Stepped Shamrock

on 14 Oct 2022

% Shamrock

% Compute ideal # of vertices so we get sharp points

%nb = 3; % number of bumps

%vpb = 100; % vertices per bump. Odd makes tops flat, even sharp

%n = nb*vpb+1; % total number of vertices. +1 for last vertex matching the first.

t=linspace(0,2*pi,301)*3;% linspace(0,2*pi,n)*nb;

% Mesh

r=linspace(0,1,6);

[R,T]=ndgrid(r,t);

% Unit Wave function

M=(1-mod(T*3,2*pi)/pi);

W = rescale(1-(abs(M)-1/3).^2,.2,1);

% Apply wave to R

S=R.*W;

% Vertices for a disk with wave applied

X=S.*cos(T);

Y=S.*sin(T);

surf(X,Y,X*0,R,FaceC='i',EdgeC='n');

% Re-use r from the 'radius' computation to create a green colormap.

m(2,:)=r;

m(3,:)=0;

colormap(gca,m');

axis equal off

view(2)

Open in MATLAB Online