59 lines
No EOL
2.5 KiB
OpenSCAD
59 lines
No EOL
2.5 KiB
OpenSCAD
module extrusion(points){
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//points[0] must have its points ordered clockwise
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n = len(points);
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k = len(points[0]);
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points_new = [for(L = points) for(p = L) p];
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faces = concat([[for(i = [0 : k-1]) i], [for(i = [1 : k]) (n*k)-i]],
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concat([for (i = [0 : n-2]) for (j = [0 : k-2]) [(i*k)+j+1, (i*k)+j, ((i+1)*k)+j, ((i+1)*k)+j+1]], [for (i = [0 : n-2]) [i*k,(i+1)*k-1,((i+2)*k)-1,(i+1)*k]]));
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polyhedron(points = points_new, faces = faces, convexity = 10);
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}
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module slice(points){
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k = len(points[0]);
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points_new = [for(L = points) for(p = L) p];
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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]]);
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polyhedron(points = points_new, faces = faces, convexity = 10);
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}
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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){
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B_0 = ctrl[0];
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B_1 = 3*(-ctrl[0] + ctrl[1]);
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B_2 = 3*(ctrl[0] - 2*ctrl[1] + ctrl[2]);
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B_3 = -ctrl[0] + 3*(ctrl[1] - ctrl[2]) + ctrl[3];
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function bezier(t) = B_0 + t*B_1 + (t^2)*B_2 + (t^3)*B_3;
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Bn_0 = [B_1.y,-B_1.x];
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Bn_1 = [2*B_2.y,(-2)*B_2.x];
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Bn_2 = [3*B_3.y,(-3)*B_3.x];
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function normal(t) = Bn_0 + t*Bn_1 + (t^2)*Bn_2;
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slices = [for (i = [0 : sections])
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let (t = i/sections, p = bezier(t), normal = normal(t), n = normal/norm(normal))
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[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]]];
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for(i = [0 : 1+gap : sections-merlon]){
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slice([slices[i],slices[i+merlon]]);
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}
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}
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module bezier_extrude(ctrl, shape, mod = function (t) 1, mod_x = function(t) 1, mod_y = function (t) 1, sections = 128){
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B_0 = ctrl[0];
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B_1 = 3*(-ctrl[0] + ctrl[1]);
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B_2 = 3*(ctrl[0] - 2*ctrl[1] + ctrl[2]);
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B_3 = -ctrl[0] + 3*(ctrl[1] - ctrl[2]) + ctrl[3];
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function bezier(t) = B_0 + t*B_1 + (t^2)*B_2 + (t^3)*B_3;
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Bn_0 = [B_1.y,-B_1.x];
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Bn_1 = [2*B_2.y,(-2)*B_2.x];
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Bn_2 = [3*B_3.y,(-3)*B_3.x];
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function normal(t) = Bn_0 + t*Bn_1 + (t^2)*Bn_2;
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slices = [for (i = [0 : sections])
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let (t = i/sections, p = bezier(t), normal = normal(t), n = normal/norm(normal))
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[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]]];
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extrusion(slices);
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}
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shape = [[0,0.5],[0.8,0],[0.5,-1],[-0.5,-1],[-0.8,0]];
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ctrl = [[0,0],[20,10],[0,20],[10,0]];
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wave = function (x) 0.75+0.25*cos(3*360*x);
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bezier_extrude_partial(ctrl = ctrl, shape = shape, mod = wave, sections = 32); |