Add write-fractal.ps1

Scripts/write-fractal.ps1

@@ -0,0 +1,60 @@
+<#
+.SYNOPSIS
+        Writes a fractal
+.DESCRIPTION
+        This PowerShell script writes an animated Mandelbrot fractal.
+.EXAMPLE
+        PS> ./write-fractal
+.LINK
+        https://github.com/fleschutz/PowerShell
+.NOTES
+        Author: Markus Fleschutz | License: CC0
+#>
+
+function CalculateFractal([float]$left, [float]$top, [float]$xside, [float]$yside, [float]$zoom) { 
+	[int]$maxx = $rui.MaxWindowSize.Width
+	[int]$maxy = $rui.MaxWindowSize.Height
+	[float]$xscale = $xside / $maxx 
+	[float]$yscale = $yside / $maxy 
+	for ([int]$y = 0; $y -lt $maxy; $y++) { 
+		for ([int]$x = 0; $x -lt $maxx; $x++) { 
+			[float]$cx = $x * $xscale + $left
+			[float]$cy = $y * $yscale + $top
+			[float]$zx = 0
+			[float]$zy = 0
+			for ([int]$count = 0; ($zx * $zx + $zy * $zy -lt 4) -and ($count -lt $MAXCOUNT); $count++) { 
+				[float]$tempx = $zx * $zx - $zy * $zy + $cx
+				$zy = $zoom * $zx * $zy + $cy
+				$zx = $tempx
+			} 
+			$global:buffer[$y * $maxx + $x] = $([char](65 + $count))
+		} 
+	}
+}
+
+$MAXCOUNT = 30 
+$ui = (Get-Host).ui
+$rui = $ui.rawui
+[float]$left = -1.75 
+[float]$top = -0.25 
+[float]$xside = 0.25 
+[float]$yside = 0.45 
+$buffer0 = ""
+1..($rui.MaxWindowSize.Width * $rui.MaxWindowSize.Height) | ForEach-Object { $buffer0 += " " }
+$global:buffer = $buffer0.ToCharArray()
+
+while ($true) {
+	for ([float]$zoom = 4.0; $zoom -gt 1.1; $zoom -= 0.02) {
+		CalculateFractal $left $top $xside $yside $zoom
+		[console]::SetCursorPosition(0,0)
+		[string]$drawscreen = New-Object system.string($global:buffer, 0, $global:buffer.Length)
+		Write-Host -foreground green $drawscreen -noNewline
+	}
+	for ([float]$zoom = 1.1; $zoom -lt 4.0; $zoom += 0.02) {
+		CalculateFractal $left $top $xside $yside $zoom
+		[console]::SetCursorPosition(0,0)
+		[string]$drawscreen = New-Object system.string($global:buffer, 0, $global:buffer.Length)
+		Write-Host -foreground green $drawscreen -noNewline
+	}
+}
+exit 0 # success