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Pseudo Hopf torus with holes
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# https://mathmod.deviantart.com/art/Pseudo-Hopf-Tori-565531249 | |
library(misc3d) | |
library(rgl) | |
cu <- cv <- 0.0000000001 | |
N <- 3 | |
Fx <- function(u,v){ -cos(u+v)/(sqrt(2)+cos(v-u)) } | |
DFx <- function(u,v){ | |
DFxu = (Fx(u,v)-Fx(u+cu,v))/cu | |
DFxv = (Fx(u,v)-Fx(u,v+cv))/cv | |
c(DFxu, DFxv) | |
} | |
Fy <- function(u,v){ sin(v-u)/(sqrt(2)+cos(v-u)) } | |
DFy <- function(u,v){ | |
DFyu = (Fy(u,v)-Fy(u+cu,v))/cu | |
DFyv = (Fy(u,v)-Fy(u,v+cv))/cv | |
c(DFyu, DFyv) | |
} | |
Fz <- function(u,v){ sin(u+v)/(sqrt(2)+cos(v-u)) } | |
DFz <- function(u,v){ | |
DFzu = (Fz(u,v)-Fz(u+cu,v))/cu | |
DFzv = (Fz(u,v)-Fz(u,v+cv))/cv | |
c(DFzu, DFzv) | |
} | |
n1 <- function(u,v){ | |
DFy(u,v)[1]*DFz(u,v)[2]-DFz(u,v)[1]*DFy(u,v)[2] | |
} | |
n2 <- function(u,v){ | |
DFz(u,v)[1]*DFx(u,v)[2]-DFx(u,v)[1]*DFz(u,v)[2] | |
} | |
n3 <- function(u,v){ | |
DFx(u,v)[1]*DFy(u,v)[2]-DFy(u,v)[1]*DFx(u,v)[2] | |
} | |
R <- function(u,v){ | |
sqrt(n1(u,v)^2+n2(u,v)^2+n3(u,v)^2) | |
} | |
fx <- function(u,v){ | |
Thickness = (abs(sin(15*u)*cos(15*v)))^7 + .4*((sin(2*N*u))) | |
Fx(u,v)+Thickness*n1(u,v)/R(u,v) | |
} | |
fy <- function(u,v){ | |
Thickness = (abs(sin(15*u)*cos(15*v)))^7 + .4*((sin(2*N*u))) | |
Fy(u,v)+Thickness*n2(u,v)/R(u,v) | |
} | |
fz <- function(u,v){ | |
Thickness = (abs(sin(15*u)*cos(15*v)))^7 + .4*((sin(2*N*u))) | |
Fz(u,v)+Thickness*n3(u,v)/R(u,v) | |
} | |
open3d(windowRect = c(50,50,562,562)) | |
parametric3d(Vectorize(fx), Vectorize(fy), Vectorize(fz), | |
umin=0, umax=pi, vmin=0, vmax=2*pi, n=300, | |
color="gold", engine="rgl", smooth = TRUE) | |
# # -- if you want an animation | |
M <- par3d("userMatrix") | |
movie3d( | |
par3dinterp( | |
time = seq(0, 1, len = 9), | |
userMatrix = list( | |
M, | |
rotate3d(M, pi, 1, 0, 0), | |
rotate3d(M, pi, 1, 1, 0), | |
rotate3d(M, pi, 1, 1, 1), | |
rotate3d(M, pi, 0, 1, 1), | |
rotate3d(M, pi, 0, 1, 0), | |
rotate3d(M, pi, 1, 0, 1), | |
rotate3d(M, pi, 0, 0, 1), | |
M | |
) | |
), | |
fps = 100, | |
duration = 1, | |
dir = ".", | |
movie = "zzpic", | |
convert = FALSE, webshot = FALSE | |
) | |
library(gifski) | |
gifski( | |
png_files = Sys.glob("zzpic*.png"), | |
gif_file = "PseudoHopfTorus.gif", | |
width = 512, | |
height = 512, | |
delay = 1/10 | |
) | |
file.remove(Sys.glob("zzpic*.png")) |
Author
stla
commented
Jun 17, 2023
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