include/show.js

   1 /*
   2         $Id$
   3
   4         This is a part of mkgallery.pl suite
   5         http://www.average.org/mkgallery/
   6
   7         Uses mootools (1.2) http://www.mootools.net/
   8         Inspired by slideshow http://www.phatfusion.net/slideshow/
   9 */
  10
  11 /*
  12         Slideshow
  13
  14   - On show image: find this and next urls; put in place
  15     those that are already here; free unneeded; initiate download of
  16     the rest; if needed image is ready then initiate "transitioning", else
  17     initiate "loading".
  18   - On load complete: if this is the target image, initiate "transitioning".
  19   - On "loading": show "loading" image
  20   - On "transitioning": hide "loading" image; initiate FX animation to the
  21     needed image.
  22   - On animation complete: blank previous image; if "playing" then schedule
  23     autoswitch to next image in the future.
  24   - On autoswitch to next image: if "playing" then switch to next image.
  25   - On switch to next image: if next exists, show next image, else show
  26     "last image" message.
  27   - On switch to prev image: if prev exists, show prev image, else show
  28     "first image" message.
  29   - On "play": make "playing"; switch to next image.
  30   - On "stop": if "playing" cancel autoswitch; break "playing".
  31   - On "start show": set up things; set "playing" state; show needed image.
  32   - On "stop show": cancel any schedules, hide things.
  33   - On resize: recalculate existing image size and position; determine
  34     what image is needed; if it is not the one on display then request
  35     "show image" for the new image.
  36 */
  37
  38 var Show = new Class({
  39
  40         getOptions: function(){
  41                 return {
  42                         cbStart: function(){ alert('show start undefined'); },
  43                         cbExit: function(){ alert('show exit undefined'); },
  44                         percentage: 98,
  45                         delay: 5000,
  46                         fxduration: 200,
  47                 }
  48         },
  49
  50         initialize: function(vimgs, container, controls, options){
  51                 this.setOptions(this.getOptions(), options);
  52                 this.vimgs = vimgs;
  53                 this.container = container;
  54                 this.controls = controls;
  55                 this.controls.registershow(this);
  56                 this.timer = 0;
  57                 this.delay = this.options.delay;
  58                 this.cache = {
  59                         prev: {},
  60                         curr: {},
  61                         next: {},
  62                 };
  63                 this.updatecoords();
  64                 this.prevdisplay = new Element('img').
  65                         setStyle('opacity', 0).
  66                         injectInside(this.container.container);
  67                 this.ondisplay = new Element('img').
  68                         setStyle('opacity', 0).
  69                         injectInside(this.container.container);
  70                 this.loadingdiv = new Element('div').
  71                 addClass('loading').setStyles({
  72                         position: 'absolute',
  73                         top: 0,
  74                         left: 0,
  75                         zIndex: 4,
  76                         display: 'none',
  77                         width: this.coords.width,
  78                         height: this.coords.height,
  79                 }).injectInside(this.container.container);
  80
  81                 window.addEvent('resize', this.resizer.bind(this))
  82         },
  83
  84         /* event handler for window resize */
  85
  86         resizer: function(){
  87                 this.updatecoords();
  88                 var newstyle = this.calcsize(this.cache.curr);
  89                 this.ondisplay.setStyles(newstyle);
  90                 /* check if we need reload */
  91         },
  92
  93         /* prev, play, stop, next, exit, comm are methods for button presses */
  94
  95         prev: function(){
  96                 if (this.currentid > 0) {
  97                         this.show(this.currentid-1);
  98                 } else {
  99                         /* alert('show.prev called beyond first element'); */
 100                 }
 101         },
 102
 103         stop: function(){
 104                 if (this.isplaying) { $clear(this.timer); }
 105                 this.isplaying = false;
 106                 $clear(this.timer);
 107                 this.controls.running(0);
 108         },
 109
 110         play: function(){
 111                 this.isplaying = true;
 112                 this.timer = this.autonext.delay(this.delay,this);
 113                 this.controls.running(1);
 114         },
 115
 116         toggleplay: function(){
 117                 if (this.isplaying) { this.stop(); }
 118                 else { this.play(); }
 119         },
 120
 121         next: function(){
 122                 if (this.currentid < this.vimgs.length-1) {
 123                         this.show(this.currentid+1);
 124                 } else {
 125                         /* alert('show.next called beyond last element'); */
 126                 }
 127         },
 128
 129         exit: function(){
 130                 if (this.isplaying) { $clear(this.timer); }
 131                 this.prevdisplay.setStyle('display', 'none');
 132                 this.ondisplay.setStyle('display', 'none');
 133                 this.stopfx();
 134                 this.options.cbExit();
 135         },
 136
 137         comm: function(){
 138                 /* alert('show.comm called, do nothing'); */
 139         },
 140
 141         /* Entry point: called to start doing things */
 142
 143         start: function(id, play){
 144                 this.options.cbStart();
 145                 this.isplaying = play;
 146                 this.controls.running(this.isplaying);
 147                 this.updatecoords();
 148                 this.show(id);
 149                 return false; /* to make it usable from href links */
 150         },
 151
 152         /* "Private" methods to do the real job */
 153
 154         show: function(id){
 155                 /* alert('called show.show('+id+')'); */
 156                 this.currentid = id;
 157                 var newcache = {
 158                         prev: (id > 0)?this.prepare(id-1):{},
 159                         curr: this.prepare(id),
 160                         next: (id < (this.vimgs.length-1))?this.prepare(id+1):{},
 161                 };
 162                 delete this.cache;
 163                 this.cache = newcache;
 164                 if (this.cache.curr.ready) {
