feat: Turtle.Morph() ( Fixes #154 )

Author: StartAutomating

Turtle.types.ps1xml

@@ -1082,6 +1082,107 @@ return $this.LSystem(
 
                     </Script>
       </ScriptMethod>
+      <ScriptMethod>
+        <Name>Morph</Name>
+        <Script>
+                        &lt;#
+.SYNOPSIS
+    Morphs a Turtle
+.DESCRIPTION
+    Morphs a Turtle by animating its path.
+
+    Any two paths with the same number of points can be morphed into each other.
+.EXAMPLE
+    $sierpinskiTriangle = turtle SierpinskiTriangle 42 4
+    $SierpinskiTriangleFlipped = turtle rotate 180 SierpinskiTriangle 42 4
+    turtle SierpinskiTriangle 42 4 morph (
+        $SierpinskiTriangle, 
+        $SierpinskiTriangleFlipped, 
+        $sierpinskiTriangle
+    ) save ./SierpinskiTriangleFlip.svg
+.EXAMPLE
+    $sideCount = (3..24 | Get-Random )
+    $stepCount = 36
+    
+    $flower = turtle rotate ((Get-Random -Max 180) * -1) flower 42 10 $sideCount $stepCount
+    $flower2 = turtle rotate ((Get-Random -Max 180)) flower 42 50 $sideCount $stepCount
+    $flower3 = turtle rotate ((Get-Random -Max 90)) flower 42 20 $sideCount $stepCount
+    turtle flower 42 10 $sideCount $stepCount duration ($sideCount * 3) morph ($flower, $flower2,$flower) |
+        save-turtle ./flowerMorph.svg Pattern
+.EXAMPLE
+    $flowerAngle = (40..60 | Get-Random )
+    $stepCount = 36
+    $radius = 23..42 | Get-Random
+    
+    $flowerPetals = turtle rotate ((Get-Random -Max 180) * -1) flowerPetal $radius 10 $flowerAngle $stepCount    
+    $flowerPetals3 = turtle rotate ((Get-Random -Max 180)) flowerPetal $radius 40 $flowerAngle $stepCount
+    turtle flowerPetal $radius 10 $flowerAngle $stepCount duration $radius morph (
+        $flowerPetals, 
+        $flowerPetals3,
+        $flowerPetals
+    ) | Save-Turtle ./flowerPetalMorph.svg Pattern
+#&gt;
+param(
+[Parameter(ValueFromRemainingArguments)]
+$Arguments
+)
+
+$durationArgument = $null
+
+$newPaths = @(foreach ($arg in $Arguments) {
+    if ($arg -is [string]) {
+        if ($arg -match '^\s{0,}m') {
+            $arg
+        }
+    } elseif ($arg.PathData) {
+        $arg.PathData
+    } elseif ($arg.D) {
+        $arg.D
+    } elseif ($arg -is [TimeSpan]) {
+        $durationArgument = $arg
+    }
+    elseif ($arg -is [double] -or $arg -is [int]) {
+        $durationArgument = [TimeSpan]::FromSeconds($arg)
+    }
+})
+
+if (-not $newPaths) {
+    return $this
+    &lt;#$pathSegments = @($this.PathData -split '(?=\p{L})')
+    $newPaths = @(for ($segmentNumber = 0; $segmentNumber -lt $pathSegments.Count; $segmentNumber++) {
+        $pathSegments[0..$segmentNumber] -join ' '
+    }) -join ';'#&gt;
+}
+
+if ($this.PathAnimation) {
+    $updatedAnimations = 
+        @(foreach ($animationXML in $this.PathAnimation -split '(?&lt;=/&gt;)') {
+            $animationXML = $animationXML -as [xml]
+            if (-not $animationXML) { continue }
+            if ($animationXML.attributeName -eq 'd') {
+                $animationXML.values = "$($newPaths -join ';')"
+            }
+            $animationXML.OuterXml
+        })
+    $this.PathAnimation = $updatedAnimations
+} else {
+    $this.PathAnimation += [Ordered]@{
+        attributeName = 'd'   ; values = "$($newPaths -join ';')" ; repeatCount = 'indefinite'; dur = $(
+            if ($durationArgument) {
+                "$($durationArgument.TotalSeconds)s"
+            } elseif ($this.Duration) {
+                "$($this.Duration.TotalSeconds)s"
+            } else {
+                "4.2s"
+            }
+            
+        )
+    }
+}
+
+return $this
+                    </Script>
+      </ScriptMethod>
       <ScriptMethod>
         <Name>PeanoCurve</Name>
         <Script>