Unit 'agraphics' Package
[Overview][Constants][Types][Procedures and functions][Variables][Index] [#os4units]

ReadPixelArray8

read the pen number value of a rectangular array of pixels starting at a specified x,y location and continuing through to another x,y location within a certain RastPort.

Declaration

Source position: agraphics.pas line 2424

function ReadPixelArray8(

  Rp: PRastPort;

  XStart: LongWord;

  YStart: LongWord;

  XStop: LongWord;

  YStop: LongWord;

  Array_: PByte;

  TempRP: PRastPort

):LongInt;

Arguments

Rp

  

A pointer to a RastPort

XStart

  

X starting point

YStart

  

Y starting point

XStop

  

X stop point

YStop

  

Y stop point

Array_

  

A Pointer to an array of Bytes from which to fetch the pixel data allocate at least ((((width + 15) shr 4) shl 4) * (ystop - ystart + 1)) bytes.

TempRP

  

A temporary rastport (copy of rp with Layer set = nil, temporary memory allocated for temprp^.BitMap with Rows set == 1, temprp^.BytesPerRow = (((width + 15) shr 4) shl 1), and temporary memory allocated for temprp^.BitMap^.Planes[])

Function result

The number of pixels read.

Description

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.

xstop must be >= xstart; ystop must be >= ystart

This function doesn't make sense on true-/hicolor rastports.

See also

ReadPixel

  

read the pen number value of the pixel at a specified x,y location within a certain RastPort.

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.

WritePixelArray8

  

Write the pen number value of a rectangular array of pixels starting at a specified x,y location and continuing through to another x,y location within a certain RastPort.

WritePixelLine8

  

Write the pen number value of a horizontal line of pixels starting at a specified x,y location and continuing right for count pixels.


Documentation generated on: 2021-07-30