"

 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.

"

"{ Package: 'stx:libview' }"

GraphicsMedium subclass:#DisplaySurface

	instanceVariableNames:'viewBackground cursor eventMask middleButtonMenu keyCommands

		gotExpose backed flags delegate updateRegion'

	classVariableNames:''

	poolDictionaries:''

	category:'Graphics-Support'

!

DeviceHandle subclass:#DeviceViewHandle

	instanceVariableNames:''

	classVariableNames:''

	poolDictionaries:''

	privateIn:DisplaySurface

!

!DisplaySurface class methodsFor:'documentation'!

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.

"

!

documentation

"

    this abstract class describes stuff common to any Window on a display 

    device. i.e. RootWindow, TopWindows, PopUps and Subwindows.

    That is, they have a viewBackground, cursor etc. and especially events.

    A special feature is the delegate field, which allows key- and button 

    events to be stolen from a view. 

    If the delegate is non-nil, these events will be sent to it instead.

    So you can change a views behavior even if it was not initially designed 

    for it. Also, controller functionality could be simulated using delegates.

    [instance variables:]

	viewBackground  <Color|Form|Image>      the views background

	cursor          <Cursor>                the cursor

	eventMask                               mask specifying the enabled

						events.

	middleButtonMenu                        a popup menu for the middle

						button.

	keyCommands                             not yet supported

	gotExpose                               for exposure handling after

	exposePending                           after a scroll

	backed                                  one of #always, #whenMapped or #never

						corresponds to X's backing store

						mechanism.

						May be ignored by other devices.

	flags                                   flag bits

	    saveUnder                               bit 1; 1 if saveunder store for 

							     that view is enabled

	delegate                                for event delegation

    [see also:]

	DeviceWorkstation

	WindowGroup

	StandardSYstemView SimpleView View

    [author:]

	Claus Gittinger

"

! !

!DisplaySurface class methodsFor:'initialization'!

initialize

    SaveUnderFlagMask := 1.

! !

!DisplaySurface methodsFor:'accessing'!

depth

    "return the depth in pixels of the view.

     Notice, that this is currently the devices depth, 

     but support for mixed depth views is being prepared.

     (especially useful on SGI, with 24bit view)"

    ^ device depth

!

insideColor:aColor

    "set the views background color - ST-80 compatibility"

    self viewBackground:aColor.

    self background:aColor

!

keyboardMap

    "by default, use my devices standard mapping.

     However, subclasses may redefine this, to return their own

     keyboard map (for example a terminalView may want treat CTRL-C as regular key)"

    ^ device keyboardMap

!

setViewBackground

    "install the viewBackground for the receiver on the device"

    |id devBgPixmap bgPixmap w h colorMap 

     pixmapDepth deviceDepth defBG|

    drawableId notNil ifTrue:[

	viewBackground isColor ifTrue:[

	    viewBackground := viewBackground onDevice:device.

	    id := viewBackground colorId.

	    "

	     a real color (i.e. one supported by the device) ?

	    "

	    id notNil ifTrue:[

		device setWindowBackground:id in:drawableId.

		^ self

	    ].

	    "

	     no, a dithered one - must have a dither-pattern

	     (which is ready for the device, since viewBackground

	      is already assigned to the device)

	    "

	    bgPixmap := viewBackground ditherForm.

	] ifFalse:[

	    "

	     assume, it can convert itself to a form

	    "

	    bgPixmap := viewBackground asFormOn:device

	].

	"

	 must now have:

	 a dithered color or bitmap or pixmap

	"

	bgPixmap isNil ifTrue:[

	    'DisplaySurface [warning]: background not convertable - ignored' errorPrintCR.

	    ^ self

	].

	"/ if the device does not support background pixmaps,

	"/ set the backgroundColor to the default background.

	"/ this will avoid flicker in win32 systems,

	"/ since that background is drawn directly in the

	"/ devices expose event handling.

	"/ (in contrast, the pixmap filling is done by the

	"/ window itself in its expose event handler)

	(device supportsViewBackgroundPixmap:bgPixmap) ifFalse:[

	    defBG := View defaultViewBackgroundColor.

	    defBG isColor ifTrue:[

		defBG := defBG onDevice:device.

		id := defBG colorId.

		id notNil ifTrue:[

		    device setWindowBackground:id in:drawableId.

		].

	    ].

