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(aalib.info)Drawing image

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How to draw an image?
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   AA-lib emulates video-ram so it looks just like a plain memory. It
contains `aa_imgheight (context)' lines of `aa_imgwidth(context)' bytes
where each of them specifies a grayscale value or an index to a colormap
(or graymap ?).  Pointer to this memory can be obtained using
`aa_image(context)' macro.

   Note that width and height of videoram differ from physical
width/height of a device (stored in `aa_hardwareparams' variables).
Currently it is twice bigger because every four pixels are rendered
into one character.  Future versions should (possibly) support nine
pixels.

   There's nearly no difference in API between classical gfx libraries
and AA-lib.  There are currently no higher level graphics functions.
But AA-lib provides `aa_putpixel(context,x,y,color)' macro. There is no
problem to make more complex functions. A great help to a potential
programmer is the fact that AA-lib provides a colormap mode emulation.
To set the palette you should use macro:

     aa_setpalette(PALETTE, INDEX, RED, GREEN, BLUE)

   Red, green and blue components are recalculated into super-grayscale.
Values are in range 0-255 where 0 means black. You can also set
directly value using something like:

     palette[index]=value;

   Another difference is that your aplication is expected to handle
various imgwidth/imgheights (in case you didn't exacly specified them in
hardwareparams during initialization). Also your aplication should take
care for `aa_mmwidth(context)' and `aa_mmheight(context)' values that
contain real size in millimeters of output device. You cannot simply
expect that pixel has the same width and height as at normal graphics
libraries.

   Many old programs may require some scalling functions to convert
images from their internal size (320x200) to AA-Lib real size.

   Note that image WON'T be displayed on the screen unless it is
rendered and FLUSHED !