feat: Turtle.ArcRight StepCount ( Fixes #272 )

Author: StartAutomating

Types/Turtle/ArcRight.ps1

@@ -15,7 +15,11 @@ $Radius = 10,
 
 # The angle of the arc
 [double]
-$Angle = 60
+$Angle = 60,
+
+# The number of steps.  If not provided, will default to half of the angle.
+[int]
+$StepCount
 )
 
 # Determine the absolute angle, for this operation
@@ -26,23 +30,30 @@ if ($absAngle -eq 0) { return $this }
 # Determine the circumference of a circle of this radius
 $Circumference = ((2 * $Radius) * [Math]::PI)
 
-# Clamp the angle, as arcs beyond 360 just continue to circle
-$ClampedAngle = 
-    if ($absAngle -gt 360) { 360 }
-    elseif ($absAngle -lt -360) { -360}
-    else { $absAngle }
-# The circumference step is the circumference divided by our clamped angle
-$CircumferenceStep = $Circumference / [Math]::Floor($ClampedAngle)
+# The circumference step is the circumference times 
+# the number of revolutions
+$revolutionCount = $angle/360
+# divided by the angle
+$CircumferenceStep = ($Circumference * $revolutionCount) / $Angle
+
 # The iteration is as close to one or negative one as possible
 $iteration  = $angle / [Math]::Floor($absAngle)
-# Start off at iteration 1
-$angleDelta = $iteration
-# while we have not reached the angle
-while ([Math]::Abs($angleDelta) -le $absAngle) {
-    # Rotate and move forward
-    $null = $this.Rotate($iteration).Forward($CircumferenceStep)
-    $angleDelta+=$iteration
+
+# If we have no step count
+if (-not $StepCount) {
+    # default to half of the angle.
+    $StepCount = [Math]::Round($absAngle / 2)    
+}
+# Turn this into a ratio (by default, this ratio would be `2`).
+$stepSize = $absAngle / $StepCount
+
+# Starting at zero, keep turning until we have reached the number.
+# Increase our angle by iteration * stepSize each time.
+for ($angleDelta = 0; [Math]::Abs($angleDelta) -lt $absAngle; $angleDelta+=($iteration*$stepSize)) {    
+    $this = $this. # In each step, 
+        Forward($CircumferenceStep*$StepSize). # move forward a fraction of the circumference,
+        Rotate($iteration*$StepSize) # and rotate a fraction of the total angle.
 }
 
-# Return this so we can keep the chain.
+# When we are done, return $this so we never break the chain.
 return $this