function?christmas


%?Anselm?Ivanovas?anselm.ivanovas@student.unisg.ch




%%?setup
snow=450;????%?number?of?snow?flakes?[0?..?5000]


%%?draw?tree
h=0:0.2:25;?%vertical?grid
[XYZ]?=?cylinder（tree（h））;?%produce?a?tree?formed?cylinder
Z=Z*25;?%scale?to?the?right?heigth



treeDiffusion=rand（12621）-0.5;%some?horizontal?diffusion?data


for?cnt1=1:21
???
????for?cnt2=16:126%starting?above?the?trunk
???????%get?the?angle?to?always?diffuse?in?direction?of?the?radius
???????angle=atan（Y（cnt2cnt1）/X（cnt2cnt1））;
???????%split?the?diffusion?in?the?two?coordinates?depending?on?the?angle
???????X（cnt2cnt1）=X（cnt2cnt1）+cos（angle）*treeDiffusion（cnt2cnt1）;
???????Y（cnt2cnt1）=Y（cnt2cnt1）+sin（angle）*treeDiffusion（cnt2cnt1）;
???????%some?Vertical?diffusion?for?each?point
???????Z（cnt2cnt1）=Z（cnt2cnt1）+（rand-0.5）*0.5;
????end
???
end
%draw?the?tree
h0??=?figure（‘Units‘‘inches‘）;
pos?=?h0.Position;
pos（1）?=?1;?pos（2）?=?1;
pos（3）?=?7;?pos（4）?=?7;
h0.Position?=?pos;
surfl（XYZ‘light‘）

%Use?as?nice?green?color?map?（darker?at?the?bottom?lighter?at?the?top）
r=（0.0430:（0.2061/50）:0.2491）‘;%red?component
g=（0.2969:（0.4012/50）:0.6981）‘;%green?component
b=（0.0625:（0.2696/50）:0.3321）‘;%blue?component
map=[rgb];%join?in?a?map
for?cnt=1:6
????%change?the?lower?part?to?brown?for?the?trunk
????map（cnt:）=[77635]/265;
end
colormap（map）%set?the?map
view（[-37.54]）%Change?the?view?to?see?a?little?more?of?the?Actual?3D?tree
lighting?phong?%some?nice?lighting
shading?interp?%remove?grid?and?smoothen?the?surface?color
axis?equal?%takes?care?of?display?in?the?right?proportion
axis（[-10?10?-10?10?0?30]）?%give?some?more?axis?space?（for?the?snow?later）
axis?off?%but?don‘t?show?axis
hold?on?%to?draw?the?rest
title（‘Merry?Christmas?劉成祥‘‘color‘‘w‘...
????‘fontsize‘25...
????‘fontweight‘‘Bold‘）


set（gcf‘color‘[22?32?51]./255）
%%?Presents
%Draw?some?presents?around?the?tree?（each?with?random?color）
drawPresent（2-40332）;
drawPresent（-430231.5）;
drawPresent（530433）;
drawPresent（-14-50631）;
drawPresent（-9-100222）;
drawPresent（040433）;
drawPresent（-6-130333）;
%%?Snow

%create?some?random?3D?coordinates?for?the?snow?（amount?as?in?setup?above）
snowX=（rand（snow1）*25-12.5）;
snowY=（rand（snow1）*25-12.5）;
snowZ=（rand（snow1）*27）;
color0?=?jet（length（snowX））;
%Note:Some?flakes?will?end?up?IN?the?tree?but?just?can‘t?be?seen?then
for?ii?=?1:length（snowX）
????plot3（snowX（ii）snowY（ii）snowZ（ii）‘*‘‘col