grey/BOSL2
1
0
Fork 0
mirror of https://github.com/BelfrySCAD/BOSL2.git synced 2024-12-29 16:29:40 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Added patch_reverse()

Browse source
This commit is contained in:
Revar Desmera 2019-03-31 04:42:55 -07:00
parent 282207701a
commit d238236c59
1 changed files with 24 additions and 13 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

37
beziers.scad
View file

@ -226,7 +226,7 @@ function bezier_patch_point(patch, u, v) = bez_point([for (bez = patch) bez_poin
// Function: bezier_triangle_point() // Function: bezier_triangle_point()
// Usage: // Usage:
// bezier_triangle_point(patch, u, v) // bezier_triangle_point(tri, u, v)
// Description: // Description:
// Given a triangular 2-dimensional array of N+1 by (for the first row) N+1 points, // 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 // 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 // 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. // third, and 1 in the last row.
// Arguments: // 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 // 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`) // 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) = function bezier_triangle_point(tri, u, v) =
len(patch) == 1 ? patch[0][0] : len(tri) == 1 ? tri[0][0] :
let( let(
n = len(patch)-1, n = len(tri)-1,
Pu = [for(i=[0:n-1]) [for (j=[1:len(patch[i])-1]) patch[i][j]]], 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(patch[i])-2]) patch[i][j]]], Pv = [for(i=[0:n-1]) [for (j=[0:len(tri[i])-2]) tri[i][j]]],
Pw = [for(i=[1:len(patch)-1]) patch[i]] Pw = [for(i=[1:len(tri)-1]) tri[i]]
) )
bezier_triangle_point(u*Pu + v*Pv + (1-u-v)*Pw, u, v); 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() // Function: bezier_triangle()
// Usage: // Usage:
// bezier_triangle(patch, [splinesteps], [vertices], [faces]); // bezier_triangle(tri, [splinesteps], [vertices], [faces]);
// Description: // Description:
// Calculate vertices and faces for forming a partial polyhedron // Calculate vertices and faces for forming a partial polyhedron
// from the given bezier triangular patch. Returns a list containing // 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 // more vertices and faces for multiple bezier patches, to stitch
// them together into a complete polyhedron. // them together into a complete polyhedron.
// Arguments: // 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 // splinesteps = Number of steps to divide each bezier segment into. Default: 16
// vertices = Vertex list to add new points to. Default: [] // vertices = Vertex list to add new points to. Default: []
// faces = Face list to add new faces 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); // vnf = bezier_triangle(tri, splinesteps=16);
// polyhedron(points=vnf[0], faces=vnf[1]); // polyhedron(points=vnf[0], faces=vnf[1]);
function bezier_triangle(patch, splinesteps=16, vertices=[], faces=[]) = function bezier_triangle(tri, splinesteps=16, vertices=[], faces=[]) =
let( let(
base = len(vertices), base = len(vertices),
pts = [ pts = [
for ( for (
u=[0:splinesteps], u=[0:splinesteps],
v=[0:splinesteps-u] 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), new_vertices = concat(vertices, pts),
patchlen = len(patch), patchlen = len(tri),
tricnt = _tri_count(splinesteps+1), tricnt = _tri_count(splinesteps+1),
new_faces = [ new_faces = [
for ( 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() // Function: patch_translate()
// Usage: // Usage:
// patch_translate(patch, v) // patch_translate(patch, v)