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   double theta,phi,phi2;
   int i,i2,j;
   BITMAP *imagein,*imageout;

   Form the input and output image arrays
   Read an input image from a file

   for (j=0;j<image.height;j++) {
       
      theta = PI * (j - (image.height-1)/2.0) / (double)(image.height-1);
      
      for (i=0;i<image.width;i++) {
          
         phi  = TWOPI * (i - image.width/2.0) / (double)image.width;
         
         phi2 = phi * cos(theta);
         
         i2  = phi2 * image.width / TWOPI + image.width/2;
         
         if (i2 < 0 || i2 > image.width-1) {
            newpixel = red;                         /* Should not happen */
         } else {
            newpixel = imagein[j*image.width+i2];
         }
         imageout[j*image.width+i] = image.newpixel;
      }
   }

sync on : sync rate 60 : autocam off
set window off
set display mode 1024,768,32

noise set params 0, 0.75, 0.02, 1.25, 8, 1

`img1 = create_perlin_texture(512,512)
`img2 = spherise_texture(img1)
imgs = create_perlin_sphere(256)

obj1 = find free object()
make object sphere obj1,100,32,32
texture object obj1,imgs

position camera 0,90,-90 : point camera 0,0,0

do
    yrotate object obj1,object angle y(obj1)+0.5
    `paste image img1,0,0
    `paste image img2,0,256
    paste image imgs,0,0
    draw_cos()
    sync
loop

end

function create_perlin_texture(wid,hgt)
    bm = find free bitmap()
    create bitmap bm,wid,hgt
    noise set params 0, 0.75, 0.1, 1.25, 8, 0
    lock pixels
    for x=0 to wid-1
        for y=0 to hgt-1
            c = ( ( noise get height tiled (0,x,y,wid,hgt) + 1.0 ) / 2.0 ) * 255.0
            if c<0 then c=0
            if c>255 then c=255
            c=c+(c<<8)+(c<<16)
            dot x,y,c
        next
    next
    unlock pixels
    img = find free image()
    get image img,0,0,wid,hgt
    delete bitmap bm
endfunction img

function spherise_texture(img1)
    wid = image width(img1)
    hgt = image height(img1)
    widh = wid/2
    bm = find free bitmap()
    create bitmap bm,wid*2,hgt
    paste image img1,wid,0
    lock pixels
    cent = wid + widh
    for y=0 to hgt-1
        m# = widh / sin(180.0/hgt*y)
        p# = widh / m#
        for x=0 to widh
            a# = p# * x
            c=point( cent - a# , y )
            dot widh - x , y, c
            c=point( cent + a# , y )
            dot widh + x , y, c
        next
    next
    unlock pixels
    img2 = find free image()
    get image img2,0,0,wid-1,hgt-1
    delete bitmap bm
endfunction img2

function create_perlin_sphere_old(size)
    bm = find free bitmap() : create bitmap bm, size, size
    sizeh = size / 2
    lock pixels
    for y = 0 to size
        m# = sizeh / sin( 180.0 / size * y )
        m# = sizeh / m#
        for x=0 to sizeh
            a# = m# * x
            v# = noise get height tiled(0, sizeh - 1 - a#, y, size, size) : v# = 1.0 + ( v# / 2.0 ) * 255.0 : c = v#
            if c<128 then c=rgb(c,c,128) else c=rgb(c,c,c)
            dot sizeh-1-x,y,c
            v# = noise get height tiled(0, sizeh + a#, y, size, size) : v# = 1.0 + ( v# / 2.0 ) * 255.0 : c = v#
            if c<128 then c=rgb(c,c,128) else c=rgb(c,c,c)
            dot sizeh+x,y,c
        next
    next y
    unlock pixels
    img = find free image() : get image img,0,0,size-1,size-1 : delete bitmap bm
endfunction img

function create_perlin_sphere(size)
    bm = find free bitmap() : create bitmap bm, size, size
    PI#=3.14136592 : TWOPI# = 2 * PI# : s#=size
    lock pixels
    for j=0 to size-1
        `theta# = PI * (j - (size-1)/2.0) / (float)(size-1)
        theta#=PI# * (j - (s#-1) / 2.0) / (s#-1)
        
        for i=0 to size-1
            phi#=TWOPI# * (i - s#/2.0) / s#
            
            phi2#=phi#*cos(theta#*180.0/PI#)
            
            i2# = phi2# * s# / TWOPI# + (s#/2.0) : i2=i2#
            
            h#=noise get height tiled(0,i2,j,size,size)
            h#=h# * 255.0
            c=h#
            if c<0 then c=rgb(abs(c),abs(c),255) else c=rgb(255,255-c,255-c)
            dot i,j,c
        next
    next
    unlock pixels
    img = find free image() : get image img,0,0,size-1,size-1 : delete bitmap bm
endfunction img

function draw_cos()
    for y=0 to 255
        dot 127.5+sin(180.0/256.0*y)*127.5,y,0xffffff
    next
endfunction