dotSCAD/docs/lib3x-along_with.md

# along_with

If you want to place objects precisely, their points and angles are required. When you have only points or you don't care their precise angles, `along_with` puts children along the given path. If there's only one child, it will put the child for each point. 

## Parameters

- `points` : The points along the path. 
- `angles` : Rotate before translate each child. If not given, rotate children automatically according to `points` and `method`.
- `twist` : If given, each child will be twisted before applying each element of `points` and `angles`.
- `scale` : If given, each child will be scaled before applying each element of `points` and `angles`. It accepts a single value, `[sx, sy]` or `[sx, sy, sz]`.
- `method` : Which method does `along_with` take to **guess** how to rotate children if `angles` is not specified? It accepts two value, `"AXIS_ANGLE"` (default) and `"EULER_ANGLE"`. See `path_extrude` for more information. **Since:** 1.3

## Examples

	use <along_with.scad>
	use <shape_circle.scad>
	
	$fn = 24;
	
	points = shape_circle(radius = 50);
	
	along_with(points) 
	    sphere(5);

![along_with](images/lib3x-along_with-1.JPG)

	use <along_with.scad>
	use <shape_circle.scad>

	$fn = 24;

	points = shape_circle(radius = 50);

	along_with(points) {
		linear_extrude(10, center = true) text("A", valign = "center", halign = "center");
		linear_extrude(5, center = true) circle(2);
		sphere(1);
		cube(5);
		linear_extrude(10, center = true) text("A", valign = "center", halign = "center");
		linear_extrude(5, center = true) circle(2);
		sphere(1);
		cube(5);        
	}

![along_with](images/lib3x-along_with-2.JPG)

	use <along_with.scad>
	use <golden_spiral.scad>

	pts_angles = golden_spiral(
		from = 5, 
		to = 11, 
		point_distance = 4
	);

	points = [for(p_a = pts_angles) p_a[0]];
	angles = [for(p_a = pts_angles) p_a[1]];

	along_with(points, angles)
	rotate([90, 0, 0]) 
	linear_extrude(1, center = true) 
		text("A", valign = "center", halign = "center");

![along_with](images/lib3x-along_with-3.JPG)

	use <bezier_curve.scad>
	use <along_with.scad>

	module scales() {
		module one_scale() {
			rotate([0, 60, 0]) 
			linear_extrude(1, center = true) 
			scale([2, 1]) 
				circle(1.25, $fn = 24);    
		}

		for(a = [0:30:330]) {
			rotate(a) 
			translate([5, 0, 0]) 
				one_scale();

			rotate(a + 15) 
			translate([5, 0, 1.75]) 
				one_scale();
		}
	}

	t_step = 0.01;

	p0 = [0, 0, 0];
	p1 = [0, 50, 35];
	p2 = [-100, 70, 0];
	p3 = [30, 120, -35];
	p4 = [30, 150, -40];
	p5 = [0, 200, -3];

	path_pts = bezier_curve(t_step, 
		[p0, p1, p2, p3, p4, p5]
	);

	along_with(path_pts, scale = 0.5)  
		scales();

![along_with](images/lib3x-along_with-4.JPG)