2009-11-19 00:34:07 +00:00
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2012-01-05 22:45:03 +00:00
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loadpng: glue for Allegro and libpng
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2009-11-19 00:34:07 +00:00
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This wrapper is mostly a copy and paste job from example.c in the
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libpng docs, stripping out the useless transformations and making it
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use Allegro BITMAP and PALETTE structures. It is placed in the public
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domain.
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Requirements:
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2012-01-05 22:45:03 +00:00
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Allegro http://alleg.sourceforge.net/
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libpng http://www.libpng.org/pub/png/
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zlib http://www.gzip.org/zlib/
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2009-11-19 00:34:07 +00:00
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Usage:
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See loadpng.h for functions and their descriptions. There is a
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simple example program called example.c, a program demonstrating
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alpha translucency in exalpha.c, and a program demonstrating how to
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load a PNG object from a datafile in exdata.c.
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To compile, just run "make" (or perhaps "mingw32-make"). To use
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loadpng, you need to link with libpng, zlib in addition to loadpng
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itself, e.g.
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2012-01-05 22:45:03 +00:00
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gcc mygame.c -lldpng -lpng -lz -lalleg
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2009-11-19 00:34:07 +00:00
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I recommend you copy loadpng's files into your own project's directory
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and compile loadpng as part of your project.
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Notes:
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- Grayscale images will be loaded in as 24 bit images, or 32 bit
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images if they contain an alpha channel. These will then be
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converted as usual, according to Allegro's conversion semantics. Be
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aware of this if you have disabled automatic colour depth
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conversion.
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- save_png() doesn't save any gamma chunk. I'm thinking of making it
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write an sRGB chunk by default. If you want tight control of how
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your images are saved, I recommend hacking save_png() to suit your
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needs. There's simply too many options.
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Enjoy!
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Peter Wang (tjaden@users.sf.net)
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http://members.ozadsl.com.au/~tjaden/
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http://tjaden.strangesoft.net/
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