Class: XBMReader

• Inheritance
• Description
• Class protocol
  • class initialization
  • testing
• Instance protocol
  • private-reading
  • reading
  • writing
• Examples

Inheritance:

   Object
   |
   +--ImageReader
      |
      +--XBMReader

Package:

stx:libview2

Category:

Graphics-Images-Readers

Version:

rev: 1.67 date: 2023/10/12 16:16:38

user: stefan

file: XBMReader.st directory: libview2

module: stx stc-classLibrary: libview2

Description:

this class provides methods for loading and saving x-bitmap-file images.
These images can (for example) be created using the bitmap editor supplied
with X. 
Only monochrome images can be represented in this format.
Both reading and writing of images is supported.

copyright
COPYRIGHT (c) 1992 by Claus Gittinger
             All Rights Reserved

This software is furnished under a license and may be used
only in accordance with the terms of that license and with the
inclusion of the above copyright notice.   This software may not
be provided or otherwise made available to, or used by, any
other person.  No title to or ownership of the software is
hereby transferred.

Class protocol:

 initialize

tell Image-class, that a new fileReader is present
for the '.xbm' extension.

 canRepresent: anImage

return true, if anImage can be represented in my file format

 isValidImageStream: inStream

return true, if inStream possibly contains a XBM image.
The stream is left open and position undefined afterwards

Instance protocol:

 extractValueFor: keyword fromLine: lineString

 fromStream: aStream

read an image in xbm format from aStream.
Leave image description in instance variables.
(i.e. to get the image, ask with image).

 save: image onStream: aStream

save image as XBM cdata on aStream.
Only depth1 b&w images can be represented in this format.

Usage example(s):

|file original restored| original := Image fromFile:'../../goodies/bitmaps/xbmBitmaps/TicTacToe.xbm'. file := String streamContents:[:stream | XBMReader save:original onStream:stream ]. restored := XBMReader fromStream:(file readStream). self assert:(restored = original)

Examples:

  |image|

  image := Image fromFile:('../../goodies/bitmaps/xbmBitmaps/TicTacToe.xbm').
  image inspect

  |image|

  image := Image fromScreen:(0@0 corner:30@30).
  image := image asThresholdMonochromeImage.
  XBMReader save:image onFile:'/tmp/test.xbm'.
  '/tmp/test.xbm' asFilename contents asString inspect.
  (Image fromFile:('/tmp/test.xbm')) inspect.

  |image stream|

  image := Image fromScreen:(0@0 corner:30@30).
  image := image asThresholdMonochromeImage.
  stream := WriteStream on:(String new).
  XPMReader save:image onStream:stream.
  stream contents inspect.