"

 COPYRIGHT (c) 1989 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.

"

GraphicsMedium subclass:#Form

	instanceVariableNames:'depth localColorMap offset data fileName'

	classVariableNames:'VeryLightGreyForm LightGreyForm GreyForm DarkGreyForm

		VeryDarkGreyForm AdditionalBitmapDirectoryNames

		BlackAndWhiteColorMap DitherPatternArray'

	poolDictionaries:''

	category:'Graphics-Display Objects'

!

!Form  class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1989 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.

"

!

documentation

"

    Instances of this class represent forms (i.e. bit- and pixmaps)

    which can be created on a drawing device. 

    In X, these device resources are XPixmaps.

    Not all devices will support forms.

    NOTICE:

        the Form class is a historic leftover and now only used for real

        device forms (i.e. on devices which support downloading bitmaps).

        In your application, you should always use Image, both for compatibility

        with ST-80 and for device independence, since Form may not be supported

        by all devices.

    WARNING:

        Forms created on some device may not be recreatable, when an

        image is restarted on a display with different display capabilities.

        For example, a 24bit truecolor form will be lost when the image is

        saved and restarted in an 8bit or monochrome display.

        Worse: the information is completely lost.

        With images, the original information is always preserved, although

        the display may be with less resolution, dithered or otherwise

        approximated.

    [See also:]

        Image DeviceDrawable

    [author:]

        Claus Gittinger

"

! !

!Form  class methodsFor:'initialization'!

flushDeviceForms

    "recreate all forms on aDevice; called by Workstation, to

     have all background bitmaps at hand, when views are restored"

    Lobby do:[:aDrawable |

        aDrawable isForm ifTrue:[

            (aDrawable graphicsDevice notNil) ifTrue:[

                "now, try to recreate it"

                aDrawable recreate.

            ]

        ]

    ]

    "Created: 18.6.1996 / 13:04:59 / cg"

    "Modified: 5.7.1996 / 17:56:02 / cg"

!

initialize

    "initialize set of dictionaries to look for bitmaps"

    AdditionalBitmapDirectoryNames isNil ifTrue:[

	AdditionalBitmapDirectoryNames := #('/usr/lib/X11/bitmaps').

	"want to be informed when returning from snapshot"

	ObjectMemory addDependent:self.

    ]

!

reinitializeAllOn:aDevice

    "recreate all forms on aDevice; called by Workstation, to

     have all background bitmaps at hand, when views are restored"

    Lobby do:[:aDrawable |

        (aDrawable graphicsDevice == aDevice) ifTrue:[

            aDrawable isForm ifTrue:[

                "now, try to recreate it"

                aDrawable recreate.

            ]

        ]

    ]

    "Modified: 5.7.1996 / 17:55:58 / cg"

!

update:something with:aParameter from:changedObject

    "sent just before snapOut and just after a snapIn"

    (something == #save) ifTrue:[

        "get all bits from the device into saveable arrays"

        Lobby do:[:aDrawable |

            aDrawable isForm ifTrue:[

                aDrawable getBits

            ]

        ]

    ].

    (something == #restarted) ifTrue:[

        "remove all left-over device info"

        Lobby do:[:aDrawable |

            aDrawable isForm ifTrue:[

                aDrawable flushDeviceHandles.

                Lobby registerChange:aDrawable 

            ]

        ]

    ]

    "Modified: 15.6.1996 / 15:44:09 / cg"

    "Created: 15.6.1996 / 15:47:50 / cg"

! !

!Form  class methodsFor:'instance creation'!

extent:ext

    "create a new, cleared form, take dimensions from ext.

     Smalltalk-80 compatibility"

    |newForm|

    newForm := self width:(ext x) height:(ext y).

    newForm fill:(Color colorId:0).

    newForm paint:(Color colorId:1).

    ^ newForm

!

extent:ext fromArray:data

    "create a new form, take dimensions from ext, bits from data.

     Smalltalk-80 compatibility."

    ^ self width:(ext x) height:(ext y) offset:0@0 fromArray:data

!

extent:ext fromArray:data offset:offs

    "create a new form, take dimensions from ext, bits from data.

     Smalltalk-80 compatibility."

    ^ self width:(ext x) height:(ext y) offset:offs fromArray:data

!

extent:ext offset:anOffset

    "create a new, cleared form, take dimensions from ext.

