Visualizing non-convex polygons

[ZiguoAtGitHub]

Hi Marco,
I want to plot a H-shape face. But I got this. Maybe there is a bug. :)

"""Set custom lights to a 3D scene"""

from vedo import *
B,D,TF,TW,BB,TFB=500,800,50,35,650,20
plist=[(-B/2.0,D/2.0),(B/2.0,D/2.0),(B/2.0,D/2-TF),(TW/2.0,D/2-TF),(TW/2.0,-D/2+TFB),(BB/2.0,-D/2+TFB),
         (BB/2.0,-D/2),(-BB/2.0,-D/2),(-BB/2.0,-D/2+TFB),(-TW/2.0,-D/2+TFB),(-TW/2.0,D/2-TF),(-B/2.0,D/2-TF)]
ndlist=[(ip[0],ip[1],0.0) for ip in plist]
# Add light sources at the given positions
mesh=Mesh([ndlist,[(0,1,2,3,4,5,6,7,8,9,10,11,0)]])

show(mesh, __doc__, axes=1, viewup='z').close()

[marcomusy]

I would write it as:

from vedo import *
B, D, TF, TW, BB, TFB = 500, 800, 50, 35, 650, 20
plist = [
    (-B / 2, D / 2),
    (B / 2, D / 2),
    (B / 2, D / 2 - TF),
    (TW / 2, D / 2 - TF),
    (TW / 2, -D / 2 + TFB),
    (BB / 2, -D / 2 + TFB),
    (BB / 2, -D / 2),
    (-BB / 2, -D / 2),
    (-BB / 2, -D / 2 + TFB),
    (-TW / 2, -D / 2 + TFB),
    (-TW / 2, D / 2 - TF),
    (-B / 2, D / 2 - TF),
]
faces = [(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)]
msh = Mesh([plist, faces]).triangulate().c("blue4").lw(1)
show(msh, axes=1).close()

do not repeat 0 to define the single face. Note that a single face which is not convex cannot be rendered, so you need .triangulate().

Hope this helps.

[ZiguoAtGitHub]

Thanks for your reply. :)
I have another solution:

from vedo import *

B,D,TF,TW,BB,TFB=500,800,50,35,650,20
plist=[(-B/2.0,D/2.0),(B/2.0,D/2.0),(B/2.0,D/2-TF),(TW/2.0,D/2-TF),(TW/2.0,-D/2+TFB),(BB/2.0,-D/2+TFB),
         (BB/2.0,-D/2),(-BB/2.0,-D/2),(-BB/2.0,-D/2+TFB),(-TW/2.0,-D/2+TFB),(-TW/2.0,D/2-TF),(-B/2.0,D/2-TF)]
ndlist=[(ip[0],ip[1],0.0) for ip in plist]
t_coord=[((iv[0]+250)/500,(iv[1]+400)/800) for iv in ndlist]
mesh2=Mesh([ndlist,[(0,1,2,11)]]).c('blue')
mesh1=Mesh([ndlist,[(10,3,4,9)]]).c('blue')
mesh3=Mesh([ndlist,[(8,5,6,7)]]).c('blue')
mesh1.clean()
mesh2.clean()
mesh3.clean()
mesh4=merge([mesh1,mesh2,mesh3])
show(mesh4, __doc__, axes=1, viewup='y').close()

[ZiguoAtGitHub]

Oh, please forget the t_coord list which is prepared for texture. :)

[marcomusy]

yes - note that in this case you don't need clean()