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                         injectInside(this.container.container);
  66                 this.ondisplay = new Element('img').
  67                         injectInside(this.container.container);
  68                 this.loadingdiv = new Element('div').
  69                 addClass('loading').setStyles({
  70                         position: 'absolute',
  71                         top: 0,
  72                         left: 0,
  73                         zIndex: 4,
  74                         display: 'none',
  75                         width: this.coords.width,
  76                         height: this.coords.height,
  77                 }).injectInside(this.container.container);
  78
  79                 window.addEvent('resize', this.resizer.bind(this))
  80         },
  81
  82         /* event handler for window resize */
  83
  84         resizer: function(){
  85                 this.updatecoords();
  86                 var newstyle = this.calcsize(this.cache.curr);
  87                 this.ondisplay.setStyles(newstyle);
  88                 /* check if we need reload */
  89         },
  90
  91         /* prev, play, stop, next, exit, comm are methods for button presses */
  92
  93         prev: function(){
  94                 if (this.currentid > 0) {
  95                         this.show(this.currentid-1);
  96                 } else {
  97                         alert('show.prev called beyond first element');
  98                 }
  99         },
 100
 101         stop: function(){
 102                 if (this.isplaying) { $clear(this.timer); }
 103                 this.isplaying = false;
 104                 $clear(this.timer);
 105                 this.controls.running(0);
 106         },
 107
 108         play: function(){
 109                 this.isplaying = true;
 110                 this.timer = this.autonext.delay(this.delay,this);
 111                 this.controls.running(1);
 112         },
 113
 114         next: function(){
 115                 if (this.currentid < this.vimgs.length-1) {
 116                         this.show(this.currentid+1);
 117                 } else {
 118                         alert('show.next called beyond last element');
 119                 }
 120         },
 121
 122         exit: function(){
 123                 if (this.isplaying) { $clear(this.timer); }
 124                 this.prevdisplay.setStyle('display', 'none');
 125                 this.ondisplay.setStyle('display', 'none');
 126                 this.stopfx();
 127                 this.options.cbExit();
 128         },
 129
 130         comm: function(){
 131                 /* alert('show.comm called, do nothing'); */
 132         },
 133
 134         /* Entry point: called to start doing things */
 135
 136         start: function(id, play){
 137                 this.options.cbStart();
 138                 this.isplaying = play;
 139                 this.controls.running(this.isplaying);
 140                 this.show(id);
 141                 return false; /* to make it usable from href links */
 142         },
 143
 144         /* "Private" methods to do the real job */
 145
 146         show: function(id){
 147                 /* alert('called show.show('+id+')'); */
 148                 this.currentid = id;
 149                 var newcache = {
 150                         prev: (id > 0)?this.prepare(id-1):{},
 151                         curr: this.prepare(id),
 152                         next: (id < (this.vimgs.length-1))?this.prepare(id+1):{},
 153                 };
 154                 delete this.cache;
 155                 this.cache = newcache;
 156                 if (this.cache.curr.ready) {
 157                         this.display(this.cache.curr);
 158                 } else {
 159                         this.pendingload = true;
 160                         this.showloading();
 161                 }
 162                 this.controls.info(id,this.vimgs.length,
 163                                 this.vimgs[id][0],
 164                                 this.vimgs[id][1]);
 165         },
 166
 167         prepare: function(id){
 168                 var vi;
 169                 for (vi=0;vi<this.vimgs[id][2].length-1;vi++) {
 170                         if ((this.vimgs[id][2][vi][0] >= this.target.width) ||
 171                             (this.vimgs[id][2][vi][1] >= this.target.height)) {
 172                                 break;
 173                         }
 174                 }
 175                 /* alert('prepare id='+id+', selected '+vi+' at '+
 176                         this.vimgs[id][2][vi][0]+'x'+
 177                         this.vimgs[id][2][vi][1]); */
 178                 var cachel;
 179                 ['prev', 'curr', 'next'].each(function(el){
 180                         if (this.cache[el] &&
 181                             this.cache[el].id == id &&
 182                             this.cache[el].vi == vi) {
 183                                 cachel = this.cache[el];
 184                         }
 185                 }.bind(this));
 186                 if (! cachel) {
 187                         cachel = {
 188                                 id: id,
 189                                 vi: vi,
