Cairo matrix: add copy and newFrom + tests

src/Alexandrie-Cairo-Tests/AeCairoMatrixTest.class.st

@@ -39,6 +39,26 @@ AeCairoMatrixTest >> testBeMultiplicationOfBy [
 		closeTo: (AeCairoMatrix newX: 0.2 y: 0.6 sx: 0.6 sy: 1.2 shx: 1.0 shy: 1.8)
 ]
 
+{ #category : #tests }
+AeCairoMatrixTest >> testCopy [
+
+	| aCopy |
+	matrix := AeCairoMatrix newX: 0.1 y: 0.2 sx: 0.3 sy: 0.4 shx: 0.5 shy: 0.6.
+	aCopy := matrix copy.
+
+	"Check independent change"
+	matrix x: 17.
+	aCopy  x: 23.
+	self assert: matrix x equals: 17.
+	self assert: aCopy x  equals: 23.
+
+	"Other factors match"
+	self assert: matrix sx  equals: 0.3.
+	self assert: matrix sy  equals: 0.4.
+	self assert: matrix shx equals: 0.5.
+	self assert: matrix shy equals: 0.6
+]
+
 { #category : #tests }
 AeCairoMatrixTest >> testCreation [ 
 
@@ -71,6 +91,26 @@ AeCairoMatrixTest >> testIsIdentity [
 
 ]
 
+{ #category : #tests }
+AeCairoMatrixTest >> testNewFrom [
+
+	| aCopy |
+	matrix := AeCairoMatrix newX: 0.1 y: 0.2 sx: 0.3 sy: 0.4 shx: 0.5 shy: 0.6.
+	aCopy := AeCairoMatrix newFrom: matrix.
+
+	"Check independent change"
+	matrix x: 17.
+	aCopy  x: 23.
+	self assert: matrix x equals: 17.
+	self assert: aCopy x  equals: 23.
+
+	"Other factors match"
+	self assert: matrix sx  equals: 0.3.
+	self assert: matrix sy  equals: 0.4.
+	self assert: matrix shx equals: 0.5.
+	self assert: matrix shy equals: 0.6
+]
+
 { #category : #test }
 AeCairoMatrixTest >> testNewRotationByRadians [
 

src/Alexandrie-Cairo/AeCairoMatrix.class.st

@@ -57,6 +57,18 @@ AeCairoMatrix class >> multiply: a by: b into: result [
 			AeCairoMatrix * b ) )
 ]
 
+{ #category : #'instance creation' }
+AeCairoMatrix class >> newFrom: aSimilarObject [
+
+	^ self
+		  newX: aSimilarObject x
+		  y: aSimilarObject y
+		  sx: aSimilarObject sx
+		  sy: aSimilarObject sy
+		  shx: aSimilarObject shx
+		  shy: aSimilarObject shy
+]
+
 { #category : #'instance creation' }
 AeCairoMatrix class >> newIdentity [
 
@@ -235,6 +247,12 @@ AeCairoMatrix >> closeTo: anotherMatrix precision: num [
 						and: [ self y closeTo: anotherMatrix y precision: num ] ] ] ] ]
 ]
 
+{ #category : #copying }
+AeCairoMatrix >> copy [
+
+	^ self class newFrom: self
+]
+
 { #category : #comparing }
 AeCairoMatrix >> hash [