'From Squeak3.9 of 7 November 2006 [latest update: #7067] on 17 October 2007 at 10:59:46 pm'!
"Change Set:		sketchPolygonUndo-nice
Date:			5 November 2007
Author:			Nicholas Cellier

Fixes a bug in use of undo in the painting tool when in polygon mode.

Gleaned from Mantis 6732, and vetted and harvested for olpc by Scott Wallace - sw 2/26/2008 14:48 "!

!SketchEditorMorph methodsFor: 'actions & preps' stamp: 'nice 10/17/2007 22:44'!
polyFreeze
	"A live polygon is on the painting.  Draw it into the painting and delete it."

	| poly |
	self polyEditing ifFalse:[^self].
	(poly _ self valueOfProperty: #polygon)
		ifNil:
			[self polyEditing: false.
			^ self].
	poly drawOn: formCanvas.
	poly delete.
	self setProperty: #polygon toValue: nil.
	self polyEditing: false.! !

!SketchEditorMorph methodsFor: 'start & finish' stamp: 'nice 10/17/2007 22:59'!
undo: evt 
	"revert to a previous state.  "

	| temp poly pen |
	self flag: #bob.	"what is undo in multihand environment?"
	undoBuffer ifNil: [^Beeper beep].	"nothing to go back to"
	(poly := self valueOfProperty: #polygon) ifNotNil: 
			[poly delete.
			self setProperty: #polygon toValue: nil.
			self polyEditing: false.
			^self].
	temp := paintingForm.
	paintingForm := undoBuffer.
	undoBuffer := temp.	"can get back to what you had by undoing again"
	pen := self get: #paintingFormPen for: evt.
	pen ifNil: [^Beeper  beep].
	pen setDestForm: paintingForm.
	formCanvas := paintingForm getCanvas.	"used for lines, ovals, etc."
	formCanvas := formCanvas copyOrigin: self topLeft negated
				clipRect: (0 @ 0 extent: bounds extent).
	self render: bounds! !