	    ^ self

	].

	w := bgPixmap width.

	h := bgPixmap height.

	deviceDepth := device depth.

	pixmapDepth := bgPixmap depth.

	(pixmapDepth ~~ deviceDepth) ifTrue:[

	    (pixmapDepth ~~ 1) ifTrue:[

		self error:'bad dither depth (must be one or devices depth)'.

		^ self

	    ].

	    "

	     convert it into a deep form

	    "

	    colorMap := bgPixmap colorMap.

	    devBgPixmap := Form width:w height:h depth:deviceDepth on:device.

	    devBgPixmap isNil ifTrue:[

		'DisplaySurface [warning]: could not create a device form for viewBackground' infoPrintCR.

		^ self

	    ].

	    devBgPixmap paint:(colorMap at:1).

	    devBgPixmap fillRectangleX:0 y:0 width:w height:h.

	    devBgPixmap foreground:(colorMap at:2) background:(colorMap at:1).

	    devBgPixmap copyPlaneFrom:bgPixmap x:0 y:0 toX:0 y:0 width:w height:h.

	    bgPixmap := devBgPixmap.

	] ifFalse:[

	    (pixmapDepth == 1) ifTrue:[

		"

		 although depth matches,

		 values in the dither are to be interpreted via the ditherForms

		 colormap, which is not always the same as blackpixel/whitepixel ...

		"

		colorMap := bgPixmap colorMap.

		(colorMap at:1) colorId == device whitepixel ifTrue:[

		    (colorMap at:2) colorId == device blackpixel ifTrue:[

			"

			 ok, can use it

			"

			device setWindowBackgroundPixmap:(bgPixmap id) in:drawableId.

			^ self

		    ]

		].

		"

		 no, must invert it

		"

		devBgPixmap := Form width:w height:h depth:deviceDepth on:device.

		devBgPixmap paint:(colorMap at:2) on:(colorMap at:1).

		devBgPixmap copyPlaneFrom:bgPixmap x:0 y:0 toX:0 y:0 width:w height:h.

		bgPixmap := devBgPixmap.

	    ]

	].

	device setWindowBackgroundPixmap:(bgPixmap id) in:drawableId.

    ]

    "Modified: / 4.5.1999 / 18:42:22 / cg"

!

viewBackground

    "return the viewBackground"

    ^ viewBackground

!

viewBackground:something

    "set the viewBackground to something, a color, image or form.

     The viewBackground is the color or pattern with which exposed

     regions are filled - do not confuse this with the drawing background

     color, which is used with opaque drawing."

    viewBackground ~~ something ifTrue:[

	viewBackground := something.

	drawableId notNil ifTrue:[

	    self setViewBackground

	]

    ]

!

viewBackgroundAndClear:something

    "set the viewBackground to something, a color, image or form.

     and clear the View.

     The viewBackground is the color or pattern with which exposed

     regions are filled - do not confuse this with the drawing background

     color, which is used with opaque drawing."

    self viewBackground:something.

    self clear.

    "Created: 27.4.1996 / 14:09:08 / cg"

!

viewGravity

    "return the views gravity"

    ^ #NorthWest

!

viewOrigin

    "0@0 here, since by default we cannot be scrolled"

    ^ 0 @ 0

!

widget

    "ST-80 compatibility"

    ^ self

! !

!DisplaySurface methodsFor:'accessing-cursor'!

cursor

    "return the views cursor"

    ^ cursor

!

cursor:aCursor

    "set the views cursor. This cursor will be automatically displayed whenever 

     the mouse-pointer enters the receiver. 

     Cursors are typically set at view creation time and left as installed."

    self cursor:aCursor now:true

    "

     |v|

     v := View new.

     v cursor:(Cursor wait).

     v open.

     [v shown] whileFalse:[Processor yield].

     [v shown] whileTrue:[   

	(Delay forSeconds:1) wait.

	v cursor:(Cursor normal).

	(Delay forSeconds:1) wait.

	v cursor:(Cursor wait).

     ]

    "

    "Modified: 14.12.1995 / 21:28:14 / cg"

!

cursor:aCursor now:showImmediately

    "set the views cursor. This cursor will be automatically displayed whenever 

     the mouse-pointer enters the receiver. 

