I moved this to trunk, and moved the earlier Graphics submission to
treated inbox.

Followup needed - MorphicExtras-kfr.254 and other MorphicExtras still
in the inbox need to be reviewed and merged.

Dave


On Fri, Mar 22, 2019 at 01:18:55PM +0000, commits at source.squeak.org wrote:
> David T. Lewis uploaded a new version of MorphicExtras to project The Trunk:
> http://source.squeak.org/trunk/MorphicExtras-ms.254.mcz
> 
> ==================== Summary ====================
> 
> Name: MorphicExtras-ms.254
> Author: ms
> Time: 22 March 2019, 1:48:31.043664 pm
> UUID: d7b3adea-c5be-47f1-8247-7c5ae1ad7f34
> Ancestors: MorphicExtras-kfr.253
> 
> Adds a preview morph for results of all BitBlt rules. 
> 
> When first using BitBlt, it wasn't easy to understand the effects of the possible rules on pixel combinating for me. 
> I implemented two example methods which preview the effects of rule 0 to 41 (these are all, I believe) on quadratic existing forms with colors and 1 bit alpha channel (previewAllBitBltRules uses ToolIcons flag/collection) plus Forms with more alpha values (previewAllBitBltRulesWithAlpha uses ToolIcons flag and a Color red + 0.4 alpha preview). They generate a combined morph for all rules applied on these forms (scaled, because icons are small) and opens it in your hand. 
> Internally, this morph can be generated for any rule, forms and scale. Rules which throw exceptions are replaced with a fallback form. 
> 
> Now in the correct package (see http://forum.world.st/The-Inbox-Graphics-ms-407-mcz-td5097206.html ).
> Thank you for your feedback!
> 
> =============== Diff against MorphicExtras-kfr.253 ===============
> 
> Item was added:
> + ----- Method: BitBlt class>>previewAllBitBltRules (in category '*MorphicExtras') -----
> + previewAllBitBltRules
> + 
> + 	(self previewBitBltRules: (0 to: 41)
> + 		on: ToolIcons flag
> + 		and: ToolIcons collection
> + 		fallback: ToolIcons exception
> + 		scaledTo: 32) openInHand.!
> 
> Item was added:
> + ----- Method: BitBlt class>>previewAllBitBltRulesWithAlpha (in category '*MorphicExtras') -----
> + previewAllBitBltRulesWithAlpha
> + 
> + 	(self previewBitBltRules: (0 to: 41)
> + 		on: ToolIcons flag
> + 		and: ((Color red alpha: 0.4) iconOrThumbnailOfSize: 12)
> + 		fallback: ToolIcons exception
> + 		scaledTo: 32) openInHand.!
> 
> Item was added:
> + ----- Method: BitBlt class>>previewBitBltRules:on:and:fallback:scaledTo: (in category '*MorphicExtras') -----
> + previewBitBltRules: rules on: aForm1 and: aForm2 fallback: fallbackForm scaledTo: aNumberOrPoint
> + 	"Returns a combined morph of the result of each rule applied on aForm1 combined with 
> + 	aForm2 scaled to aNumberOrPoint. If the combination faild with a rule, fallbackForm is 
> + 	shown instead. The number of each rule is appended at the bottom of each result."
> + 
> + 	| resultMorph tileExtent |
> + 	tileExtent := aNumberOrPoint asPoint.
> + 	resultMorph := Morph new
> + 		color: Color transparent;
> + 		extent: (rules size * tileExtent x)@tileExtent y;
> + 		yourself.
> + 
> + 	rules withIndexDo: [ :rule :index | | form formMorph numberLabel |
> + 		form := aForm1 copy.
> + 		[aForm2 copy displayOn: form at: 0 at 0 rule: rule]
> + 			on: Exception 
> + 			do: [form := fallbackForm].
> + 		formMorph := (form scaledToSize: tileExtent) asMorph
> + 			position: (index*tileExtent x)@0;
> + 			yourself.
> + 		resultMorph addMorph: formMorph.
> + 	
> + 		numberLabel := rule asString asMorph
> + 	      	center: ((index+0.5)*tileExtent x)@tileExtent y;
> + 			yourself.
> + 		resultMorph addMorph: numberLabel].
> + 
> + 	^ resultMorph!
> 
>