Does VE mess up PNG alpha for IE7?

Does VE mess up PNG alpha for IE7?

• Wilk06

  Can you could post a link that duplicates this alpha problem
  
  

• AbhijeetG

  IE7 supports alpha channel for PNGs, must be something in VE.

  Brian would be the man to know. Just need to get his attention

  http://www.spatialdatalogic.com/cs/blogs/brian_flood/

  I havn't played with PNG as yet for tiles (only jpg) due to the issues in IE6, interesting they may have resolved them only to break IE7.

  John.

  
  
  

• robinjam

  Great work Greg!

  Thanks for sharing that bug fix with us. Yes I also hope that this will be fixed with the next release of VE, I mean you've done all the hard work for them!

  I wouldn't be supprised though if it was implimented more generically to identify any IE versiongreater then or equal to 7. Hate for it to stop working in IE8 ;)

  John.

  
  
  

• Areej

  Thanks John. I'll try to get ahold of Brian if I can't figure it out. I've played some more (it's not what I'm supposed to be focused on this week ) and proved to myself that IE7 does handle the alphas just fine by z-indexing a hard coded instance of one of the tiles over top of the map, it looks fine. However, that beautifully rendered tile is sitting right beside the layer that mapcruncher is helping to render (same tileset!) in non-alpha'd mode. sigh.
  
  I fired a question off to microsoft research's mapcruncher team at the same time as this thread started, but no response yet. In the end I'm sure I'll be pouring over the obfusated JS of VE and/or mapcruncher to figure this out. It is probably one or the other doing a transform on the PNG.
  
  

• Damiaan

  I've got a work-around for my problem now.

  I had to tweak the VEAPI javascript so that when it's checking for filters it doesn't apply the alpha filter for IE7. That way IE7 falls through to the same method as other browsers (like firefox). If anyone else is interested, here's the location and hack I did (function G under Tile, the ['d] are supposed to be bracket d bracket but the thing changed them to ):

  if(b&&typeof b.filter!="undefined"&&navigator.userAgent.toLowerCase().indexOf("msie7")>-1){
  r=document.createElement("div");b=r.style;b.left=j['d];b.top=l['d];b.width=q['d];b.height=o['d];b.position="absolute";b.zIndex=h;
  b.filter="progid:DXImageTransform.Microsoft.AlphaImageLoader(src='"+a.src+"',sizingMethod='scale'), alpha(opacity="+m*100+")";
  map.appendChild(r)
  }
  else{
  b.zIndex=h;
  b.opacity=m;
  map.appendChild(a)
  }
  

  I sure hope the VE team fixes this soon! I tried using the link that grabs the latest JS (http://live.local.com/veapi.asjx) but it still has the problem. For now I'm using my hacked version and the boss is happy he can demo it (absolutely could NOT convince him to demo with firefox ), maybe it'll be fixed by the time we need to go live with it.

  Cheers,

  Greg

  
  

• Virgoss

  Good luck! If it comes to pouring over js send me an email and i may have something that can help you with that.

  John.

  
  
  

• gleason78

  Unfortunately I don't have a public link at the moment... I have been developing offline.
  I'll try to put something helpful up on a free service at some point shortly. If no one knows offhand, then it can't be a common problem. I'll play with the mapcruncher and VE JS files and see if maybe they are doing something...
  
  

• ChanKaiShi

  Glad to share. This is a great community. I started this project with almost no JS and no VE at all and I can muddle along quite well thanks to the VE forums, ViaVirtualEarth, the SDK, etc. It's great!
  
  Too right about the fix, though. My original hack was msie6 != -1 :) because I only care about ie6 and 7 -- figured when I posted it I would at least handle it such that anything other than ie7 fell into the trap... didn't consider newer!
  
  
• Does VE mess up PNG alpha for IE7?