feat: Turtle.Spiderweb ( Fixes #290 )

Author: StartAutomating

Types/Turtle/Spiderweb.ps1

@@ -0,0 +1,153 @@
+<#
+.SYNOPSIS
+    Draws a spiderweb with a Turtle
+.DESCRIPTION
+    Tells our Turtle to draw a spiderweb.
+
+    This will draw any number of spokes, and draw a polygon between each spoke at regular intervals
+.EXAMPLE
+    # Draw a spiderweb
+    turtle spiderweb
+.EXAMPLE
+    # Draw a spider web with a radius six
+    # containing six rings
+    # along six spokes
+    turtle spiderweb 6 6 6 show
+.EXAMPLE
+    # Draw a random spiderweb
+    turtle rotate (
+        Get-Random -Max 360
+    ) web 42 (
+        Get-Random -Min 3 -Max 13
+    ) (
+        Get-Random -Min 3 -Max 13
+    ) save ./RandomWeb.svg show
+.EXAMPLE
+    turtle rotate (
+        Get-Random -Max 360
+    ) web 42 (
+        Get-Random -Min 3 -Max 13
+    ) (
+        Get-Random -Min 3 -Max (13 * 3)
+    ) pathAnimation (
+        [Ordered]@{
+            type = 'rotate'   ; values = 0, 360 ;repeatCount = 'indefinite'; dur = "41s"
+        }
+    ) save ./RandomWebRotate.svg show
+.EXAMPLE
+    turtle rotate (
+        Get-Random -Max 360
+    ) web 42 (
+        Get-Random -Min 3 -Max 13
+    ) (
+        Get-Random -Min 3 -Max (13 * 3)
+    ) pathAnimation (
+        [Ordered]@{
+            type = 'rotate'   ; values = 0, 360 ;repeatCount = 'indefinite'; dur = "41s"
+        }
+    ) backgroundcolor 'black' stroke 'yellow' pathclass 'yellow-stroke' save ./RandomWebRotateColor.svg show     
+.EXAMPLE
+    turtle rotate (
+        Get-Random -Max 360
+    ) web 42 (
+        Get-Random -Min 3 -Max 13
+    ) (
+        Get-Random -Min 3 -Max (13 * 3)
+    ) morph save ./RandomWebStepMorph.svg
+.EXAMPLE
+    $spokes = Get-Random -Min 3 -Max 13
+    $rings =  Get-Random -Min 3 -Max (13 * 3)
+    turtle web 42 $spokes $rings morph @(
+        turtle web 42 $spokes $rings 
+        turtle rotate (
+            Get-Random -Max 360
+        ) web 42 $spokes $rings 
+        turtle web 42 $spokes $rings 
+    ) save ./RandomWebMorph.svg
+.EXAMPLE
+    $spokes = Get-Random -Min 3 -Max 13
+    $rings =  Get-Random -Min 3 -Max (13 * 3)
+    turtle web 42 $spokes $rings morph @(
+        turtle web 42 $spokes $rings 
+        turtle rotate (
+            Get-Random -Max 360
+        ) web 42 $spokes $rings 
+        turtle web 42 $spokes $rings 
+    ) backgroundcolor 'black' stroke 'yellow' pathclass 'yellow-stroke' save ./RandomWebMorphColor.svg
+        
+#>
+param(
+# The radius of the web
+[double]
+$Radius = 42,
+
+# The number of spokes in the web.
+[int]
+$SpokeCount = 6,
+
+# The number of rings in the web.
+[int]
+$RingCount = 6
+)
+
+
+# If there were no spokes or rings, return this
+if ($spokeCount -eq 0 ) { return $this }
+if ($RingCount -eq 0 ) { return $this }
+
+
+# Determine the angle of the spokes
+$spokeAngle = 360 / $SpokeCount
+
+# And draw each spoke.
+foreach ($n in 1..$([Math]::Abs($SpokeCount))) {
+    $this = $this.Forward($radius).Backward($radius).Rotate($spokeAngle)
+}
+
+# Now we have the structure of our web, and we are at the center.
+$center = 
+    [Numerics.Vector2]::new($this.X, $this.Y)
+
+
+# Each ring we want to grow the in radius
+$radiusStep = $radius  / $RingCount
+$inRadius = 0
+
+# Starting from the center, we want to try to make a series of rings to each next point in the web
+foreach ($ringNumber in 1..$([Math]::Abs($RingCount))) {
+    $inRadius+=$radiusStep
+    # First, move along our spoke
+    $null = $this.Forward($radiusStep)
+
+    # Then get our bearings
+    $heading = $this.Heading
+
+    # and imagine points around a circle, along each of our spokes
+    $webPoints = @(
+        foreach ($spokeNumber in 1..$SpokeCount) {        
+            $heading += $spokeAngle                    
+            [Numerics.Vector2]::new(
+                $center.X + $inRadius * [math]::cos($heading * [Math]::PI / 180),
+                $center.Y + $inRadius * [math]::sin($heading * [Math]::PI / 180)
+            )        
+        }    
+    )
+
+    # Now that we have the points, 
+    foreach ($point in $webPoints) {
+        # our turtle spider can 
+        $this = $this.Rotate(
+            # rotate towards the point
+            $this.Towards($point.X, $point.Y)
+        ).Forward(
+            # and close the distance.
+            $this.Distance($point.X, $point.Y)
+        )
+    }
+
+    # Reset our bearings and head up to the next ring.
+    $this.Heading = $heading        
+}
+
+# Now that we've drawn our web, return ourself.
+return $this