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-# polysections
-
-Crosscutting a tube-like shape at different points gets several cross-sections. This module can operate reversely. It uses cross-sections to construct a tube-like shape. For example, imagine that you have the following cross-sections:
-
-![polysections](images/lib3x-polysections-1.JPG)
-
-This module can use them to construct the following model:
-
-![polysections](images/lib3x-polysections-2.JPG)
-
-Looks like extruding along the path? Yes, it can perform the task; however, it's more flexible. 
-
-You can also view it as a better polyline3d module if you want. If you have only the points of a path, using `polyline3d` or `hull_polyline3d` is a simple solution. If you know the cross sections along a path, you can use `polysections` to do more. 
-
-When using this module, you should use points to represent each cross section. The points of your cross section should have count-clockwise indexes. For example:
-
-![polysections](images/lib3x-polysections-10.JPG)
-
-If your cross section is hollow, set the `triangles` parameter to `"HOLLOW"` and index the points as the following:
-
-![polysections](images/lib3x-polysections-5.JPG)
-
-You can cut triangles by yourself. For example, the above shape can be cut into triangles such as:
-
-![polysections](images/lib3x-polysections-6.JPG)
-
-The indexes of the above triangles is:
-
-    [
-		[0, 3, 1],
-		[1, 3, 4],
-		[1, 4, 2],
-		[2, 4, 5],
-		[2, 5, 0],
-		[0, 5, 3]
-	]
-
-When defining triangles, you can use clockwise or counter-clockwise indexes. 
-
-## Parameters
-
-- `sections` : A list of cross-sections. Each cross-section is represented by a list of points. See the example below.
-- `triangles` : `"SOLID"` (default), `"HOLLOW"`,  or user-defined indexes. See example below.
-
-## Examples
-
-	use <rotate_p.scad>;
-	use <polysections.scad>;
-
-	section1 = [
-		[20, 0, 0],
-		[18, 9, 0],
-		[15, 10, 0],
-		[10, 0, 0]
-	];
-
-	// spin section1
-	sections = [
-		for(i = [0:55]) 
-			[
-				for(p = section1)
-					let(pt = rotate_p(p, [90, 0, 10 * i]))
-					[pt[0], pt[1] , pt[2] + i]
-			]
-	];
-
-	polysections(sections);
-
-![polysections](images/lib3x-polysections-7.JPG)
-
-	use <rotate_p.scad>;
-	use <polysections.scad>;
-	
-	section1 = [
-	    // outer
-		[20, 0, 0],
-		[18, 9, 0],
-		[15, 10, 0],
-		[10, 0, 0],
-	    // inner
-        [18, 2, 0],
-        [17, 7, 0],
-        [15, 7, 0],
-	    [12, 2, 0]
-	];
-	
-	// spin section1
-	sections = [
-	    for(i = [0:55]) 
-	        [
-	            for(p = section1)
-	                let(pt = rotate_p(p, [90, 0, 10 * i]))
-	                [pt[0], pt[1] , pt[2] + i]
-	        ]
-	];
-	    
-	polysections(sections, "HOLLOW");
-
-![polysections](images/lib3x-polysections-8.JPG)
-
-	use <rotate_p.scad>;
-	use <polysections.scad>;
-	
-	section1 = [
-	    // outer
-        [30, 0, 0],
-	    [15, 10, 0],
-	    [10, 0, 0],
-	    // inner
-	    [26, 1, 0],
-	    [15, 8, 0],
-	    [12, 1, 0],        
-	];
-	
-	// spin section1
-	sections = [
-	    for(i = [0:55]) 
-	        [
-	            for(p = section1)
-	                let(pt = rotate_p(p, [90, 0, 10 * i]))
-	                [pt[0], pt[1] , pt[2] + i]
-	        ]
-	];
-	    
-	polysections(
-	   sections = sections, 
-	   triangles = [
-            [0, 3, 1],
-            [1, 3, 4],
-            [1, 4, 2],
-            [2, 4, 5],
-            [2, 5, 0],
-            [0, 5, 3]
-        ]
-	);
-
-![polysections](images/lib3x-polysections-9.JPG)
-
-
-
-