"

 COPYRIGHT (c) 1994 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.

"

'From Smalltalk/X, Version:2.10.4 on 18-feb-1995 at 2:24:00 am'!

ImageReader subclass:#XPMReader

	 instanceVariableNames:''

	 classVariableNames:''

	 poolDictionaries:''

	 category:'Graphics-Images support'

!

!XPMReader class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1994 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.

"

!

version

"

"

!

documentation

"

    this class provides methods for loading x-pixmap-file (xpm) images.

    These images are used (in X) for palette images (see ctwm or hp-vue for a lot

    of them). The code here is a hack - it may not work for all images (it works

    for the testfiles I got here).

    Limitations: 

	only reads the full-color specification, ignoring monochrome

	and greyscale info.

	Can only handle single-character index.

	Does not (currently) handle none-colors (i.e. for image-masks).

	Save not supported

    Suggestions: adapt & use the XPM library here.

"

! !

!XPMReader class methodsFor:'initialization'!

initialize

    Image fileFormats at:'.xpm'  put:self.

! !

!XPMReader class methodsFor:'testing'!

isValidImageFile:aFileName

    "return true, if aFileName contains an x-bitmap-file image"

    |line inStream |

    inStream := self streamReadingFile:aFileName.

    inStream isNil ifTrue:[^ false].

    line := inStream nextLine.

    inStream close.

    line isNil ifTrue:[^ false].

    (line startsWith:'/* XPM') ifFalse:[^ false].

    ^ true

    "

     XPMReader isValidImageFile:'bitmaps/magtape.xpm'    

     XPMReader isValidImageFile:'bitmaps/ljet.xpm'      

     XPMReader isValidImageFile:'bitmaps/garfield.gif' 

    " 

! !

!XPMReader methodsFor:'reading from file'!

colorNameFrom:aStream

    "read either a color-name or value specified in X-notation

     (#rrggbb where rr, gg and bb are 2-digit hex numbers)"

    |s|

    aStream peek == $# ifTrue:[

	aStream next.

	s := '#'.

    ] ifFalse:[

	s := ''.

    ].

    [aStream peek isLetterOrDigit] whileTrue:[

	s := s copyWith:aStream next

    ].

    ^ s

!

fromStream:aStream

    "read an XPM-image from aStream. Return the receiver 

     (with all relevant instance variables set for the image) 

     or nil on error"

    |line 

     srcIndex "{ Class: SmallInteger }"

     dstIndex "{ Class: SmallInteger }"

     colorName colorMapSize redMap greenMap blueMap

     charsPerPixel xlation s bitsPerPixel char lineDone|

    inStream := aStream.

    line := aStream nextLine.

    (line notNil and:[line startsWith:'/* XPM']) ifFalse:[

	'XPM: format error (expected XPM)' errorPrintNL.

	^ nil

    ].

    line := aStream nextLine.

	line := aStream nextLine.

    ].

    (line notNil and:[line startsWith:'static char']) ifFalse:[

	'XPM: format error (expected static char)' errorPrintNL.

	^ nil

    ].

    line := aStream nextLine.

    ].

    (line notNil and:[line startsWith:'"']) ifFalse:[

	'XPM: format error (expected "ww hh nn mm)' errorPrintNL.

	^ nil

    ].

    s := ReadStream on:line.

    s next.  "skip quote"

    width := Integer readFrom:s.

    height := Integer readFrom:s.

    colorMapSize := Integer readFrom:s.

    charsPerPixel := Integer readFrom:s.

    charsPerPixel ~~ 1 ifTrue:[

	'XPM: can only handle single-character xpm-files' errorPrintNL.

	^ nil

    ].

    xlation := Array new:256.

    colorMap := Colormap redVector:redMap greenVector:greenMap blueVector:blueMap.

    1 to:colorMapSize do:[:colorIndex |

	line := aStream nextLine.

	[line notNil and:[line startsWith:'/*']] whileTrue:[

	    line := aStream nextLine.

	].

	(line notNil and:[line startsWith:'"']) ifFalse:[

	    'XPM: format error (expected color spec)' errorPrintNL.

	    ^ nil

	].

	s := ReadStream on:line.

	s next. "skip quote"

	index := s next asciiValue.

	xlation at:index put:colorIndex - 1.

	lineDone := false.

	[lineDone] whileFalse:[

	    s skipSeparators.

	    char := s peek.

	    char == $" ifTrue:[

		lineDone := true

	    ] ifFalse:[

		char == $s ifTrue:[

		    "

		     symbolic name

		    "

		    s next.

		    s skipSeparators.

		    self colorNameFrom:s.  

		    s skipSeparators.

		] ifFalse:[

		    char == $m ifTrue:[

			"

			 monochrome data

			"

			s next.

			s skipSeparators.

			self colorNameFrom:s.

			s skipSeparators.

		    ] ifFalse:[

			(char == $g) ifTrue:[

			    "

			     greyscale data

			    "

			    s next.

			    s peek == 4 ifTrue:[s next].

			    s skipSeparators.

			    self colorNameFrom:s.

			    s skipSeparators.

			] ifFalse:[

			    (char == $c) ifTrue:[

				"

				 color data

				"

				s next.

				s skipSeparators.

				colorName := self colorNameFrom:s.

				s skipSeparators.

			    ] ifFalse:[

				'XPM: format error got: ' errorPrint.

"/                                char errorPrint. '(' errorPrint. char asciiValue printString errorPrint.

"/                                '); ' errorPrint.

				 '(expected ''c'',''m'',''g'' or ''s'')' errorPrintNL.

				^ nil

			    ].

			]

		    ]

		]

	    ].

	].

	((colorName = 'none') or:[colorName = 'None']) ifTrue:[

	    "mhmh must add mask to Image-instances soon ..."

	    color := Color white

	] ifFalse:[

	    color := Color name:colorName.

	].

    ].

    "actually, could make it an image with less depth most of the time ..."

"

    bitsPerPixel := ((colorMapSize - 1) log:2) truncated + 1.

"

    bitsPerPixel := 8.

    data := ByteArray new:(width * height).

    dstIndex := 1.

    1 to:height do:[:row |

	line := aStream nextLine withoutSpaces.

	[line notNil and:[line startsWith:'/*']] whileTrue:[

	    line := aStream nextLine withoutSpaces.

	].

	(line notNil and:[line startsWith:'"']) ifFalse:[

	    'XPM: format error (expected pixels)' errorPrintNL.

	    ^ nil

	].

	srcIndex := 2.

	1 to: width do:[:col |

	    |char|

	    char := line at:srcIndex.

	    data at:dstIndex put:(xlation at:char asciiValue).

	    srcIndex := srcIndex + 1.

	    dstIndex := dstIndex + 1

	]

    ].

    photometric := #palette.

    samplesPerPixel := 1.

    bitsPerSample := Array with:bitsPerPixel.

    "

     XPMReader fromStream:('bitmaps/ljet.xpm' asFilename readStream)

     XPMReader fromStream:('bitmaps/magtape.xpm' asFilename readStream)

     XPMReader fromStream:('bitmaps/pixmap.xpm' asFilename readStream) 

     XPMReader fromStream:('bitmaps/SBrowser.xbm' asFilename readStream)

! !

XPMReader initialize!