close all ; 

clear all ; 

clc; 

%%author - Praga

%%process time - 13 sec (without thresholding) 

%%             - 1 minute (with thresolding)

%%%%%%%%  Task 1  %%%%%%%%%%%%%%%%%%%%%%%

%%the conditions for R %%%%%%%%%%%%%%%%%%

%% 1) tan(theta/2) > R/Yp

%% 2) Yus*cos(theta/2) > 2R

%% 3) Xus*cos(theta/2) > 2R

%% 4) Yus - Yp > R

%% 5) Xus > 2R

%%

%%%%%%% Task 2 %%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%defining all the variables%%%%%%%%

FOV=120;             %degree

theta=(pi*2)/180;    %radian 

R=2;                 %cm

Yp=6;                %cm

Xus=10;              %cm

Yus=10;              %cm

Sx=0.1;              %cm

Sy=0.1;              %cm

num_pixel=Xus/Sx;  %done only for X as both are equal

%%to get the main image over here

[im_main]=createmainimage(Xus,R,theta,num_pixel);

%%%%%%%%% Task 3 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%creation and visualization of the empty voxel%%%

VoxelMat=zeros(num_pixel,num_pixel,num_pixel);

for i=1:num_pixel

    for j=1:num_pixel

        for k=1:num_pixel

            if (i-num_pixel/2)^2+(j-num_pixel/2)^2+(k-num_pixel/2)^2<(R/Sx)^2

                VoxelMat(i,j,k)=255;

            end

        end

    end

end

%view of voxels

[vol_handle,FV]=VoxelPlotter(VoxelMat,1); 

view(3);

daspect([1,1,1]);

set(gca,'xlim',[0 num_pixel], 'ylim',[0 num_pixel], 'zlim',[0 num_pixel]);

title('actual sphere in Voxels without the reconstruction algorithem');

%push of taken image back into a 3D array as reconstruction 

%reconstruction view will be differnt as it makes coding easy

%rotating the reconstructed matrix by 90 degrees will give the original

%will be working with X and Z axis 

%%nearest neighbour voxel mapping

array_recon=zeros(num_pixel,num_pixel,num_pixel);

angle_1=-pi/3:theta:pi/3; %in radians

%special case handled first .......

%array_recon(:,:,num_pixel/2)=im_main(:,:,31);

%delete the angle zero from array 

%angle_1= angle_1([1:30, 32:end]);

for k=1:size(angle_1,2)

    %rotation matrix with respect to y axis 

    %Rot = [cos(angle(k)) 0 sin(angle(k));0 1 0;-sin(angle(k)) 0 cos(angle(k))];

    x=size(im_main,1);

    y=size(im_main,2);

    for i =1:1:x

        for j=1:1:y

            new_cord=rotx(angle_1(k)*180/pi)*[i,j,0]';

            new_cord(3)=new_cord(3)+50;

            new_cord=ceil(new_cord);

            if new_cord(3)>0

                array_recon(new_cord(1),new_cord(2),new_cord(3))=im_main(i,j,k);

                array_recon=uint8(array_recon);

            end

        end

    end    

end

%%print voxel after nearest neighbour map

figure;

[array_recon_1]=VoxelPlotter(array_recon,1); 

view(3);

daspect([1,1,1]);

set(gca,'xlim',[0 num_pixel], 'ylim',[0 num_pixel], 'zlim',[0 num_pixel]);

title('Voxels without the interpolation');

%%%%%bilinear interpolation %%%%%%%%%%%%

zoomed=zeros(size(array_recon));

%%%bilinear interpolation  

for j=1:size(array_recon,3)

    zoomed(:,:,j)=bilinear( array_recon(:,:,j) );

end

figure;

[zoomed_1]=VoxelPlotter(zoomed,1); 

view(3);

daspect([1,1,1]);

set(gca,'xlim',[0 num_pixel], 'ylim',[0 num_pixel], 'zlim',[0 num_pixel]);

title('Voxels after bilinear interpolation');

mkdir('imagesafterrecon');

cd('imagesafterrecon');

%save the image

filename = 'p%d.bmp';

filename = sprintf(filename,image_index);

image_index = image_index + 1;

imwrite(im,filename);