     Smalltalk-80 compatibility"

    ^ (self extent:ext) offset:anOffset.

!

width:w height:h

    "create a new form on the default device"

    ^ self width:w height:h on:Screen current

    "Modified: 4.6.1996 / 22:16:33 / cg"

!

width:w height:h depth:d

    "create a new form on the default device"

    ^ self width:w height:h depth:d on:Screen current

    "Modified: 4.6.1996 / 22:16:51 / cg"

!

width:w height:h depth:d on:aDevice

    "create a new form with depth d on device, aDevice"

    ^ (self on:aDevice) width:w height:h depth:d

!

width:w height:h fromArray:anArray

    "create a new form on the default device"

    ^ self width:w height:h fromArray:anArray on:Screen current

    "Modified: 4.6.1996 / 22:17:05 / cg"

!

width:w height:h fromArray:anArray on:aDevice

    "create a new form on device, aDevice and

     initialize the pixels from anArray"

    ^ (self on:aDevice) width:w height:h fromArray:anArray

!

width:w height:h offset:offs fromArray:anArray

    "create a new form on the default device"

    ^ (self on:Screen current) width:w height:h offset:offs fromArray:anArray

!

width:w height:h on:aDevice

    "create a new form on device, aDevice; depth is what device likes most"

    ^ (self on:aDevice) width:w height:h

! !

!Form  class methodsFor:'ST-80 compatibility'!

and

    "return a constant usable as bitblt-combinationrule.

     In ST-80rel2.x, these used to be numeric constants; in ST/X,

     these are symbolic."

    ^ #and

    "Modified: 2.5.1996 / 11:41:23 / cg"

!

black

    "ST80 compatibility;

     In old st80, you could use `Form black' for drawing 

     - here we return the black color."

    ^ Color black

    "Modified: 2.5.1996 / 11:44:17 / cg"

!

darkGray

    "ST80 compatibility;

     In old st80, you could use `Form darkGray' for drawing 

     - here we return the darkGray color."

    ^ Color darkGray

    "Modified: 2.5.1996 / 11:44:06 / cg"

!

darkGrey

    "ST80 compatibility;

     In old st80, you could use `Form darkGrey' for drawing 

     - here we return the darkGrey color."

    ^ Color darkGray

    "Modified: 28.5.1996 / 20:47:54 / cg"

!

gray

    "ST80 compatibility;

     In old st80, you could use `Form gray' for drawing 

     - here we return the grey color."

    ^ Color gray

    "Modified: 2.5.1996 / 11:43:44 / cg"

!

grey

    "ST80 compatibility;

     In old st80, you could use `Form grey' for drawing 

     - here we return the grey color."

    ^ Color grey

    "Modified: 2.5.1996 / 11:43:17 / cg"

!

lightGray

    "ST80 compatibility;

     In old st80, you could use `Form lightGray' for drawing 

     - here we return the lightGray color."

    ^ Color lightGray

    "Created: 2.5.1996 / 11:40:07 / cg"

    "Modified: 2.5.1996 / 11:43:21 / cg"

!

lightGrey

    "ST80 compatibility;

     In old st80, you could use `Form lightGray' for drawing 

     - here we return the lightGray color."

    ^ Color lightGray

    "Modified: 28.5.1996 / 20:53:28 / cg"

!

over

    "return a constant usable as bitblt-combinationrule.

     In ST-80rel2.x, these used to be numeric constants; in ST/X,

     these are symbolic."

    ^ #copy

    "Modified: 2.5.1996 / 11:41:31 / cg"

!

paint

    "return a constant usable as bitblt-combinationrule.

     In ST-80rel2.x, these used to be numeric constants; in ST/X,

     these are symbolic."

    ^ #copy

    "Modified: 2.5.1996 / 11:41:40 / cg"

!

reverse

    "return a constant usable as bitblt-combinationrule.

     In ST-80rel2.x, these used to be numeric constants; in ST/X,

     these are symbolic."

    ^ #xor

    "Modified: 2.5.1996 / 11:41:45 / cg"

!

under

    "return a constant usable as bitblt-combinationrule.

     In ST-80rel2.x, these used to be numeric constants; in ST/X,

     these are symbolic."

