt.charAt(this.scroffset + 1) == "C") {
              var end = this.scrtxt.indexOf(';', this.scroffset + 2);
              var functionName = this.scrtxt.substring(this.scroffset + 2, end);
              window[functionName]();
              this.scroffset += (end - this.scroffset) + 1;
            }
          } else {
            this.letters[i].posx = this.wide * this.fontw + (this.letters[i].posx + this.fontw);
            if (typeof (this.sinparam) != 'undefined') {
              for (var j = 0; j < this.sinparam.length; j++) {
                oldvalue[j] += this.sinparam[j].inc;
              }
            }
            this.letters[i].ltr = this.scrtxt.charCodeAt(this.scroffset);
            this.scroffset++;
            if (this.scroffset > this.scrtxt.length - 1)
              this.scroffset = 0;
          }
        }
      }
      if (typeof (this.sinparam) != 'undefined') {
        for (var j = 0; j < this.sinparam.length; j++) {
          this.sinparam[j].myvalue = oldvalue[j];
        }
      }

      for (j = 0; j <= this.wide; j++) {
        temp[j] = {
          indice: j,
          posx: this.letters[j].posx
        };
      }
      temp.sort(sortPosx);
      for (i = 0; i <= this.wide; i++) {
        if (typeof (this.sinparam) != 'undefined') {
          prov = 0;
          for (var j = 0; j < this.sinparam.length; j++) {
            if (this.type == 0)
              prov += Math.sin(this.sinparam[j].myvalue) * this.sinparam[j].amp;
            if (this.type == 1)
              prov += -Math.abs(Math.sin(this.sinparam[j].myvalue) * this.sinparam[j].amp);
            if (this.type == 2)
              prov += Math.abs(Math.sin(this.sinparam[j].myvalue) * this.sinparam[j].amp);

          }
        }
        this.font.drawTile(this.dst, this.letters[temp[i].indice].ltr - this.fontstart, this.letters[temp[i].indice].posx, prov + posy);

        if (typeof (this.sinparam) != 'undefined') {
          for (var j = 0; j < this.sinparam.length; j++) {
            this.sinparam[j].myvalue += this.sinparam[j].inc;
          }
        }
      }
      if (typeof (this.sinparam) != 'undefined') {
        for (var j = 0; j < this.sinparam.length; j++) {
          this.sinparam[j].myvalue = oldvalue[j] + this.sinparam[j].offset;
        }
      }
      this.dst.contex.globalAlpha = tmp;
    }
  };

  var scrolltext_vertical = lib.scrolltext_vertical = function () {
    this.scroffset = 0;
    this.oldspeed = 0;
    this.speed = 1;
    this.font;
    this.letters = new Object();
    this.scrtxt = " ";
    this.pausetimer = 0;
    this.pausedelay = 0;
    return this;
  }

  scrolltext_vertical.prototype = {
    init: function (dst, font, speed, sinparam, type) {
      this.speed = speed;
      this.dst = dst;
      this.font = font;
      this.fontw = this.font.tilew;
      this.fonth = this.font.tileh;
      this.fontstart = this.font.tilestart;
      this.wide = Math.ceil(this.dst.canvas.height / this.fonth) + 1;
      for (i = 0; i <= this.wide; i++) {
        this.letters[i] = new ltrobj(0, Math.ceil((this.wide * this.fonth) + i * this.fonth), this.scrtxt.charCodeAt(this.scroffset));
        this.scroffset++;
      }
      if (typeof (sinparam) != 'undefined')
        this.sinparam = sinparam;
      if (typeof (type) == 'undefined')
        this.type = 0;
      else
        this.type = type;
    },

    draw: function (posx) {
      var prov = 0;
      var temp = new Array();
      var tmp = this.dst.contex.globalAlpha;
      this.dst.contex.globalAlpha = 1;
      var oldvalue = new Array();
      var i;
      if (typeof (this.sinparam) != 'undefined') {
        for (var j = 0; j < this.sinparam.length; j++) {
          oldvalue[j] = this.sinparam[j].myvalue;
        }
      }
      if (this.speed == 0) {
        this.pausetimer += 1;
        if (this.pausetimer == 60 * this.pausedelay) {
          this.speed = this.oldspeed;
        }
      }
      var speed = this.speed;
      for (i = 0; i <= this.wide; i++) {
        this.letters[i].posy -= speed;
        if (this.letters[i].posy <= -this.fonth) {
          if (this.scrtxt.charAt(this.scroffset) == "^") {
            if (this.scrtxt.charAt(this.scroffset + 1) == "P") {
              this.pausedelay = this.scrtxt.charAt(this.scroffset + 2);
              this.pausetimer = 0;
              this.oldspeed = this.speed;
              this.speed = 0;
              this.scroffset += 3;
            } else if (this.scrtxt.charAt(this.scroffset + 1) == "S") {
              this.speed = this.scrtxt.charAt(this.scroffset + 2);
              this.scroffset += 3;
            }
            //
            // ADDON by Robert Annett
            //
            else if (this.scrtxt.charAt(this.scroffset + 1) == "C") {
              var end = this.scrtxt.indexOf(';', this.scroffset + 2);
              var functionName = this.scrtxt.substring(this.scroffset + 2, end);
              window[functionName]();
              this.scroffset += (end - this.scroffset) + 1;
            }
          } else {
            this.letters[i].posy = this.wide * this.fonth + (this.letters[i].posy + this.fonth);
            if (typeof (this.sinparam) != 'undefined') {
              for (var j = 0; j < this.sinparam.length; j++) {
                oldvalue[j] += this.sinparam[j].inc;
              }
            }
            this.letters[i].ltr = this.scrtxt.charCodeAt(this.scroffset);
            this.scroffset++;
            if (this.scroffset > this.scrtxt.length - 1)
              this.scroffset = 0;
          }
        }
      }
      if (typeof (this.sinparam) != 'undefined') {
        for (var j = 0; j < this.sinparam.length; j++) {
          this.sinparam[j].myvalue = oldvalue[j];
        }
      }

      for (j = 0; j <= this.wide; j++) {
        temp[j] = {
          indice: j,
          posy: this.letters[j].posy
        };
      }
      temp.sort(sortPosy);
      for (i = 0; i <= this.wide; i++) {
        if (typeof (this.sinparam) != 'undefined') {
          prov = 0;
          for (var j = 0; j < this.sinparam.length; j++) {
            if (this.type == 0)
              prov += Math.sin(this.sinparam[j].myvalue) * this.sinparam[j].amp;
            if (this.type == 1)
              prov += -Math.abs(Math.sin(this.sinparam[j].myvalue) * this.sinparam[j].amp);
            if (this.type == 2)
              prov += Math.abs(Math.sin(this.sinparam[j].myvalue) * this.sinparam[j].amp);
          }
        }
        this.font.drawTile(this.dst, this.letters[temp[i].indice].ltr - this.fontstart, prov + posx, this.letters[temp[i].indice].posy);

        if (typeof (this.sinparam) != 'undefined') {
          for (var j = 0; j < this.sinparam.length; j++) {
            this.sinparam[j].myvalue += this.sinparam[j].inc;
          }
        }
      }
      if (typeof (this.sinparam) != 'undefined') {
        for (var j = 0; j < this.sinparam.length; j++) {
          this.sinparam[j].myvalue = oldvalue[j] + this.sinparam[j].offset;
        }
      }
      this.dst.contex.globalAlpha = tmp;
    }
  };


  if(typeof module!=='undefined'&& module.exports){module.exports=lib;}else{global.cdf=lib;}
})(window);