A TextContainer models the shape of an ownerMorph, possibly occluded by one or more occludingMorphs, and scans this shape to provide a list of rectangles suitable for layout of text. It does this by displaying the shadow of the ownerMorph in black, and any occludingMorphs in white, on its shadowForm. It then scans horizontal strips of appropriate height to find unbroken intervals of black, greater than minWidth in extent. Conputation of the rectangles is done on demand, and results are cached so that text can be redisplayed without having to recompute the rectangles.

	container protocol
	bottom left rectanglesAt:height: top topLeft translateBy: width

	private
	bounds computeShadow for:minWidth: shadowForm vertProfile

	access	top
	avoidsOcclusions
	avoidsOcclusions:
	fillsOwner
	fillsOwner:
	paragraphClass
	releaseCachedState
	textMorph

	container protocol	top
	bottom Note we should really check for contiguous pixels here
	left
	rectanglesAt:height: Return a list of rectangles that are at least minWidth wide in the specified horizontal strip of the shadowForm. Cache the results for later retrieval if the owner does not change.
	top Note we should really check for contiguous pixels here
	topLeft for compatibility
	translateBy:
	width for compatibility

	private	top
	bounds
	computeShadow
	for:minWidth:
	shadowForm
	vertProfile

	initialization	top
	initialize TextContainer initialize