From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Original-To: caml-list@yquem.inria.fr Delivered-To: caml-list@yquem.inria.fr Received: from mail1-relais-roc.national.inria.fr (mail1-relais-roc.national.inria.fr [192.134.164.82]) by yquem.inria.fr (Postfix) with ESMTP id 594E7BBAF for ; Tue, 9 Nov 2010 12:02:11 +0100 (CET) X-IronPort-AV: E=Sophos;i="4.59,174,1288566000"; d="scan'208";a="86587933" Received: from yquem.inria.fr ([128.93.8.37]) by mail1-relais-roc.national.inria.fr with ESMTP; 09 Nov 2010 12:02:11 +0100 Received: by yquem.inria.fr (Postfix, from userid 25991) id 42700BBAF; Tue, 9 Nov 2010 12:02:11 +0100 (CET) Date: Tue, 9 Nov 2010 12:02:11 +0100 From: Daniel de Rauglaudre To: caml-list@inria.fr Subject: Re: [Caml-list] MLbrot: Mandelbrot Set in OCaml Message-ID: <20101109110211.GA32550@yquem.inria.fr> References: <20101108150313.GA11054@yquem.inria.fr> <698193382.354372.1289232453372.JavaMail.root@zmbs3.inria.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <698193382.354372.1289232453372.JavaMail.root@zmbs3.inria.fr> User-Agent: Mutt/1.5.9i X-Spam: no; 0.00; rauglaudre:01 rauglaudre:01 ocaml:01 0100,:01 recenter:01 'x':01 'x':01 iteration:01 iterated:01 iteration:01 ocaml:01 gtk:01 homeip:01 zoom:98 zoom:98 Hi, On Mon, Nov 08, 2010 at 05:07:33PM +0100, Goswin von Brederlow wrote: > Only looked at the pictures so far but they do look good. I'm missing > some screenshots though. How does the interface look like? I assume you > have some way to select a part of the image to zoom? When clicking with left button, you zoom (twice) centered to that point. Middle button: recenter. Right button: unzoom. And the keys 'z' and 'x' zoom and unzoom, 'Z' and 'X' do it 10 times. > It would also be nice to know a bit more about what drawing methods you > support. Do you just compute every pixel or do you support guessing, > boundary trace, tesseracting? I compute every pixel. I searched on the Internet for faster algorithms but I did not find. What are guessing, boundary trace and tesseracting ? Well, I am going to google these terms :-) > Also do you have a coloring mode using distance estimation? > E.g. color all points < 0.5 pixels distance from the M-Set white. No. I see that I have many things to learn... :-) > Can you zoom and refine the image like xaos does? I did not know xaos, so I installed it, and tested it a little. Well, it is very fast indeed! Yes, I refine the image (you mean around Mandelbrot islands ?) by extending the number of iterations some times. > Do you support the single orbital iteration method? That puts a 3x3 > points grid over the image plus 4 control points. Points of the image > are aproximated from the 9 grid points. The 13 points are iterated a few > iterations as long as the 4 reference points are close to approximating > the same points. If the error becomes to great you go back an iteration, > subdivide the grid into 4 parts, approximate the missing point and > repeat for each subgrid. Esspecially on dep zooms this can speed up > calculations by magnitudes since the first few thousand iterations of > each point will be done by calculating only 14 points and approximating. Oops, I have to read that again, that seems interesting but at the first reading, I don't understand everything. > You say you are using OpenGL, so where are the 3D images? History: I was just looking for a graphic toolkit instead of mine (olibrt, which is old and works only on X Window). Many people here (Inria) use OpenGL, to indeed doing 3D, so I tested, but only in 2D. Well, actually, I tested it on a mini-small-tiny-mplayer I wrote in OCaml: OpenGL is interesting because of Direct Rendering which accelerate the displaying. So, I tested OpenGL in Mlbrot, after having separated the graphic toolkit from the rest of the program. Perhaps, that makes it work under Mac and Windows? I don't know. And a few days ago, I tested with Gtk, which appears to be the good solution and I continue programming with it. Perhaps I try out the 3D feature of the Mandelbrot Set one day. I just looked at a couple of sites talkint about it. > I've converted some 20 year old code into ocaml a while back that > generates 3D images. Putting the height map into OpenGL and render it > through that would probably improve the quality: > http://mrvn.homeip.net/mandelbrot/ Interesting, but I would prefer something more 3D, like cauliflowers. Thank you for your message! -- Daniel de Rauglaudre http://pauillac.inria.fr/~ddr/