Comments for James Henstridge

Comment on NBN talk at PLUG by James Henstridge

James Henstridge — Mon, 19 Mar 2012 07:14:28 +0000

@Raphael: as mentioned in the post, it is GPON.

Comment on NBN talk at PLUG by Raphael

Raphael — Mon, 19 Mar 2012 07:00:44 +0000

What sort of technology is used on the optical side ? *pon, ethernet …?

Comment on Javascript Mandelbrot Set Fractal Renderer by alex_mass

alex_mass — Tue, 17 May 2011 12:23:37 +0000

Hi James,

thanks for the post
I slightly derived your code to try to make it more “education ready”.

http://www.framexpeditions.com/~alex2/teaching/mandelbrot/

Alex

Comment on Javascript Mandelbrot Set Fractal Renderer by Jake

Jake — Sat, 07 May 2011 18:36:43 +0000

Hi James,

I now have learned enough about Canvas to re-do my Mandelbrot generator using it. It is much faster, and I’m pleased with the result. I don’t know about web workers (I’m only a maths teacher), maybe that’s the next step. In case you want to try my Mandelbrot, here it is: http://www.jakebakermaths.org.uk/maths/mandelbrot/canvasmandelbrotv12.html. It works on Chrome, Firefox and IE9; I don’t know about Safari or Opera.

Jake.

Comment on Javascript Mandelbrot Set Fractal Renderer by Jake

Jake — Thu, 28 Apr 2011 07:17:03 +0000

Thanks James and Eric for your comments, it’s helpful to understand some of these speed issues. I’ll get working on learning canvas.

Jake

Comment on Javascript Mandelbrot Set Fractal Renderer by James Henstridge

James Henstridge — Thu, 28 Apr 2011 03:37:38 +0000

@Jake: I’d imagine the SVG method would be a fair bit slower and more memory hungry, since you’re asking the browser to create a DOM node for each pixel in the image, while with the canvas I just need to update the RGB image data associated with the single canvas element. You could still apply web workers to parallelise the calculation in your implementation.

While there are areas that are obviously lacking detail due to the iteration limit I set, there are other areas of the image where I hit the floating point precision limit first and the image becomes blocky. I imagine you could find areas in your version that exhibit this.

Comment on Javascript Mandelbrot Set Fractal Renderer by Eric Freeman

Eric Freeman — Thu, 28 Apr 2011 03:17:14 +0000

Jake, canvas is now widely supported by pretty much all modern browsers.

Eric

Comment on Javascript Mandelbrot Set Fractal Renderer by Eric Freeman

Eric Freeman — Thu, 28 Apr 2011 03:16:29 +0000

James can you contact me directly? I have a question for you (about publishing some of your code).

Thanks,

Eric

Comment on Javascript Mandelbrot Set Fractal Renderer by Jake

Jake — Fri, 22 Apr 2011 19:37:28 +0000

Hi, I really like your mandelbrot. I’ve done one recently in javascript in xhtml with svg, which works on Chrome and IE9 but is too intensive for Firefox. Mine is slower than yours. I haven’t learnt ‘canvas’ but you’ve got great results with it. For some reason I was getting the impression that canvas wasn’t supported by many browsers, but on my computer your version works fine on Chrome and FF. I didn’t use multiple precision arithmetic either, because I think the limits are imposed more by the iteration max (I used 2000, I think you used 1024), and the consequent calculation speeds, than the depth of zoom. Jake.

Comment on Javascript Mandelbrot Set Fractal Renderer by Eric Freeman

Eric Freeman — Wed, 20 Apr 2011 04:19:55 +0000

Looks great, and nice code. With safari I’m maxing out 8 cores. Nice.

Eric