2D Polar Rose with z*z?

 
Post new topic   Reply to topic    K3DSurf forum Forum Index -> Mathematical Models Collection
View previous topic :: View next topic  
Author Message
ufoace



Joined: 11 Mar 2013
Posts: 46

PostPosted: Sun Oct 13, 2013 9:35 am    Post subject: 2D Polar Rose with z*z? Reply with quote

Hi, it is possible to make a spiral with:
F(): 0.5 - z*z - sin((sqrt(x*x+y*y) - 0.5*atan2(y,x)))^2

and i have failed to make the same style for a polar rose, is it impossible?
just these using z*z for depth?



the spiral:
F(): 0.5 - z*z - sin((sqrt(x*x+y*y) - 0.5*atan2(y,x)))^2
Back to top View user's profile Send private message
denisc



Joined: 24 Apr 2013
Posts: 92

PostPosted: Sun Oct 13, 2013 3:35 pm    Post subject: Reply with quote

hello ufoace

With this formula, if you don't write x, y, and z limit

the result is very poor for me ,in K3Dsurf, a little slightly distorted ?


cheers
Back to top View user's profile Send private message Send e-mail
ufoace



Joined: 11 Mar 2013
Posts: 46

PostPosted: Sun Oct 13, 2013 8:49 pm    Post subject: Reply with quote

I had same in the pic, i rewrote it for a marching cubes engine and it was same. I'm silly because polar roses are parametric and i always work on isosurfaces. i can't believe that i didnt manage to emulate parametric for my marching cubes engine because normally you would run segments and += them to the total and i didnt!
Back to top View user's profile Send private message
denisc



Joined: 24 Apr 2013
Posts: 92

PostPosted: Mon Oct 14, 2013 9:54 am    Post subject: Reply with quote

hello uoface

for the polar rose , what type of formula used you?

the iso surface or parametric?

By usual way ,on web it's parametric ?

on this forum

http://k3dsurf.s4.bizhat.com/viewtopic.php?t=108&postdays=0&postorder=asc&start=75

abdelhamid belaid explain how make round a sinus curved , but it's iso formula .

cheers

denisc
Back to top View user's profile Send private message Send e-mail
denisc



Joined: 24 Apr 2013
Posts: 92

PostPosted: Tue Oct 15, 2013 12:09 am    Post subject: Reply with quote

hello uoface

For the moment, i am not a solution for more reasons.

When you try make tube with spiral, you are not intersection of segments.


When you try make tube with parametric formula in general

; When you are intersections of segments, the tube is not perfect.

With knoten torus perfect.





With treefold torus , i cannot round the model prefectly, for the moment



with lissajous , is a best



you can make a tube , but not all round when you try to flat him .




with of polar rose , i am a bubon of 6 part but not center

for n=3/2

it's a full model.




(I was looking for this for some time, so it is)

i try to model a TRIFOLIUM with isometric formula + the solution of

abdelhamid belaid.

dont work for this formula

(x^2+y^2)^2-x*(x^2-3*y^2)

in final

((y-((x^2+y^2)^2-x*(x^2-3*y^2)))*cos(atan((4*x+3)*y^2+4*x^3-

3*x^2)) )^2 +z^2-0.01

perhaps , it's a mistake?


a general formula exist for tube in a nb for mathematica, but my link is

dead and it's in french .

cheers


denisc
Back to top View user's profile Send private message Send e-mail
denisc



Joined: 24 Apr 2013
Posts: 92

PostPosted: Tue Oct 15, 2013 12:31 pm    Post subject: Reply with quote

hello uoface

here a view of quadrifolium .

it's possible on parametric , but is complicated a lot , because you must

calculed the formula of tube for each figure.

ex/ for trifolium and quadrifolium you are two different formule for the tube.



And I'm not as good as others for this.

cheers

ps:
(if you have enough of it you can use hexagon, ( It's free and there is a function to magnify the line.)

I am also well aware that this was not the initial request, but I hoped this helped a little anyway.


denisc
Back to top View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    K3DSurf forum Forum Index -> Mathematical Models Collection All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


2005 Powered by phpBB © 2001, 2005 phpBB Group


Start Your Own Video Sharing Site

Free Web Hosting | Free Forum Hosting | FlashWebHost.com | Image Hosting | Photo Gallery | FreeMarriage.com

Powered by PhpBBweb.com, setup your forum now!
For Support, visit Forums.BizHat.com