Login
Username:

Password:

Remember me



Lost Password?

Register now!

Sections

Who's Online
126 user(s) are online (67 user(s) are browsing Forums)

Members: 1
Guests: 125

Firetail, more...

Headlines

 
  Register To Post  

Transparent PNG images
Supreme Council
Supreme Council


See User information
It seems as if PNG icons aren't rendered with the alpha channel intact. Is there any way to get IBrowse 2.4 to do that?

Vacca foeda. Sum, ergo edo

Mr Bobo Cornwater
Go to top
Re: Transparent PNG images
Not too shy to talk
Not too shy to talk


See User information
Quote:

orgin wrote:
It seems as if PNG icons aren't rendered with the alpha channel intact. Is there any way to get IBrowse 2.4 to do that?


That would seem to be possible using OS 4.0 Final, since MultiView renders PNG graphics with their alpha-channels.

Go to top
Re: Transparent PNG images
Just popping in
Just popping in


See User information
Quote:

orgin wrote:
It seems as if PNG icons aren't rendered with the alpha channel intact. Is there any way to get IBrowse 2.4 to do that?

It is working fine with a standard setup (OS4final + IBrowse 2.4 OEM).

Best regards,
hnl_dk - Henning Nielsen Lund [Denmark]
Go to top
Re: Transparent PNG images
Supreme Council
Supreme Council


See User information
@hnl_dk

Doesn't work here. The alpha channel is stripped.

See example here:

http://orgin.org/~orgin/icons/ibexample.png

Vacca foeda. Sum, ergo edo

Mr Bobo Cornwater
Go to top
Re: Transparent PNG images
Just can't stay away
Just can't stay away


See User information
@orgin

Doesn't work here either using the IBrowse OEM version (haven't changed any settings or such).

Works in AWeb though, and that's the browser I use.

Go to top
Re: Transparent PNG images
Just popping in
Just popping in


See User information
Ah, that'll be down to IBrowse.

IBrowse doesn't yet support full alpha channels. Basically, It takes the alpha channel at 50% & cuts it. i.e. The image shows up either solid, or transparent with no gradual alpha calculated in between.

AFAIK, there's no way around this until something gets updates with IBrowse. Changing the IB settings so that it uses an "external" image decoder for PNG's doesn't even sort it, even though we know the datatype supports alpha channels fully.

Sadly, for nice shaded/antialiased images on our web pages via IBrowse, we'll have to wait a bit.

FuZion.

Go to top
Re: Transparent PNG images
Just popping in
Just popping in


See User information
@FuZion

I'll have to check with Oliver again as I can never remember the correct answer to this one, but I believe its the lack of alpha blitting functions in the OS which is the cause of the problem. This was something I mentioned to Oliver a million times during 2.4's development cycle, and I think they added some alpha functions to OS4.0 right near the end so we never got the chance to alter IB to take advantage of them when running under OS4.

I'll check with Oliver again anyway :)

Go to top
Re: Transparent PNG images
Just popping in
Just popping in


See User information
@Vader

Cheers Vader. I don't know the technical side of what you guys go through but here's a link that may have some info too.

http://os4depot.net/index.php?functio ... lopment/library/ablit.lha

FuZion.

Go to top
Re: Transparent PNG images
Just popping in
Just popping in


See User information
@FuZion

Ok, spoke to Oliver IBrowse uses the graphics.library routines to draw the images, and those (at least for 68k programs) support only a 1-bit maskplane.

We will need to add support directly for the full 8-bit alpha channel of RGBA images.

The functions added to OS4.0 final to support 32-bit imagery were a) added right near the end which was too late for 2.4 as we were finalising more important issues (like crashes ) and b) were not sufficently documented at the time.

Hope that clears things up - and I will now go and add an FAQ

Go to top
Re: Transparent PNG images
Just popping in
Just popping in


See User information
@Vader

Cheers for the info guys. You catch that Origin

FuZion.

Go to top

  Register To Post

 




Currently Active Users Viewing This Thread: 1 ( 0 members and 1 Anonymous Users )




Powered by XOOPS 2.0 © 2001-2023 The XOOPS Project