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docs/lib2-px_polyline.md

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+# px_polyline
+
+Given a list of points. `px_line` returns points that can be used to draw a pixel-style polyline.
+
+**Since:** 2.0
+
+## Parameters
+
+The dir changed since 2.0. 
+
+- `points` : A list of points. Each point can be `[x, y]` or `[x, y, z]`. x, y, z must be integer.
+
+## Examples
+
+	include <pixel/px_line.scad>;
+	include <pixel/px_polyline.scad>;
+	include <shape_pentagram.scad>;
+
+	pentagram = [
+		for(pt = shape_pentagram(15)) 
+			[round(pt[0]), round(pt[1])]
+	];
+
+	for(pt = px_polyline(concat(pentagram, [pentagram[0]]))) {
+		translate(pt) 
+			linear_extrude(1, scale = 0.5) 
+			    square(1, center = true);
+	}
+
+![px_polyline](images/lib2-px_polyline-1.JPG)
+
+	include <pixel/px_line.scad>;
+	include <pixel/px_polyline.scad>;
+	include <rotate_p.scad>;
+	include <sphere_spiral.scad>;
+
+	points_angles = sphere_spiral(
+		radius = 20, 
+		za_step = 5
+	);
+
+	points = [
+		for(pa = points_angles) 
+		let(pt = pa[0])
+		[round(pt[0]), round(pt[1]), round(pt[2])]
+	];
+
+	for(a = [0:30:330]) { 
+		rotate(a) 
+			for(pt = px_polyline(points)) {
+				translate(pt)
+					cube(1, center = true);
+			}
+	}
+		
+![px_polyline](images/lib2-px_polyline-2.JPG)
+