how to take picture of a virtual cube in matlab? i have generated the cube but do not know how to take picture in matlab

i have generated a virtual 3D cube. i am asked to take a picture of this cube from 4 meters away and with a tilt angle of 30 degree. do i have to do this with rotation matrix R and translation matrix T? this is the code of the virtual 3D cube

%%Generate 3D calibration pattern: 
%%Pw holds 32 points on two surfaces (Xw = 1 and Yw = 1) of a cube 
%%Values are measured in meters.
%%There are 4x4 uniformly distributed points on each surface.

cnt = 1;

%%plane : Xw = 1
Pw = zeros(4,3);%preallocating Pw

for i=0.2:0.2:0.8,%it means it starts from 0.2 gives an interval 0.2 and goes till 0.8
 for j=0.2:0.2:0.8,
   Pw(cnt,:) = [1 i j];%is the cnt-th row of pw , pw is a matrix whos cnt-th row is a row matrix, cnt is a variable that starts from 1 and after forming 
   %the row matrix, it goes on till i and j conditions are fulfilled. 
   cnt = cnt + 1;

   end
  end

%%plane : Yw = 1

for i=0.2:0.2:0.8,
 for j=0.2:0.2:0.8,
   Pw(cnt,:) = [i 1 j];
   cnt = cnt + 1;
 end
end

N = cnt;

%%plot3(Pw(:,1), Pw(:,2), Pw(:,3), '+');

%%Virtual camera model 

   %%Extrinsic parameters : R = RaRbRr

gamma = 40.0*pi/180.0;
Rr = [ [cos(gamma) -sin(gamma) 0];
       [sin(gamma) cos(gamma)  0];
       [  0          0         1]; ];

beta = 0.0*pi/180.0;

Rb = [ [cos(beta) 0 -sin(beta)];
       [0         1       0];
       [sin(beta) 0  cos(beta)]; ];

alpha = -120.0*pi/180.0;
Ra = [ [1      0                0];
       [0   cos(alpha)  -sin(alpha)];
       [0   sin(alpha)   cos(alpha)]; ];

R = Ra*Rb*Rr;

T = [0 0 4]';

%%Intrinsic parameters

f = 0.016;
Ox = 256;
Oy = 256;

Sx = 0.0088/512.0;
Sy = 0.0066/512.0;

Fx = f/Sx;
Fy = f/Sy;

%%asr is the aspect ratio
asr = Fx/Fy;

%%Generate Image coordinates

%%surface Xw = 1
cnt = 1;
Pc = zeros(16,3);
n=length([(Ox - Fx*Pc(cnt,1)/Pc(cnt,3)) (Oy - Fy*Pc(cnt,2)/Pc(cnt,3))]);
 p=zeros(16,n);

for cnt = 1:1:16,
   Pc(cnt,:) = (R*Pw(cnt,:)' + T)';
   p(cnt,:)  = [(Ox - Fx*Pc(cnt,1)/Pc(cnt,3)) (Oy - Fy*Pc(cnt,2)/Pc(cnt,3))];
end
plot(p(:,1), p(:,2), 'r+');
axis([0 512 0 512]);
grid;
hold;

%%surface Yw = 1
for cnt = 17:1:32,
   Pc(cnt,:) = (R*Pw(cnt,:)' + T)';
   p(cnt,:)  = [(Ox - Fx*Pc(cnt,1)/Pc(cnt,3)) (Oy - Fy*Pc(cnt,2)/Pc(cnt,3))];
end
plot(p(17:32,1), p(17:32,2), 'g+');
%%plot3(Pc(:,1), Pc(:,2), Pc(:,3), '+');
grid;

please let me know. i can understand that i need to do a little modification in this code, but i don't understand how to take a picture of this virtual cube.

Answer 1

[Walter Roberson]

You can use getframe() to take an image. You can also use saveas() or print() if you want an image file (e.g., .jpg)

[Sat m]

thank you. but can you please tell me how can i take picture of this virtual cube from 4 meters distance and from a tilt angle 30 degree? can i do this with getframe()? if you give me some code it will be good for me.

[Walter Roberson]

http://www.mathworks.com/help/matlab/visualize/view-overview.html