unified bezier_extrude_partial with bezier_extrude

This commit is contained in:
tessaK9 2026-03-13 23:42:04 +01:00
commit 0c97fa8e0a
2 changed files with 14 additions and 33 deletions

View file

@ -8,14 +8,7 @@ module extrusion(points){
polyhedron(points = points_new, faces = faces, convexity = 10); polyhedron(points = points_new, faces = faces, convexity = 10);
} }
module slice(points){ module bezier_extrude(ctrl, shape, mod = function (t) 1, mod_x = function(t) 1, mod_y = function (t) 1, partial = false, merlon = 1, gap = 1, sections = 128){
k = len(points[0]);
points_new = [for(L = points) for(p = L) p];
faces = concat([[for(i = [0 : k-1]) i], [for(i = [1 : k]) 2*k-i], [0,k-1,(2*k)-1,k]], [for (i = [0 : k-2]) [i+1, i, k+i, k+i+1]]);
polyhedron(points = points_new, faces = faces, convexity = 10);
}
module bezier_extrude_partial(ctrl, shape, merlon = 1, gap = 1, mod = function (t) 1, mod_x = function(t) 1, mod_y = function (t) 1, sections = 128){
B_0 = ctrl[0]; B_0 = ctrl[0];
B_1 = 3*(-ctrl[0] + ctrl[1]); B_1 = 3*(-ctrl[0] + ctrl[1]);
B_2 = 3*(ctrl[0] - 2*ctrl[1] + ctrl[2]); B_2 = 3*(ctrl[0] - 2*ctrl[1] + ctrl[2]);
@ -30,30 +23,18 @@ module bezier_extrude_partial(ctrl, shape, merlon = 1, gap = 1, mod = function
slices = [for (i = [0 : sections]) slices = [for (i = [0 : sections])
let (t = i/sections, p = bezier(t), normal = normal(t), n = normal/norm(normal)) let (t = i/sections, p = bezier(t), normal = normal(t), n = normal/norm(normal))
[for (v = shape) [p.x+(mod(t) * mod_x(t) * n.x * v.x),p.y+(mod(t) * mod_x(t) * n.y * v.x), mod(t) * mod_y(t) * v.y]]]; [for (v = shape) [p.x+(mod(t) * mod_x(t) * n.x * v.x),p.y+(mod(t) * mod_x(t) * n.y * v.x), mod(t) * mod_y(t) * v.y]]];
for(i = [0 : 1+gap : sections-merlon]){ if(partial){
slice([slices[i],slices[i+merlon]]); for(i = [0 : merlon+gap : sections-merlon]){
extrusion([slices[i],slices[i+merlon]]);
}
}
else{
extrusion(slices);
} }
} }
module bezier_extrude(ctrl, shape, mod = function (t) 1, mod_x = function(t) 1, mod_y = function (t) 1, sections = 128){
B_0 = ctrl[0];
B_1 = 3*(-ctrl[0] + ctrl[1]);
B_2 = 3*(ctrl[0] - 2*ctrl[1] + ctrl[2]);
B_3 = -ctrl[0] + 3*(ctrl[1] - ctrl[2]) + ctrl[3];
function bezier(t) = B_0 + t*B_1 + (t^2)*B_2 + (t^3)*B_3;
Bn_0 = [B_1.y,-B_1.x];
Bn_1 = [2*B_2.y,(-2)*B_2.x];
Bn_2 = [3*B_3.y,(-3)*B_3.x];
function normal(t) = Bn_0 + t*Bn_1 + (t^2)*Bn_2;
slices = [for (i = [0 : sections])
let (t = i/sections, p = bezier(t), normal = normal(t), n = normal/norm(normal))
[for (v = shape) [p.x+(mod(t) * mod_x(t) * n.x * v.x),p.y+(mod(t) * mod_x(t) * n.y * v.x), mod(t) * mod_y(t) * v.y]]];
extrusion(slices);
}
shape = [[0,0.5],[0.8,0],[0.5,-1],[-0.5,-1],[-0.8,0]]; shape = [[0,0.5],[0.8,0],[0.5,-1],[-0.5,-1],[-0.8,0]];
ctrl = [[0,0],[20,10],[0,20],[10,0]]; ctrl = [[0,0],[0,20],[20,20],[20,0]];
wave = function (x) 0.75+0.25*cos(3*360*x); wave1 = function (x) 0.75+0.25*cos(8*360*x);
bezier_extrude_partial(ctrl = ctrl, shape = shape, mod = wave, sections = 32); wave2 = function (x) 0.75+0.25*sin(8*360*x);
bezier_extrude(ctrl = ctrl, shape = shape, mod_x = wave1, mod_y = wave2, partial = true, merlon = 3, gap = 1, sections = 128);

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@ -37,9 +37,9 @@ module headband(thickness, height){
} }
mirror([1,0,0]) bezier_extrude(ctrl = ctrl_end, shape = shape_band, sections = 16); mirror([1,0,0]) bezier_extrude(ctrl = ctrl_end, shape = shape_band, sections = 16);
translate([-17,-8]){ translate([-17,-8]){
rotate_extrude(convexity = 10, $fn = 16) polygon(shape_halfband); rotate_extrude(convexity = 10, $fn = 9) polygon(shape_halfband);
} }
bezier_extrude_partial(ctrl = ctrl_rake, shape = shape_rake, merlon = 2, gap = 3, sections = 5*42+1 ); bezier_extrude(ctrl = ctrl_rake, shape = shape_rake, partial = true, merlon = 2, gap = 3, sections = 5*42+1 );
} }
} }