Xojo Developer Conference
25/27th April 2018 in Denver.
MBS Xojo Conference
6/7th September 2018 in Munich, Germany.

Platforms to show: All Mac Windows Linux Cross-Platform

FAQ.How to compare two pictures?
Answer: You can try this code:
Example:
```Function ComparePictures(p as picture,q as picture) as Integer  dim r,u as RGBSurface  dim x,y,n,m,h,w as Integer  dim w1,w2,h1,h2,d1,d2 as Integer  dim c1,c2 as color    h1=p.Height  h2=q.Height  w1=p.Width  w2=q.Width  d1=p.Depth  d2=q.Depth    if d1<>d2 then    Return 1  elseif w1<>w2 then    return 2  elseif h1<>h2 then    Return 3  else    r=p.RGBSurface    u=q.RGBSurface        if r=nil or u=nil then      Return -1    else      h=h1-1      w=w1-1      m=min(w,h)            for n=0 to m        c1=r.Pixel(n,n)        c2=u.Pixel(n,n)        if c1<>c2 then          Return 4        end if      next            for y=0 to h        for x=0 to w          c1=r.Pixel(x,y)          c2=u.Pixel(x,y)          if c1<>c2 then            Return 5          end if        next      next            // 0 for equal      // -1 for error (no RGBsurface)      // 1 for different depth      // 2 for different width      // 3 for different height      // 4 for different pixels (fast test)      // 5 for different pixels (slow test)    end if  end if    Exception  Return -1End Function
```
Notes: Remember that this only works on bitmap pictures, so the picture.BitmapMBS function may be useful.