 190                                 ready: false,
 191                                 url: this.vimgs[id][2][vi][2],
 192                         };
 193                         cachel.img = this.bgload(cachel);
 194                 }
 195                 return cachel;
 196         },
 197
 198         bgload: function(cachel){
 199                 /* alert('bgload: id='+cachel.id+' vi='+cachel.vi+
 200                         ' url='+cachel.url); */
 201                 return new Asset.image(this.vimgs[cachel.id][2][cachel.vi][2],{
 202                         id: this.vimgs[cachel.id][0],
 203                         title: this.vimgs[cachel.id][1],
 204                         onload: this.loadcomplete.bind(this,[cachel]),
 205                 });
 206         },
 207
 208         loadcomplete: function(cachel){
 209                 /* alert('loadcomplete '+cachel.url+' id='+cachel.id+
 210                         ' vi='+cachel.vi); */
 211                 cachel.ready = true;
 212                 if (cachel.id == this.currentid &&
 213                     this.pendingload) {
 214                         this.pendingload = false;
 215                         this.hideloading();
 216                         this.display(cachel);
 217                 }
 218         },
 219
 220         display: function(cachel){
 221                 var newstyle = this.calcsize(cachel);
 222                 var newimg = cachel.img.clone();
 223                 newimg.setStyles(newstyle);
 224                 newimg.setStyles({
 225                         zIndex: 3,
 226                         opacity: 0,
 227                 });
 228                 this.prevdisplay.dispose();
 229                 this.prevdisplay = this.ondisplay.clone().
 230                 setStyle('zIndex', 2).injectInside(this.container.container);
 231                 newimg.replaces(this.ondisplay);
 232                 this.ondisplay = newimg;
 233                 this.effect();
 234         },
 235
 236         effect: function(){
 237                 this.fx = new Fx.Tween(this.ondisplay, {
 238                         duration: this.options.fxduration,
 239                 });
 240                 this.fx.addEvent('complete',this.displaycomplete.bind(this));
 241                 this.fx.start('opacity', 0, 1);
 242         },
 243
 244         displaycomplete: function(){
 245                 this.prevdisplay.setStyle('display', 'none');
 246                 if (this.isplaying) {
 247                         this.timer = this.autonext.delay(this.delay,this);
 248                 }
 249         },
 250
 251         autonext: function(){
 252                 if (this.isplaying) {
 253                         if (this.currentid < this.vimgs.length-1) {
 254                                 this.show(this.currentid+1);
 255                         } else {
 256                                 this.exit();
 257                         }
 258                 }
 259         },
 260
 261         calcsize: function(cachel){
 262                 var factor = 1;
 263                 var candidate;
 264                 candidate = this.target.width /
 265                                 this.vimgs[cachel.id][2][cachel.vi][0];
 266                 if (factor > candidate) { factor = candidate; }
 267                 candidate = this.target.height /
 268                                 this.vimgs[cachel.id][2][cachel.vi][1];
 269                 if (factor > candidate) { factor = candidate; }
 270                 var w = Math.round(this.vimgs[cachel.id][2][cachel.vi][0] *
 271                         factor);
 272                 var h = Math.round(this.vimgs[cachel.id][2][cachel.vi][1] *
 273                         factor);
 274                 var t = Math.round((this.coords.height-h)/2);
 275                 var l = Math.round((this.coords.width-w)/2);
 276                 /* alert('new size: '+w+'x'+h+'+'+l+'+'+t); */
 277                 return {
 278                         position: 'absolute',
 279                         top: t+'px',
 280                         left: l+'px',
 281                         width: w,
 282                         height: h,
 283                 };
 284         },
 285
 286         showloading: function(){
 287                 this.loadingdiv.setStyle('display', 'block');
 288         },
 289
 290         hideloading: function(){
 291                 this.loadingdiv.setStyle('display', 'none');
 292         },
 293
 294         stopfx: function(){
 295                 if (this.fx) this.fx.cancel();
 296         },
 297
 298         updatecoords: function(){
 299                 this.coords = this.container.getCoordinates();
 300                 this.target = {
 301                         width: Math.round(this.coords.width *
 302                                                 this.options.percentage / 100),
 303                         height: Math.round(this.coords.height *
 304                                                 this.options.percentage / 100),
 305                 };
 306                 /* alert('coords: '+this.coords.width+'x'+this.coords.height+
 307                      ', target: '+this.target.width+'x'+this.target.height); */
 308         },
 309
 310 });
 311 Show.implement(new Options);
 312 Show.implement(new Events);
 313