     Cursors are typically set at view creation time and left as installed."

    aCursor notNil ifTrue:[

	(aCursor ~~ cursor) ifTrue:[

	    cursor := aCursor.

	    drawableId notNil ifTrue:[

		self setCursor.

		(showImmediately and:[realized]) ifTrue:[

		    "flush, to make cursor immediately visible"

		    device flush

		]

	    ]

	]

    ]

    "

     |v|

     v := View new.

     v cursor:(Cursor wait).

     v open.

     [v shown] whileFalse:[Processor yield].

     [v shown] whileTrue:[   

	(Delay forSeconds:1) wait.

	v cursor:(Cursor normal).

	(Delay forSeconds:1) wait.

	v cursor:(Cursor wait).

     ]

    "

    "Created: 14.12.1995 / 21:28:00 / cg"

    "Modified: 28.3.1997 / 13:47:58 / cg"

!

setCursor

    |id|

    drawableId notNil ifTrue:[

	cursor isNil ifTrue:[ ^ self].

	cursor := cursor onDevice:device.

	cursor isNil ifTrue:[ ^ self].

	id := cursor id.

	id isNil ifTrue:[

	    'DisplaySurface [warning]: nil cursorId ignored; shape=' errorPrint. 

	    cursor shape errorPrintCR.

	    ^ self.

	].

	device setCursor:id in:drawableId.

    ]

!

withCursor:aCursor do:aBlock

    "evaluate aBlock showing aCursor until ready; then restore the old cursor

     and return the value as returned by aBlock.

     Notice, that this method only changes the cursor for a SINGLE (sub-)view.

     Most applications want to have the cursor changed in all of its views.

     Use 'aView windowGroup withCursor:do:' or 'aView topView withCursor:do:'

     to acomplish this."

    |savedCursor|

    cursor == aCursor ifTrue:[

	^ aBlock value

    ].

    savedCursor := cursor.

    self cursor:aCursor.

    ^ aBlock valueNowOrOnUnwindDo:[self cursor:savedCursor]

    "Modified: 27.2.1997 / 17:20:43 / cg"

!

withExecuteCursorDo:aBlock

    "evaluate aBlock while showing an execute cursor in all my views.

     Return the value as returned by aBlock."

    ^ self withCursor:(Cursor execute) do:aBlock

    "Created: 10.1.1996 / 13:53:03 / cg"

!

withReadCursorDo:aBlock

    "evaluate aBlock while showing a readCursor in all my views.

     Return the value as returned by aBlock."

    ^ self withCursor:(Cursor read) do:aBlock

    "Modified: 14.12.1995 / 20:57:40 / cg"

    "Created: 10.1.1996 / 13:52:52 / cg"

!

withWaitCursorDo:aBlock

    "evaluate aBlock while showing a waitCursor in all my views.

     Return the value as returned by aBlock."

    ^ self withCursor:(Cursor wait) do:aBlock

    "Created: 10.1.1996 / 13:51:08 / cg"

! !

!DisplaySurface methodsFor:'accessing-hierarchy'!

delegate

    "return the delegate - thats the one getting keyboard and button events"

    ^ delegate

!

delegate:someOne

    "set the delegate - keyboard- and button events will be forwarded to

     that object if it is interested in them.

     See the sendEvent... method in WindowEvent."

    delegate := someOne

!

superView

    "return the superView - nil here"

    ^ nil

!

topComponent

    "return the topView - that the one with no superview"

    ^ self

    "Created: 9.5.1996 / 01:39:43 / cg"

!

topView

    "return the topView - that the one with no superview"

    ^ self

! !

!DisplaySurface methodsFor:'accessing-limits'!

maxExtent

    "return the views maximum extent - this is nil here.

     Only standardSystemViews support this."

    ^ nil

!

maxExtent:extent

    "set the views maximum extent - ignored here.

     Only standardSystemViews support this."

    ^ self

!

minExtent

    "return the views minimum extent - this is nil here.

     Only standardSystemViews support this."

    ^ nil

!

minExtent:extent

    "set the views minimum extent - ignored here.

     Only standardSystemViews support this."

    ^ self

! !

!DisplaySurface methodsFor:'accessing-misc'!

backingStore:how

    "turn on/off backingStore (saving my pixels)

     how may true/false, but also #always, #whenMapped or #never."

    how ~~ backed ifTrue:[

	backed := how.

	drawableId notNil ifTrue:[

	    device setBackingStore:how in:drawableId

	]