cdf/src/old/_Image.js

A library for creating oldschool demo-like animations with JavaScript

// TODO: this must die.

var Canvas = require('./_Canvas');

var Sprite = function (imageURL) {
  var instance = this;
  this.img = new Image();
  this.img.src = imageURL;
  this.handlex = 0;
  this.handley = 0;
  this.midhandled = false;
  this.tilew = 0;
  this.tileh = 0;
  this.tilestart = 0;
  this.loaders = [];
  this.loaded = false;
  this.img.addEventListener('load', function(e){
    var w = instance.width = instance.w = this.width;
    var h = instance.height = instance.h = this.height;
    instance.cx = w / 2;
    instance.cy = h / 2;
    instance.loaded = true;
    instance.trigger('load', [e], instance);
  });
  return this;
};

Sprite.prototype = {
  initTile: function (tilew, tileh, tilestart) {
    this.tileh = tileh;
    this.tilew = tilew;
    if (typeof (tilestart) !== 'undefined')
      this.tilestart = tilestart;
    return this;
  },

  draw: function (dst, x, y, alpha, rotInDeg, scaleX, scaleY) {
    var tmp = dst.ctx.globalAlpha;
    if (typeof (alpha) === 'undefined') alpha = 1;
    dst.ctx.globalAlpha = alpha;
    if (arguments.length === 3 || arguments.length === 4)
      dst.ctx.drawImage(this.img, x - this.handlex, y - this.handley);
    else if (arguments.length === 5) {
      dst.ctx.translate(x, y);
      dst.ctx.rotate(rotInDeg * lib.utils.DEG_TO_RAD);
      dst.ctx.translate(-this.handlex, -this.handley);
      dst.ctx.drawImage(this.img, 0, 0);
      dst.ctx.setTransform(1, 0, 0, 1, 0, 0);
    } else {
      dst.ctx.translate(x, y);
      dst.ctx.rotate(rotInDeg * lib.utils.DEG_TO_RAD);
      dst.ctx.scale(scaleX, scaleY || scaleX);
      dst.ctx.translate(-this.handlex, -this.handley);
      dst.ctx.drawImage(this.img, 0, 0);
      dst.ctx.setTransform(1, 0, 0, 1, 0, 0);
    }
    dst.ctx.globalAlpha = tmp;
    return this;
  },

  drawTile: function (dst, nb, x, y, alpha, rotInDeg, w, h) {
    var tmp = dst.ctx.globalAlpha;
    if (typeof (alpha) === 'undefined') alpha = 1;
    dst.ctx.globalAlpha = alpha;
    var xw = Math.floor((nb % (this.img.width / this.tilew))) * this.tilew;
    var yw = Math.floor(nb / (this.img.width / this.tilew)) * this.tileh;
    this.drawPart(dst, x, y, xw, yw, this.tilew, this.tileh, alpha, rotInDeg, w, h);
    dst.ctx.globalAlpha = tmp;
    return this;
  },

  drawPart: function (dst, x, y, partx, party, partw, parth, alpha, rotInDeg, zx, zy) {
    if (partx < 0) {
      x -= partx / (this.midhandled === true ? 2 : 1);
      partw += partx;
      partx = 0;
    } else {
      if (!this.midhandled) {
        partw = Math.min(partw, this.img.width - partx);
      }
    }
    if (party < 0) {
      y -= party / (this.midhandled === true ? 2 : 1);
      parth += party;
      party = 0;
    } else {
      if (!this.midhandled) {
        parth = Math.min(parth, this.img.height - party);
      }
    }
    if (partw <= 0 || parth <= 0) {
      return;
    }
    var tmp = dst.ctx.globalAlpha;
    if (typeof alpha === 'undefined') alpha = 1;
    dst.ctx.globalAlpha = alpha;
    if (arguments.length === 7 || arguments.length === 8) {
      dst.ctx.translate(x, y);
      if (this.midhandled) dst.ctx.translate(-partw / 2, -parth / 2);
      else dst.ctx.translate(-this.handlex, -this.handley);
      dst.ctx.drawImage(this.img, partx, party, partw, parth, null, null, partw, parth);
      dst.ctx.setTransform(1, 0, 0, 1, 0, 0);
    } else if (arguments.length === 9) {
      dst.ctx.translate(x, y);
      dst.ctx.rotate(rotInDeg * lib.utils.DEG_TO_RAD);
      if (this.midhandled) dst.ctx.translate(-partw / 2, -parth / 2);
      else dst.ctx.translate(-this.handlex, -this.handley);
      dst.ctx.drawImage(this.img, partx, party, partw, parth, null, null, partw, parth);
      dst.ctx.setTransform(1, 0, 0, 1, 0, 0);
    } else {
      dst.ctx.translate(x, y);
      dst.ctx.rotate(rotInDeg * lib.utils.DEG_TO_RAD);
      dst.ctx.scale(zx, zy);
      if (this.midhandled) dst.ctx.translate(-partw / 2, -parth / 2);
      else dst.ctx.translate(-this.handlex, -this.handley);
      dst.ctx.drawImage(this.img, partx, party, partw, parth, null, null, partw, parth);
      dst.ctx.setTransform(1, 0, 0, 1, 0, 0);
    }
    dst.ctx.globalAlpha = tmp;
    return this;
  },

  setMidHandle: function (round) {
    var hx, hy;
    if(!this.loaded){
      return this.on('load',function(){
        this.setMidHandle();
      })

    }
    if(this.cx){
      hx = this.cx;
      hy = this.cy;
    } else { //TODO: Do we need this?
      hx = this.img.width/2;
      hy = this.img.height/2;
    }
    this.sethandle(hx, hy, round);
    this.midhandled = true;
    return this;
  },

  setHandle: function (x, y, round) {
    if(round){
      x = Math.round(x);
      x = Math.round(x);
    }
    this.handlex = x;
    this.handley = y;
    this.midhandled = false;
    return this;
  },

  print: function (dst, str, x, y, alpha, rot, w, h) {
    w = w || 1;
    for (var i = 0; i < str.length; i++) {
      this.drawTile(dst, str[i].charCodeAt(0) - this.tilestart, x + i * this.tilew * w, y, alpha, rot, w, h);
    }
    return this;
  },

  asCanvas: function(){
    var canvas = new Canvas(this.w,this.h);
    this.draw(canvas,0,0);
    return canvas;
  }
};

module.exports = Sprite;