gpr_$read_pixels

GPR_$READ_PIXELS                  GPR Calls                   GPR_$READ_PIXELS


NAME
     gpr_$read_pixels - reads the pixel values from a window of the current
     bitmap.

FORMAT
     gpr_$read_pixels (source_window, pixel_array, status)

DESCRIPTION
     This routine reads the pixel values from a window of the current bitmap
     and stores the values in a pixel array.

     The pixel values from the source window of the current bitmap are stored
     in the pixel array in row-major order, one in each 4-byte integer.

   Input Parameters
     source_window
          Rectangular section of the current bitmap from which to read pixel
          values (color/intensity), in gpr_$window_t format.  This data type
          is 8 bytes long.

   Output Parameters
     pixel_array
          An array from which to read pixel values in gpr_$pixel_array_t for-
          mat.  This is an array of 4-byte integers.  You can specify an array
          of up to 131,073 elements.

     status
          Completion status, in status_$t format.

SEE ALSO
     gpr_$write_pixels.

NOTES
     To  write  pixel  values  from  an  array  to  the  current  bitmap,  use
     gpr_$write_pixels.

     A program cannot use this routine on a bitmap corresponding to a  Display
     Manager frame.

     A program cannot read pixel values in imaging formats.

     If you read more pixels than  there  are  in  pixel_array,  unpredictable
     results may occur.
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