Comments on: On the heels of Google IO – playing with HTML5 and F# web services

By: pete

pete — Fri, 30 Jul 2010 19:55:59 +0000

both are wrong…I havent tried this, but looking at the Fibonacci values, I need to start furthur up the sequence as the lower values are not exactly the same (3/5 = .6, 8/5 = .615, 89/144=.618).
Thanks.

By: alex p

alex p — Thu, 29 Jul 2010 21:52:57 +0000

so what’s wrong then – the tile sizes, or their locations? you might get rounding errors in arcX/arcY – i think those will be integers based on how your code is written.

By: pete

pete — Wed, 28 Jul 2010 15:23:47 +0000

Thanks for the reply.
I’m not actually plotting the values on screen yet. I’m only drawing the tiles out by hand so see if my conversion is correct. The values will be plotted on a WPF canvas and I’m still searching for the correct method to do that. (Arcsegement seems to be a possiblity but it doesnt use degrees or radians.) The JS to C# conversion was not an issue except I wasnt exactly sure I got the drawFactor right or possibly some other rounding issue.

By: alex p

alex p — Wed, 28 Jul 2010 06:36:25 +0000

what do you mean your numbers are wrong? the tilings? assuming you just copied the source (no reason not to – basic js should be the same as c#), then the only thing i can think of is maybe it’s expecting degrees instead of radians?

By: pkz

pkz — Wed, 28 Jul 2010 06:19:57 +0000

Trying to convert this to C#, but my numbers arent quite right:
//
var x = canvas.ActualWidth / 2;
var y = canvas.ActualHeight / 2;
var arcX = x;
var arcY = y;

// just hard code them
int[] FibonacciValues = {0,1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233};

var drawFactor = Math.Min(canvas.ActualWidth, canvas.ActualHeight) / (2 * (FibonacciValues[FibonacciValues.Length -1])) + 1;

for (var i = 1; i < FibonacciValues.Length; i++)
{

var last = FibonacciValues[i - 1];
var current = FibonacciValues[i];

var num = current * drawFactor;
var lastNum = last * drawFactor;
var idx = i – 2;

var startAngle = 0.0;
var endAngle = 0.0;
switch (idx % 4)
{
case 0:
x += lastNum;
y += lastNum – num;
arcX = x;
arcY = y;
startAngle = Math.PI / 2;
endAngle = Math.PI * 2;
break;
case 1:
x -= num – lastNum;
y -= num;
arcX = x;
arcY = y + num;
startAngle = Math.PI * 2;
endAngle = Math.PI * 3 / 2;
break;
case 2:
x -= num;
arcX = x + num;
arcY = y + num;
startAngle = Math.PI * 3 / 2;
endAngle = Math.PI;
break;
case 3:
y += lastNum;
arcX = x + num;
arcY = y;
startAngle = Math.PI;
endAngle = Math.PI / 2;
break;
}

if (idx < 0)
continue;

}

any idea of where I went wrong?