Mandlebrot (w/ zoom)

[TheOneTrueGod]

I searched around, and I found an old post on this as well, but I decided to create this anyway, as the old version didn't have zooming capabilities (as far as in-program went, anyway)

Warning: Turing cannot handle anything zoomed in too far. The window might start going kinda funky, and unexpected behaviour may develop.

code:

const maxdepth := 50 %Change this if you plan on zooming in farther than, say, 3 medium zooms.  The picture will become clearer, %but take longer to load. var left : real := -2 var right : real := 2 var bottom : real := -2 var top : real := 2 type CoOrd :     record         a, b : real     end record function SquareIt (z : CoOrd) : CoOrd     var z2 : CoOrd     z2.a := 2 * z.a * z.b     z2.b := z.b ** 2 - z.a ** 2     result z2 end SquareIt function AddIt (z, z3 : CoOrd) : CoOrd     var z2 : CoOrd     z2.a := z.a + z3.a     z2.b := z.b + z3.b     result z2 end AddIt function FindColour (z : CoOrd) : int     var z2 : CoOrd := z     for i : 0 .. maxdepth         z2 := SquareIt (z2)         z2 := AddIt (z2, z)         if sqrt (z2.a ** 2 + z2.b ** 2) > 2 then             result i         end if     end for     result maxdepth end FindColour var z : CoOrd var mx, my, button : int var mandlepic : int var newleft, newright, newtop, newbottom : real loop     View.Set ('nooffscreenonly')     for j : 0 .. maxy         for i : 0 .. maxx             z.a := (top - bottom) * j / maxy + bottom             z.b := (right - left) * i / maxx + left             drawdot (i, j, round (FindColour (z) / maxdepth * 254) + 1)         end for     end for     View.Set ('offscreenonly')     mandlepic := Pic.New (0, 0, maxx, maxy)     loop         mousewhere (mx, my, button)         if button = 1 then             newleft := mx             newbottom := my             loop                 mousewhere (mx, my, button)                 Pic.Draw (mandlepic, 0, 0, picCopy)                 drawbox (round (newleft), round (newbottom), mx, my, brightblue)                 View.Update                 cls                 exit when button = 0             end loop             exit when mx > newleft and my > newbottom         end if     end loop     Pic.Free (mandlepic)     newtop := (top - bottom) * my / maxy + bottom     newbottom := (top - bottom) * newbottom / maxy + bottom     newright := (right - left) * mx / maxx + left     newleft := (right - left) * newleft / maxx + left     left := newleft     right := newright     bottom := newbottom     top := newtop end loop

[Clayton]

looks good, but i dont quite understand what you mean by "zoom", all i can do is draw a box and nothing happens, is that supposed to happen?(thats what it looks like from the code, but i cant be sure...) gj otherwise

[TheOneTrueGod]

you have to draw the box from bottom left to top right, or else it won't work:
|----------------finish
| |
| |
| |
start ------------|

[Clayton]

ok i got it now, very cool, although that thing with the box not being able to be drawn top to bottom... not good, you need to make it so that you can draw the box any way and end up with the same result, gj otherwise, i understand what youve typed, but i never would have been able to come up with that on my own, gj

[codemage]

It wouldn't take much to fix that bug. Just check which of the y-click coordinates are lower, which of your x-click coords are leftmost, etc...