Bounds calculation API is confusing

[tinchodias]

BlBounds comment states: "I am a mutable implementation of Rectangle which stores coordinates as Numbers and not Points. I am very useful for chainable bounds transformations and may be transformed in-place by BlMatrix2D and BlMatrix3D"

I add: There are plenty kinds of bounds that can be calculated on elements

• considering stroke outskirts (or not)
• considering children
• considering effects
• coordinates space: local, parent, space
• precise vs. just a fast estimation

No problem with that, it sounds good. The issue is about bounds-related API.

BUT:

Methods that calculate those BlBounds... there are cases that:

• modify an instance of BlBounds received as argument, and also return it
• return a new instance that can be updated
• return a new instance that is cached so must be copied before update
• use a BlBounds to make calculation but return it converted to Rectangle (and a sender bight re-convert it to BlBounds to calculate more)

Selectors, code and comment often don't explicit

Examples in BlElement:

effectBounds
	^ (self effectBounds: BlBounds new) asRectangle

boundsInSpace: aBounds
	"I load my bounds in space in a given mutable rectangle and return provided one.
	I do not rely on cache and always provide actual bounds.
	I am a part of internal api, use me with caution"

	self boundsInLocal: aBounds.
	self localBoundsToGlobal: aBounds.
	^ aBounds

invalidationBounds: aBounds
	"Compute the bounds of self, including my children recursively, in my local
	coordinates that would be invalidated if #invalidate would be sent to me."

	| anInvalidationBounds |
	anInvalidationBounds := (self effectBounds: aBounds) merge: self boundsInLocal.

	(self clipChildren and: [ self hasChildren ]) ifFalse: [ 
		| aChildBounds |
		aChildBounds := BlBounds new.
		self children do: [ :anElement |
			anElement invalidationBounds: aChildBounds.
			anElement localBoundsToParent: aChildBounds.
			anInvalidationBounds merge: aChildBounds ] ].

	^ anInvalidationBounds

[tinchodias]

Ideas:

• effectBounds either don't convert to Rectangle, or call it effectRectangle
• boundsInSpace:may be addBoundsInSpaceInto: or alternative prefixes: load or compute; alternative suffix: On:like in printOn:
• localBoundsToParent: could be transformBoundsToParent:

@plantec @labordep ?

[plantec]

I agree, I find these names confusing too. And we should avoid Rectangle computation as much as possible