From b0bcdade7efcb699a20b9b1083d3aa1cc7c468cc Mon Sep 17 00:00:00 2001 From: Adrian Mariano Date: Mon, 11 Oct 2021 22:57:19 -0400 Subject: [PATCH] doc tweaks --- regions.scad | 85 +++++++++++++++++++++++++++++----------------------- 1 file changed, 47 insertions(+), 38 deletions(-) diff --git a/regions.scad b/regions.scad index 5326c15..caf4f67 100644 --- a/regions.scad +++ b/regions.scad @@ -156,7 +156,7 @@ function point_in_region(point, region, eps=EPSILON, _i=0, _cnt=0) = // formed from a list of simple polygons that do not intersect each other. // Arguments: // region = region to check -// eps = tolerance for geometric omparisons. Default: `EPSILON` = 1e-9 +// eps = tolerance for geometric comparisons. Default: `EPSILON` = 1e-9 function is_region_simple(region, eps=EPSILON) = [for(p=region) if (!is_path_simple(p,closed=true,eps)) 1] == [] && @@ -286,7 +286,7 @@ function _region_region_intersections(region1, region2, closed1=true,closed2=tru // closed1 = if false then treat region1 as list of open paths. Default: true // closed2 = if false then treat region2 as list of open paths. Default: true // eps = Acceptable variance. Default: `EPSILON` (1e-9) -// Example: +// Example(2D): // path = square(50,center=false); // region = [circle(d=80), circle(d=40)]; // paths = split_region_at_region_crossings(path, region); @@ -706,64 +706,73 @@ function _point_dist(path,pathseg_unit,pathseg_len,pt) = // return_faces = return face list. Default: False. // firstface_index = starting index for face list. Default: 0. // flip_faces = flip face direction. Default: false -// Example(2D): +// Example(2D,NoAxes): // star = star(5, r=100, ir=30); -// #stroke(closed=true, star); -// stroke(closed=true, offset(star, delta=10, closed=true)); -// Example(2D): +// #stroke(closed=true, star, width=3); +// stroke(closed=true, width=3, offset(star, delta=10, closed=true)); +// Example(2D,NoAxes): // star = star(5, r=100, ir=30); -// #stroke(closed=true, star); -// stroke(closed=true, offset(star, delta=10, chamfer=true, closed=true)); -// Example(2D): +// #stroke(closed=true, star, width=3); +// stroke(closed=true, width=3, +// offset(star, delta=10, chamfer=true, closed=true)); +// Example(2D,NoAxes): // star = star(5, r=100, ir=30); -// #stroke(closed=true, star); -// stroke(closed=true, offset(star, r=10, closed=true)); -// Example(2D): -// star = star(5, r=100, ir=30); -// #stroke(closed=true, star); -// stroke(closed=true, offset(star, delta=-10, closed=true)); -// Example(2D): -// star = star(5, r=100, ir=30); -// #stroke(closed=true, star); -// stroke(closed=true, offset(star, delta=-10, chamfer=true, closed=true)); -// Example(2D): -// star = star(5, r=100, ir=30); -// #stroke(closed=true, star); -// stroke(closed=true, offset(star, r=-10, closed=true, $fn=20)); -// Example(2D): This case needs `quality=2` for success +// #stroke(closed=true, star, width=3); +// stroke(closed=true, width=3, +// offset(star, r=10, closed=true)); +// Example(2D,NoAxes): +// star = star(7, r=120, ir=50); +// #stroke(closed=true, width=3, star); +// stroke(closed=true, width=3, +// offset(star, delta=-15, closed=true)); +// Example(2D,NoAxes): +// star = star(7, r=120, ir=50); +// #stroke(closed=true, width=3, star); +// stroke(closed=true, width=3, +// offset(star, delta=-15, chamfer=true, closed=true)); +// Example(2D,NoAxes): +// star = star(7, r=120, ir=50); +// #stroke(closed=true, width=3, star); +// stroke(closed=true, width=3, +// offset(star, r=-15, closed=true, $fn=20)); +// Example(2D,NoAxes): This case needs `quality=2` for success // test = [[0,0],[10,0],[10,7],[0,7], [-1,-3]]; // polygon(offset(test,r=-1.9, closed=true, quality=2)); // //polygon(offset(test,r=-1.9, closed=true, quality=1)); // Fails with erroneous 180 deg path error // %down(.1)polygon(test); -// Example(2D): This case fails if `check_valid=true` when delta is large enough because segments are too close to the opposite side of the curve. +// Example(2D,NoAxes): This case fails if `check_valid=true` when delta is large enough because segments are too close to the opposite side of the curve. // star = star(5, r=22, ir=13); -// stroke(star,width=.2,closed=true); +// stroke(star,width=.3,closed=true); // color("green") -// stroke(offset(star, delta=-9, closed=true),width=.2,closed=true); // Works with check_valid=true (the default) +// stroke(offset(star, delta=-9, closed=true),width=.3,closed=true); // Works with check_valid=true (the default) // color("red") // stroke(offset(star, delta=-10, closed=true, check_valid=false), // Fails if check_valid=true -// width=.2,closed=true); +// width=.3,closed=true); // Example(2D): But if you use rounding with offset then you need `check_valid=true` when `r` is big enough. It works without the validity check as long as the offset shape retains a some of the straight edges at the star tip, but once the shape shrinks smaller than that, it fails. There is no simple way to get a correct result for the case with `r=10`, because as in the previous example, it will fail if you turn on validity checks. // star = star(5, r=22, ir=13); // color("green") // stroke(offset(star, r=-8, closed=true,check_valid=false), width=.1, closed=true); // color("red") // stroke(offset(star, r=-10, closed=true,check_valid=false), width=.1, closed=true); -// Example(2D): The extra triangles in this example show that the validity check cannot be skipped +// Example(2D,NoAxes): The extra triangles in this example show that the validity check cannot be skipped // ellipse = scale([20,4], p=circle(r=1,$fn=64)); // stroke(ellipse, closed=true, width=0.3); -// stroke(offset(ellipse, r=-3, check_valid=false, closed=true), width=0.3, closed=true); -// Example(2D): The triangles are removed by the validity check +// stroke(offset(ellipse, r=-3, check_valid=false, closed=true), +// width=0.3, closed=true); +// Example(2D,NoAxes): The triangles are removed by the validity check // ellipse = scale([20,4], p=circle(r=1,$fn=64)); // stroke(ellipse, closed=true, width=0.3); -// stroke(offset(ellipse, r=-3, check_valid=true, closed=true), width=0.3, closed=true); +// stroke(offset(ellipse, r=-3, check_valid=true, closed=true), +// width=0.3, closed=true); // Example(2D): Open path. The path moves from left to right and the positive offset shifts to the left of the initial red path. // sinpath = 2*[for(theta=[-180:5:180]) [theta/4,45*sin(theta)]]; -// #stroke(sinpath); -// stroke(offset(sinpath, r=17.5)); -// Example(2D): Region -// rgn = difference(circle(d=100), union(square([20,40], center=true), square([40,20], center=true))); -// #linear_extrude(height=1.1) for (p=rgn) stroke(closed=true, width=0.5, p); +// #stroke(sinpath, width=2); +// stroke(offset(sinpath, r=17.5),width=2); +// Example(2D,NoAxes): Region +// rgn = difference(circle(d=100), +// union(square([20,40], center=true), +// square([40,20], center=true))); +// #linear_extrude(height=1.1) stroke(rgn, width=1); // region(offset(rgn, r=-5)); function offset( path, r=undef, delta=undef, chamfer=false, @@ -936,8 +945,8 @@ function _filter_region_parts(region1, region2, keep1, keep2, eps=EPSILON) = // Example(2D): // shape1 = move([-8,-8,0], p=circle(d=50)); // shape2 = move([ 8, 8,0], p=circle(d=50)); -// for (shape = [shape1,shape2]) color("red") stroke(shape, width=0.5, closed=true); // color("green") region(union(shape1,shape2)); +// for (shape = [shape1,shape2]) color("red") stroke(shape, width=0.5, closed=true); function union(regions=[],b=undef,c=undef,eps=EPSILON) = b!=undef? union(concat([regions],[b],c==undef?[]:[c]), eps=eps) : len(regions)==0? [] :