(Karl said it's okay that I respond to this on-list)
On Sun, Apr 04, 2004 at 08:40:59PM +0200, Karl Ove Hufthammer wrote: > I noticed the *new* Tux Paint images in the gallery had non-white (light > grey) backgrounds, even though they weren't reduced to 256 colours. (This > isn't visible in 16-bit mode, but *very* visible in 32-bit mode. You can > check it in a graphics program if you can't run >16-bit.) Yes, thinking about it, I think I was wrong in suggesting that color reduction was the cause of the green tint on the screenshots. I realize now that (1) Tux Paint creates a 16bpp canvas, and (2) I've set all of my own displays to 16bpp, so I never saw a difference between the off-white color in the TP screenshots, and the 'true' white background color of the web page. :^) D'oh! > Then I tried creating new images in Tux Paint, and saving them. The images > had non-white backgrounds, so it looks like the colours are wrongly saved > *in* the images. This doesn't just happen with white. For example, the > lime colour has RGB values of 0,252,0 (should be 0,255,0), and blue has > 0,0,248. White has 248,252,248. > > I'm using the Windows version. Any idea what's causing this? Karl later pointed out an URL which I've somehow misplaced. It was an SDL mailing list post from circa 2000. I'm very groggy right now, so I can't remember if the proper solution would be to simply increase TP's canvas depth to 24bpp (to allow for true, 0xFFFFFF white) or to suggest waiting for an SDL upgrade. (Something about newer versions having improved scaling in 16bpp mode.) A hack could also be to interpret any 'almost white' colors in the SDL surface as 100% white when passing the pixels over to the PNG save library call. On a related note, I think the 16bpp'ness of the surfaces is the reason I sometimes see certain magical effects (say, "blur") starting to tint the picture green. -bill! [EMAIL PROTECTED] Have you visited the Linux Users' Group http://newbreedsoftware.com/bill/ of Davis yet!? http://www.lugod.org/ _______________________________________________ Tuxpaint-dev mailing list [EMAIL PROTECTED] http://tux4kids.net/mailman/listinfo/tuxpaint-dev
