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         next: function(){
 117                 if (this.currentid < this.vimgs.length-1) {
 118                         this.show(this.currentid+1);
 119                 } else {
 120                         alert('show.next called beyond last element');
 121                 }
 122         },
 123
 124         exit: function(){
 125                 if (this.isplaying) { $clear(this.timer); }
 126                 this.prevdisplay.setStyle('display', 'none');
 127                 this.ondisplay.setStyle('display', 'none');
 128                 this.stopfx();
 129                 this.options.cbExit();
 130         },
 131
 132         comm: function(){
 133                 /* alert('show.comm called, do nothing'); */
 134         },
 135
 136         /* Entry point: called to start doing things */
 137
 138         start: function(id, play){
 139                 this.options.cbStart();
 140                 this.isplaying = play;
 141                 this.controls.running(this.isplaying);
 142                 this.show(id);
 143                 return false; /* to make it usable from href links */
 144         },
 145
 146         /* "Private" methods to do the real job */
 147
 148         show: function(id){
 149                 /* alert('called show.show('+id+')'); */
 150                 this.currentid = id;
 151                 var newcache = {
 152                         prev: (id > 0)?this.prepare(id-1):{},
 153                         curr: this.prepare(id),
 154                         next: (id < (this.vimgs.length-1))?this.prepare(id+1):{},
 155                 };
 156                 delete this.cache;
 157                 this.cache = newcache;
 158                 if (this.cache.curr.ready) {
 159                         this.display(this.cache.curr);
 160                 } else {
 161                         this.pendingload = true;
 162                         this.showloading();
 163                 }
 164                 this.controls.info(id,this.vimgs.length,
 165                                 this.vimgs[id][0],
 166                                 this.vimgs[id][1]);
 167         },
 168
 169         prepare: function(id){
 170                 var vi;
 171                 for (vi=0;vi<this.vimgs[id][2].length-1;vi++) {
 172                         if ((this.vimgs[id][2][vi][0] >= this.target.width) ||
 173                             (this.vimgs[id][2][vi][1] >= this.target.height)) {
 174                                 break;
 175                         }
 176                 }
 177                 /* alert('prepare id='+id+', selected '+vi+' at '+
 178                         this.vimgs[id][2][vi][0]+'x'+
 179                         this.vimgs[id][2][vi][1]); */
 180                 var cachel;
 181                 ['prev', 'curr', 'next'].each(function(el){
 182                         if (this.cache[el] &&
 183                             this.cache[el].id == id &&
 184                             this.cache[el].vi == vi) {
 185                                 cachel = this.cache[el];
 186                         }
 187                 }.bind(this));
 188                 if (! cachel) {
 189                         cachel = {
 190                                 id: id,
 191                                 vi: vi,
 192                                 ready: false,
 193                                 url: this.vimgs[id][2][vi][2],
 194                         };
 195                         cachel.img = this.bgload(cachel);
 196                 }
 197                 return cachel;
 198         },
 199
 200         bgload: function(cachel){
 201                 /* alert('bgload: id='+cachel.id+' vi='+cachel.vi+
 202                         ' url='+cachel.url); */
 203                 return new Asset.image(this.vimgs[cachel.id][2][cachel.vi][2],{
 204                         id: this.vimgs[cachel.id][0],
 205                         title: this.vimgs[cachel.id][1],
 206                         onload: this.loadcomplete.bind(this,[cachel]),
 207                 });
 208         },
 209
 210         loadcomplete: function(cachel){
 211                 /* alert('loadcomplete '+cachel.url+' id='+cachel.id+
 212                         ' vi='+cachel.vi); */
 213                 cachel.ready = true;
 214                 if (cachel.id == this.currentid &&
 215                     this.pendingload) {
 216                         this.pendingload = false;
 217                         this.hideloading();
 218                         this.display(cachel);
 219                 }
 220         },
 221
 222         display: function(cachel){
 223                 var newstyle = this.calcsize(cachel);
 224                 var newimg = cachel.img.clone();
 225                 newimg.setStyles(newstyle);
 226                 newimg.setStyles({
 227                         zIndex: 3,
 228                         opacity: 0,
 229                 });
 230                 this.prevdisplay.dispose();
 231                 this.prevdisplay = this.ondisplay.clone().
 232                 setStyle('zIndex', 2).injectInside(this.container.container);
 233                 newimg.replaces(this.ondisplay);
 234                 this.ondisplay = newimg;
 235                 this.effect();
 236         },
 237
 238         effect: function(){
 239                 this.fx = new Fx.Tween(this.ondisplay, {
 240                         duration: this.options.fxduration,
 241                 });
 242                 this.fx.addEvent('complete',this.displaycomplete.bind(this));
 243                 this.fx.start('opacity', 0, 1);
 244         },
 245
 246         displaycomplete: function(){
 247                 this.prevdisplay.setStyle('display', 'none');
 248                 if (this.isplaying) {
 249                         this.timer = this.autonext.delay(this.delay,this);
 250                 }
 251         },
 252
 253         autonext: function(){
 254                 if (this.isplaying) {
 255                         if (this.currentid < this.vimgs.length-1) {
 256                                 this.show(this.currentid+1);
 257                         } else {
 258                                 this.exit();
 259                         }
 260                 }
 261         },
 262
 263         calcsize: function(cachel){
 264                 var factor = 1;
 265                 var candidate;
 266                 candidate = this.target.width /
 267                                 this.vimgs[cachel.id][2][cachel.vi][0];
 268                 if (factor > candidate) { factor = candidate; }
 269                 candidate = this.target.height /
 270                                 this.vimgs[cachel.id][2][cachel.vi][1];
 271                 if (factor > candidate) { factor = candidate; }
 272                 var w = Math.round(this.vimgs[cachel.id][2][cachel.vi][0] *
 273                         factor);
 274                 var h = Math.round(this.vimgs[cachel.id][2][cachel.vi][1] *
 275                         factor);
 276                 var t = Math.round((this.coords.height-h)/2);
 277                 var l = Math.round((this.coords.width-w)/2);
 278                 /* alert('new size: '+w+'x'+h+'+'+l+'+'+t); */
 279                 return {
 280                         position: 'absolute',
 281                         top: t+'px',
 282                         left: l+'px',
 283                         width: w,
 284                         height: h,
 285                 };
 286         },
 287
 288         showloading: function(){
 289                 this.loadingdiv.setStyle('display', 'block');
 290         },
 291
 292         hideloading: function(){
 293                 this.loadingdiv.setStyle('display', 'none');
 294         },
 295
 296         stopfx: function(){
 297                 if (this.fx) this.fx.cancel();
 298         },
 299
 300         updatecoords: function(){
 301                 this.coords = this.container.getCoordinates();
 302                 this.target = {
 303                         width: Math.round(this.coords.width *
 304                                                 this.options.percentage / 100),
 305                         height: Math.round(this.coords.height *
 306                                                 this.options.percentage / 100),
 307                 };
 308                 /* alert('coords: '+this.coords.width+'x'+this.coords.height+
 309                      ', target: '+this.target.width+'x'+this.target.height); */
 310         },
 311
 312 });
 313 Show.implement(new Options);
 314 Show.implement(new Events);
 315