From d238236c59284565582b4214b1bff5816d001de6 Mon Sep 17 00:00:00 2001 From: Revar Desmera Date: Sun, 31 Mar 2019 04:42:55 -0700 Subject: [PATCH] Added patch_reverse() --- beziers.scad | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-) diff --git a/beziers.scad b/beziers.scad index 00ba0e6..219a5a8 100644 --- a/beziers.scad +++ b/beziers.scad @@ -226,7 +226,7 @@ function bezier_patch_point(patch, u, v) = bez_point([for (bez = patch) bez_poin // Function: bezier_triangle_point() // Usage: -// bezier_triangle_point(patch, u, v) +// bezier_triangle_point(tri, u, v) // Description: // Given a triangular 2-dimensional array of N+1 by (for the first row) N+1 points, // that represents a Bezier triangular patch of degree N, returns a point on @@ -234,16 +234,16 @@ function bezier_patch_point(patch, u, v) = bez_point([for (bez = patch) bez_poin // will have a list of 4 points in the first row, 3 in the second, 2 in the // third, and 1 in the last row. // Arguments: -// patch = Triangular bezier patch to get point on. +// tri = Triangular bezier patch to get point on. // u = The proportion of the way along the first dimension of the triangular patch to find the point of. 0<=`u`<=1 // v = The proportion of the way along the second dimension of the triangular patch to find the point of. 0<=`v`<=(1-`u`) -function bezier_triangle_point(patch, u, v) = - len(patch) == 1 ? patch[0][0] : +function bezier_triangle_point(tri, u, v) = + len(tri) == 1 ? tri[0][0] : let( - n = len(patch)-1, - Pu = [for(i=[0:n-1]) [for (j=[1:len(patch[i])-1]) patch[i][j]]], - Pv = [for(i=[0:n-1]) [for (j=[0:len(patch[i])-2]) patch[i][j]]], - Pw = [for(i=[1:len(patch)-1]) patch[i]] + n = len(tri)-1, + Pu = [for(i=[0:n-1]) [for (j=[1:len(tri[i])-1]) tri[i][j]]], + Pv = [for(i=[0:n-1]) [for (j=[0:len(tri[i])-2]) tri[i][j]]], + Pw = [for(i=[1:len(tri)-1]) tri[i]] ) bezier_triangle_point(u*Pu + v*Pv + (1-u-v)*Pw, u, v); @@ -296,7 +296,7 @@ function _tri_count(n) = (n*(1+n))/2; // Function: bezier_triangle() // Usage: -// bezier_triangle(patch, [splinesteps], [vertices], [faces]); +// bezier_triangle(tri, [splinesteps], [vertices], [faces]); // Description: // Calculate vertices and faces for forming a partial polyhedron // from the given bezier triangular patch. Returns a list containing @@ -306,7 +306,7 @@ function _tri_count(n) = (n*(1+n))/2; // more vertices and faces for multiple bezier patches, to stitch // them together into a complete polyhedron. // Arguments: -// patch = The triangular array of endpoints and control points for this bezier patch. +// tri = The triangular array of endpoints and control points for this bezier patch. // splinesteps = Number of steps to divide each bezier segment into. Default: 16 // vertices = Vertex list to add new points to. Default: [] // faces = Face list to add new faces to. Default: [] @@ -318,17 +318,17 @@ function _tri_count(n) = (n*(1+n))/2; // ]; // vnf = bezier_triangle(tri, splinesteps=16); // polyhedron(points=vnf[0], faces=vnf[1]); -function bezier_triangle(patch, splinesteps=16, vertices=[], faces=[]) = +function bezier_triangle(tri, splinesteps=16, vertices=[], faces=[]) = let( base = len(vertices), pts = [ for ( u=[0:splinesteps], v=[0:splinesteps-u] - ) bezier_triangle_point(patch, u/splinesteps, v/splinesteps) + ) bezier_triangle_point(tri, u/splinesteps, v/splinesteps) ], new_vertices = concat(vertices, pts), - patchlen = len(patch), + patchlen = len(tri), tricnt = _tri_count(splinesteps+1), new_faces = [ for ( @@ -370,6 +370,17 @@ function bezier_patch_flat(size=[100,100], N=4, orient=ORIENT_Z, trans=[0,0,0]) +// Function: patch_reverse() +// Usage: +// patch_reverse(patch) +// Description: +// Reverses the patch, so that the faces generated from it are flipped back to front. +// Arguments: +// patch = The patch to reverse. +function patch_reverse(patch) = [for (row=patch) reverse(row)]; + + + // Function: patch_translate() // Usage: // patch_translate(patch, v)