Holidays2013

looking at 2weeks free time over the holidays this is where I hope to put some of my "reaserch" and toy samples

Mandelbrot

I had a look around Hackage searching for a suitable library to help me generate pictures (I want come back and try to write a medicore raytracer in Haskell as advanced project) and JuicyPixels seemd just fine (I kindof liked the easieness of generateImage)- so thank you Vincent for your great work!

Of course I need something to toy with and I always loved to write yet another mandelbrot-set drawing app ... so here we go!

Right now this will only produce a complete image of the well-known set - no zoom or anything. Like this:

I modified the algorithm to test the Repa package - that is I tried to compute the images pixel-array in parallel. So far the speedupt is not that great and I guess I have to really think this through a bit more.

fiddling with threepenny-gui

After some timeout I decided to play a bit more with this mandelbrot-generator by trying to implement it using threepenny-gui.

As of now this works ... well ok - it's not very fast or very beautiful (just shows the image and some very basic "wait"-text).

I am not sure I really got the libraries spirit right but it was kindof fun (really nasty hacking and head-scratching, till I got it).

To get this running you have to run the executable and then go with your favorite browser to localhost:10000. It will take a while to create the starting image and after this is done you can click on a point on the image to zoom into that region (rinse and repeat / enjoy).

obvious-stupid-mistakes I made

Yes this is embarassing, but here are the most-stupid:

• toyed with JuicyPixels and imported PixelRGB8 but forgot the constructors (PixelRGB8(..)) and then being dumbfolded for several minutes by the obvious error:

  Not in scope: data constructor `PixelRGB8'

• tried to implement a widget into Threepenny-GUI to show my image and really fried my head how I could to some kind of accumulation to translate the clicks into new views (you see: i need the old-view to know "where" I clicked) ... the solution I found was to create a "mapper"-function between views for a click (at the image-coordinates) and then use this together with accumulateB interesting concept but a bit counterintuitive for me but logical in the end ... really love Haskell - always something new to figure out.