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changes after review

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SmoothieAq
2021-03-14 12:48:14 +01:00
parent 240334784d
commit 573c50774b
3 changed files with 21 additions and 43 deletions
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35
utils/rounded_polygon.scad
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@@ -41,8 +41,8 @@ function rounded_polygon_arcs(points, tangents) = //! Compute the arcs at the po
len = len(points)
) [ for (i = [0: len-1])
let(
p1 = tangents[(i - 1 + len) % len].y,
p2 = tangents[i].x,
p1 = tangents[(i - 1 + len) % len][1],
p2 = tangents[i][0],
p = points[i],
v1 = p1 - p,
v2 = p2 - p,
@@ -57,44 +57,23 @@ function rounded_polygon_arcs(points, tangents) = //! Compute the arcs at the po
) [a, v, l]
];
// we might want to remove the old rounded_polygon_tangents and to change rounded_polygon_length to use the v2 tangents
function rounded_polygon_tangents_v2(points) = //! Compute the straight sections between a point and the next point, for each section [start_point, end_point, length]
function rounded_polygon_tangents(points) = //! Compute the straight sections between a point and the next point, for each section [start_point, end_point, length]
let(len = len(points))
[ for(i = [0 : len - 1])
let(ends = circle_tangent(points[i], points[(i + 1) % len]))
[ends.x, ends.y, norm(ends.x - ends.y)]
[ends[0], ends[1], norm(ends[0] - ends[1])]
];
function rounded_polygon_tangents(points) = //! Compute the straight sections between a point and the next point, needed to draw and to compute the lengths
let(len = len(points))
[for(i = [0 : len - 1])
let(ends = circle_tangent(points[i], points[(i + 1) % len]))
for(end = [0, 1])
ends[end]];
//function sumv(v, i = 0, sum = 0) = i == len(v) ? sum : sumv(v, i + 1, sum + v[i]); // moved to maths.scad
// the cross product of 2D vectors is the area of the parallelogram between them. We use the sign of this to decide if the angle is bigger than 180.
function rounded_polygon_length(points, tangents) = //! Calculate the length given the point list and the list of tangents computed by ` rounded_polygon_tangents`
let(
len = len(points),
indices = [0 : len - 1],
straights = [for(i = indices) norm(tangents[2 * i] - tangents[2 * i + 1])],
arcs = [for(i = indices) let(p1 = tangents[2 * i + 1],
p2 = tangents[(2 * i + 2) % (2 * len)],
corner = points[(i + 1) % len],
c = [corner.x, corner.y],
v1 = p1 - c,
v2 = p2 - c,
r = abs(corner.z),
a = acos((v1 * v2) / sqr(r))) r ? PI * (cross(v1, v2) <= 0 ? a : 360 - a) * r / 180 : 0]
)
sumv(concat(straights, arcs));
arcs = rounded_polygon_arcs(points, tangents)
) sumv( map( concat(tangents, arcs), function(e) e[2] ) );
module rounded_polygon(points, _tangents = undef) { //! Draw the rounded polygon from the point list, can pass the tangent list to save it being calculated
len = len(points);
indices = [0 : len - 1];
tangents = _tangents ? _tangents : rounded_polygon_tangents(points);
tangents = [ for (t = _tangents ? _tangents : rounded_polygon_tangents(points)) each [t.x, t.y] ];
difference(convexity = points) {
union() {