    ^ #or

    "Modified: 2.5.1996 / 11:41:49 / cg"

!

white

    "ST80rel2.x compatibility;

     In old st80, you could use `Form white' for drawing 

     - here we return the white color."

    ^ Color white

    "Modified: 2.5.1996 / 11:42:50 / cg"

! !

!Form  class methodsFor:'cleanup'!

lowSpaceCleanup

    "cleanup in low-memory situations"

    DitherPatternArray := nil

! !

!Form  class methodsFor:'file search'!

findBitmapFile:fileName

    "find the bitmap file in one of the standard places;

     return the pathName or nil"

    |aStream path|

    ((fileName at:1) == $/) ifTrue:[^ fileName].

    (fileName startsWith:'../') ifTrue:[^ fileName].

    (fileName startsWith:'./') ifTrue:[^ fileName].

    fileName asFilename exists ifTrue:[^ fileName].

    aStream := Smalltalk bitmapFileStreamFor:fileName.

    aStream notNil ifTrue:[

	path := aStream pathName.

	aStream close.

	^ path

    ].

    AdditionalBitmapDirectoryNames notNil ifTrue:[

	AdditionalBitmapDirectoryNames do:[:aPath |

	    path := aPath , '/' , fileName.

	    (OperatingSystem isReadable:path) ifTrue:[

		^ path

	    ]

	]

    ].

    ^ nil

! !

!Form  class methodsFor:'fileIn/Out'!

fromFile:filename

    "create a new form taking the bits from a file on the default device.

     WARNING:

     Please do no longer use this, since it will not work

     correctly in multi-display applications (creates the form on the

     default Display).

     Use #fromFile:on: and pass the devive as argument."

    ^ self fromFile:filename on:Screen current

!

fromFile:filename on:aDevice

    "create a new form on device, aDevice and

     initialize the pixels from the file filename"

    ^ (self on:aDevice) readFromFile:filename

!

fromFile:filename resolution:dpi

    "create a new form taking the bits from a file on the default device

     the data in the file is assumed to be for dpi resolution;

     if it is different from the displays resolution, magnify or

     shrink the picture (but only in integer magnification steps).

     WARNING:

     Please do no longer use this, since it will not work

     correctly in multi-display applications (creates the form on the

     default Display).

     Use #fromFile:resolution:on: and pass the devive as argument."

    ^ self fromFile:filename resolution:dpi on:Screen current

!

fromFile:filename resolution:dpi on:aDevice

    "create a new form on device, aDevice and

     initialize the pixels from the file filename;

     the data in the file is assumed to be for dpi resolution;

     if it is different from the displays resolution, magnify or

     shrink the picture (but only in integer magnification steps)"

    ^ (self on:aDevice) readFromFile:filename resolution:dpi

!

readFrom:fileName

    "same as Form>>fromFile: - for ST-80 compatibility.

     WARNING:

     Please do no longer use this, since it will not work

     correctly in multi-display applications (creates the form on the

     default Display).

     Use #fromFile:on: and pass the devive as argument."

    ^ self fromFile:fileName on:Screen current

! !

!Form  class methodsFor:'obsolete instance creation'!

darkGreyFormOn:aDevice

    "return a darkGrey form"

    |f|

    ((aDevice == Display) and:[DarkGreyForm notNil]) ifTrue:[

	^ DarkGreyForm

    ].

    f := self width:8 height:4 fromArray:(self darkGreyFormBits) on:aDevice.

    (aDevice == Display) ifTrue:[

	DarkGreyForm := f

    ].

    ^ f

!

grey:percent on:aDevice

    "return a form for dithering"

    (percent < 20) ifTrue:[^ Color black on:aDevice].

    (percent < 40) ifTrue:[^ self darkGreyFormOn:aDevice].

    (percent < 60) ifTrue:[^ self mediumGreyFormOn:aDevice].

    (percent < 80) ifTrue:[^ self lightGreyFormOn:aDevice].

    ^ Color white on:aDevice

!

lightGreyFormOn:aDevice

    "return a lightGrey form"

    |f|

    ((aDevice == Display) and:[LightGreyForm notNil]) ifTrue:[

	^ LightGreyForm

    ].

    f := self width:8 height:4 fromArray:(self lightGreyFormBits) on:aDevice.

    (aDevice == Display) ifTrue:[

	LightGreyForm := f