 165                         this.display(this.cache.curr);
 166                 } else {
 167                         this.pendingload = true;
 168                         this.showloading();
 169                 }
 170                 this.controls.info(id,this.vimgs.length,
 171                                 this.vimgs[id][0],
 172                                 this.vimgs[id][1]);
 173         },
 174
 175         prepare: function(id){
 176                 var vi;
 177                 for (vi=0;vi<this.vimgs[id][2].length-1;vi++) {
 178                         if ((this.vimgs[id][2][vi][0] >= this.target.width) ||
 179                             (this.vimgs[id][2][vi][1] >= this.target.height)) {
 180                                 break;
 181                         }
 182                 }
 183                 /* alert('prepare id='+id+', selected '+vi+' at '+
 184                         this.vimgs[id][2][vi][0]+'x'+
 185                         this.vimgs[id][2][vi][1]); */
 186                 var cachel;
 187                 ['prev', 'curr', 'next'].each(function(el){
 188                         if (this.cache[el] &&
 189                             this.cache[el].id == id &&
 190                             this.cache[el].vi == vi) {
 191                                 cachel = this.cache[el];
 192                         }
 193                 }.bind(this));
 194                 if (! cachel) {
 195                         cachel = {
 196                                 id: id,
 197                                 vi: vi,
 198                                 ready: false,
 199                                 url: this.vimgs[id][2][vi][2],
 200                         };
 201                         cachel.img = this.bgload(cachel);
 202                 }
 203                 return cachel;
 204         },
 205
 206         bgload: function(cachel){
 207                 /* alert('bgload: id='+cachel.id+' vi='+cachel.vi+
 208                         ' url='+cachel.url); */
 209                 return new Asset.image(this.vimgs[cachel.id][2][cachel.vi][2],{
 210                         id: this.vimgs[cachel.id][0],
 211                         title: this.vimgs[cachel.id][1],
 212                         onload: this.loadcomplete.bind(this,[cachel]),
 213                 });
 214         },
 215
 216         loadcomplete: function(cachel){
 217                 /* alert('loadcomplete '+cachel.url+' id='+cachel.id+
 218                         ' vi='+cachel.vi); */
 219                 cachel.ready = true;
 220                 if (cachel.id == this.currentid &&
 221                     this.pendingload) {
 222                         this.pendingload = false;
 223                         this.hideloading();
 224                         this.display(cachel);
 225                 }
 226         },
 227
 228         display: function(cachel){
 229                 var newstyle = this.calcsize(cachel);
 230                 var newimg = cachel.img.clone();
 231                 newimg.setStyles(newstyle);
 232                 newimg.setStyles({
 233                         zIndex: 3,
 234                         opacity: 0,
 235                 });
 236                 this.prevdisplay.dispose();
 237                 this.prevdisplay = this.ondisplay.clone().
 238                 setStyle('zIndex', 2).injectInside(this.container.container);
 239                 newimg.replaces(this.ondisplay);
 240                 this.ondisplay = newimg;
 241                 this.effect();
 242         },
 243
 244         effect: function(){
 245                 this.fx = new Fx.Tween(this.ondisplay, {
 246                         duration: this.options.fxduration,
 247                 });
 248                 this.fx.addEvent('complete',this.displaycomplete.bind(this));
 249                 this.fx.start('opacity', 0, 1);
 250         },
 251
 252         displaycomplete: function(){
 253                 this.prevdisplay.setStyle('display', 'none');
 254                 if (this.isplaying) {
 255                         this.timer = this.autonext.delay(this.delay,this);
 256                 }
 257         },
 258
 259         autonext: function(){
 260                 if (this.isplaying) {
 261                         if (this.currentid < this.vimgs.length-1) {
 262                                 this.show(this.currentid+1);
 263                         } else {
 264                                 this.exit();
 265                         }
 266                 }
 267         },
 268
 269         calcsize: function(cachel){
 270                 var factor = 1;
 271                 var candidate;
 272                 candidate = this.target.width /
 273                                 this.vimgs[cachel.id][2][cachel.vi][0];
 274                 if (factor > candidate) { factor = candidate; }
 275                 candidate = this.target.height /
 276                                 this.vimgs[cachel.id][2][cachel.vi][1];
 277                 if (factor > candidate) { factor = candidate; }
 278                 var w = Math.round(this.vimgs[cachel.id][2][cachel.vi][0] *
 279                         factor);
 280                 var h = Math.round(this.vimgs[cachel.id][2][cachel.vi][1] *
 281                         factor);
 282                 var t = Math.round((this.coords.height-h)/2);
 283                 var l = Math.round((this.coords.width-w)/2);
 284                 /* alert('new size: '+w+'x'+h+'+'+l+'+'+t); */
 285                 return {
 286                         position: 'absolute',
 287                         top: t+'px',
 288                         left: l+'px',
 289                         width: w,
 290                         height: h,
 291                 };
 292         },
 293
 294         showloading: function(){
 295                 this.loadingdiv.setStyle('display', 'block');
 296         },
 297
 298         hideloading: function(){
 299                 this.loadingdiv.setStyle('display', 'none');
 300         },
 301
 302         stopfx: function(){
 303                 if (this.fx) this.fx.cancel();
 304         },
 305
 306         updatecoords: function(){
 307                 this.coords = this.container.getCoordinates();
 308                 this.target = {
 309                         width: Math.round(this.coords.width *
 310                                                 this.options.percentage / 100),
 311                         height: Math.round(this.coords.height *
 312                                                 this.options.percentage / 100),
 313                 };
 314                 /* alert('coords: '+this.coords.width+'x'+this.coords.height+
 315                      ', target: '+this.target.width+'x'+this.target.height); */
 316         },
 317
 318 });
 319 Show.implement(new Options);
 320 Show.implement(new Events);
 321