Directionally Challenged

[Fractal Ken]

Fractal generated by homemade software. It was colored by selecting pixels from an input image: a plasma cloud rendered and edited in GIMP. I also used GIMP for post-processing.

[Kali]

Really nice! How are the colors selected from the image? (I mean the algorithm)

[Fractal Ken]

Thanks, Kali! The algorithm varies from case to case, but I can describe the approach broadly by comparing it to the more usual method.

STANDARD COLORING

The program has a way of determining directly the amount the red, green, and blue for each pixel of the output image. That is, based on results from iterative calculations for a particular pixel, it computes

   red = . . .        on a scale of 0 to 255
   green = . . .      on a scale of 0 to 255
   blue = . . .       on a scale of 0 to 255

IMAGE-BASED COLORING

Assume the input bitmap image has NROW rows and NCOL columns. The software makes use of similar formulas

   row_number = . . .     on a scale of 1 to NROW
   col_number = . . .     on a scale of 1 to NCOL

Iterative fractal calculations are performed for a particular output pixel. Based on the results, the program then evaluates these two formulas. To color the pixel of the output image, it just grabs the red/green/blue values from the pixel of the input image located at the computed row_number and col_number.

Clear as mud, I'm sure.

Regards,
Ken

[Kali]

Thanks for the info. I'm surely will be doing something like this, the results are really cool. I wonder if it can be done in Ultrafractal.
Anyway, I'll be coding a self-made fractal generator soon... I think you were right when you wrote in one post a time ago, that making fractal art with a self-made program gives you more satisfaction than using somebody else software. It also opens the possibilities of full customization.
I don't know if I'll be going to code it in VB.NET, or maybe C#. I'm a VB programmer, but I was teaching myself C# lately, and I'm getting it fast.
But surely not Fortran... That's your speciality 

[Fractal Ken]

Anyway, I'll be coding a self-made fractal generator soon...

Great! And don't worry about your real life. Writing the software won't be at all time consuming. 

But surely not Fortran...

Wise choice.