Martin Dressler wrote:
> I made some investigations in last days and find why my textures look
> so bad when scaled down to 128x128 textures compared to textures
> generated by perl scripts (writen by Andy?)
Uh, once upon a time, yeah. They're terrible hacks; not exactly my
best work. :)
> The problem isn't in scaling, because these scripts scale down too,
> but the diference is in how gimp render lines and ghostscript render
> lines.
No, it's the scaling. Ghostscript doesn't do antialiasing at all, it
just colors whole pixels. The scripts use gs to rasterize the image
at 4x (or even 16x, to get the whole 8 bit gray range) resolution and
then downsample to the target resolution using ImageMagick's mogrify
program.
> Is it posibble to change these scripts to produce dials with fully
> transparent background, or give them some texture to render on it.
The original scripts hack in alpha by using a chroma key. If you draw
anything in pure blue (I think), it'll come out transparent. This
actually exploits Ghostscript's inability to do sub-pixel rendering.
I think the alpha stuff was actually done with a tiny C program, but I
forget. :)
Alternatively, you can take the gray scale texture and use it as an
alpha channel underneath pure white (or black). That will get you the
effect you want. If gimp can't do this, you can write a really
trivial C program to turn the grayscale image into a raw RGBA file,
thence to a .png or whatnot using ImageMagick.
Andy
--
Andrew J. Ross Beyond the Ordinary Plausibility Productions
Sole Proprietor Beneath the Infinite Hillsboro, OR
Experience... the Plausible?
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