[SDL] importing an image with alpha from Paint Shop Pro
crusader at inwind.it
Fri May 9 06:23:01 PDT 2003
I've got an image created with paint shop pro that has some
semi-transparent pixels in it and I want to use it with my SDL application.
The first try I've made has been to set the background color to purple
(0xFF00FF), merge all layers and save it to PNG; then load the image with
SDL_image and set the colorkey to 0xFF00FF. This works for the pixel with
opacity 100% or 0%, but it doesnt't with semi-transparent ones (which are
blended with the background).
(1) Is there a file format both supported by psp7 and by some SDL library
that can store a RGBA surface?
(2) Is there some SDL library that can load a psp image into SDL surfaces?
(the PSP file format specs are public, but they''e 77 pages long...)
(3) are there any other alternatives?
I've thought about saving the image with two different backgrounds, i.e.
purple (0xFF00FF) and green (0x00FF00) and, by comparing the RGB pixels in
the two surfaces, revert to the original RGBA image. However, this is quite
a pain in the a** - and it's a bad, dirty work too.
 Guido Imperiale
crusaderky at libero.it
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