[PD] Graph a circle arc in an array?

Tyler Leavitt thecryoflove at gmail.com
Sun Apr 10 16:14:11 CEST 2011


Ok well now I have really attached the patch...

On Sun, Apr 10, 2011 at 7:12 AM, Tyler Leavitt <thecryoflove at gmail.com>wrote:

> I've not had any real success using the formulas with [sin] and [cos]...
> maybe I'm missing something here. The only solution that I've gotten to work
> is the midpoint circle algorithm with Peter's patch.
>
> I've included a patch to show where I'm struggling... When the arc gets
> drawn with bigger radiuses (and bigger arrays) there are a lot of indexes
> with no value so it's constantly jumping between 0 and the correct value. Is
> there a way to get pd to approximate the values in between (more or less an
> average between plotted points)?
>
> Thanks so far for all the help
> Tyler
>
>
> On Fri, Apr 8, 2011 at 11:12 PM, Mathieu Bouchard <matju at artengine.ca>wrote:
>
>> On Fri, 8 Apr 2011, Tyler Leavitt wrote:
>>
>>  I am trying to graph a section of a circle into an array. I have been
>>> trying to wrap my head around [sin] and [cos] but none of my configurations
>>> get results. If you had a circle with radius 100 with a center at (0, 0) I'm
>>> trying to get the upper right quadrant (positive x and positive y). The
>>> start point being (100,0) and the end point being (0,100).
>>>
>>> Any ideas on moving forward?
>>>
>>
>> use angles between 0 and pi/2 = 1.5708
>>
>> putting those into [cos] and [sin] will give you values for a circle of
>> radius 1 at (0,0). For different radiuses you apply [*] after that.
>>
>> quadrants and clockwiseness depend on which axis uses [cos], which axis
>> uses [sin], and which direction of each axis is positive. There are several
>> standards for those things.
>>
>>  _______________________________________________________________________
>> | Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC
>>
>
>
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