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ReadPixelLine8 -- read the pen number value of a horizontal line
of pixels starting at a specified x,y location and continuing
right for count pixels. (V36)
count = ReadPixelLine8(rp,xstart,ystart,width,array,temprp)
D0 A0 D0:16 D1:16 D2 A2 A1
LONG ReadPixelLine8(struct RastPort *, UWORD, UWORD, UWORD,
UBYTE *, struct RastPort * );
For each pixel in a rectangular region, combine the bits from each
of the bit-planes used to describe a particular RastPort into the pen
number selector which that bit combination normally forms for the
system hardware selection of pixel color.
rp - pointer to a RastPort structure
(x,y) - a point in the RastPort
width - count of horizontal pixels to read
array - pointer to an array of UBYTEs from which to fetch the pixel data
allocate at least (((width+15)>>4)<<4) bytes.
temprp - temporary rastport (copy of rp with Layer set == NULL,
temporary memory allocated for
temprp->BitMap with Rows set == 1,
temprp->BytesPerRow == (((width+15)>>4)<<1),
and temporary memory allocated for
temprp->BitMap->Planes[])
For each pixel in the array:
Pen - (0..255) number at that position is returned
count - the number of pixels read.
width must be non negative
ReadPixel(), <graphics/rastport.h>
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