> -----Original Message-----
> [mailto:[EMAIL PROTECTED] Behalf Of Melchior
> Sent: 11 January 2005 14:03
> To: flightgear-devel@flightgear.org
> Subject: [Flightgear-devel] fun with SGI images
> Erik reminded me to finish a program that I had written a 
> while ago. It uses
> the SGI Image loader/saver that I had written for KDE to 
> optimize image files,
> without changing the image contents. This is done by reducing 
> unused layers,
> using better compression, and not compressing where this 
> actually generates
> smaller images. I let this program now run over the 
> directories Textures{,.high}/
> and Aircraft/ and got this difference:
>   cvs:        223.61 MB
>   recoded:    182.09 MB
>   ----------------------
>   savings:     41.52 MB
> Now, what does it mean? That we should change all rgb(a), and 
> let every
> cvs users sync down 182 MB? Of course, not. But paying a little more
> attention to SGI images wouldn't hurt.
> m.

Do the texture files _have_ to be in RGB(A) format? 
I understand that lossy compression on textures is evil and wrong 
(http://www.sjbaker.org/steve/omniv/jpegs_are_evil_too.html), but what about 
PNG or even TIFF? These give smaller files with no information loss, and both 
support alpha layers properly.

Looking at the plib documentation, it says:

Currently, only SGI format and uncompressed 8 or 24 bit BMP images are 
supported - but more formats are planned for the future. Filenames ending with 
'.rgb', '.rgba', '.int', '.inta', '.bw' are assumed to be SGI formatted files, 
'.bmp' are in Microsoft's BMP format and '.png' are in Portable Network 
Graphics format. (http://plib.sourceforge.net/ssg/state.html)

Which first says that PNG is not supported, but then implies that it is. Does 
anyone know whether plib will load PNG files as textures?


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