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

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.

Declaration

Source position: agraphics.pas line 2422

function ReadPixelLine8(

  Rp: PRastPort;

  XStart: LongWord;

  YStart: LongWord;

  Width: LongWord;

  Array_: PByte;

  TempRP: PRastPort

):LongInt;

Arguments

Rp

  

A pointer to a RastPort

XStart

  

X Postion in Line to start to read

YStart

  

Line to Read

Width

  

Length of line to read

Array_

  

Pointer to an array of Bytes from which to fetch the pixel data allocate at least (((width + 15) shr 4) shl 4) 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.

width must be non negative

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.

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.

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